CALIFORNIA STATE UNIVERSITY, NORTHRIDGE

Stratigraphy and Detrital Zircon U-Pb Geochronology of the El Paso Mountains

Permian Metasedimentary Sequence, Southern California

A thesis submitted in partial fulfillment of the requirements

For the degree of Master of Science in Geology

By

Eric Kenneth McDonald

December 2016 The thesis of Eric Kenneth McDonald is approved:

______Dr. Kathleen Marsaglia Date

______Dr. Richard Heermance Date

______Dr. Mary Robinson Cecil, Chair Date

California State University, Northridge

ii

Acknowledgments

I would like to thank my thesis committee: Drs. Mary Robinson Cecil, Kathleen

Marsaglia, and Richard Heermance. I am grateful to have been provided with this interesting and exciting project, their time in the laboratory and the field, and for the many long and stimulating discussions regarding a land- and seascape that existed over

250 million years ago.

I am grateful for the support from Marilyn Hanna, the National Science

Foundation, and the Department of Geological Sciences at California State University,

Northridge.

I would like to thank Theresa Dunn and Mari Flores-Garcia in the main office of the Department of Geological Sciences. Their administrative expertise, kind advice, and chocolate candy helped me get through graduate school.

Jean Rains, a previous graduate student, laid much of the foundation for this work. It was wonderful to meet on the department’s “Fall Field Frolic” geology excursions and to discuss these rocks with her, the only other person who knows them as well as I do.

I would also like to thank Dr. Nancy Riggs and Stephen Dobbs from Northern

Arizona University for our collaboration and discussions of the larger context of my research. I was lucky enough to travel with Stephen to Caborca, Mexico to do fieldwork on the southern counterpart to the rocks discussed in this thesis. It was an unforgettable experience. Nancy Riggs also collected, processed, and analyzed two of my detrital

iii zircon samples (DZ-5 and DZ-6) before I arrived at California State University,

Northridge.

Many of my fellow students joined me in the El Paso Mountains and gave their varied perspectives on the geological structures, lithologies, and stratigraphy of my study area. The Spring 2015 Stratigraphy class, including Hannah Cohen, Nathan Dickey,

Samantha Gebauer, Kyle Johnson, Jeffery Joseph III, and Vincent Zhao, measured some of the strata with me. These rocks are not easy to study and interpret, and I truly appreciate your time and attention.

Four of my fellow students, Brittany Huerta, Jeffery Joseph III, Jennifer

Rittenburg, and Vincent Zhao, took time out of their own schedules to camp and do fieldwork with me. In particular, Jeffery Joseph III spent a week alone with me in the

Mojave desert, patiently enduring my sometimes bossy and eccentric tendencies while providing vital support and motivation. Thanks again.

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Dedication

To the memory of Elliott “Jack” McDonald Jr.

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Table of Contents

Signature Page ii Acknowledgments iii Dedication v Abstract vii

Introduction 1 Geologic Background 4 Tectonic Setting 4 Geology of the El Paso Mountains 8 Previous Work on the Holland Camp strata 11 Methods 13 Mapping and Stratigraphy 13 Conglomerate Clast Counts 14 Petrography and Sandstone Point Counts 14 Detrital Zircon U-Pb Geochronology 15 Results 17 Structure and Alteration 17 Stratigraphy Overview 18 Holland Camp Unit 1 (Ph1) 19 Holland Camp Unit 2 (Ph2) 20 Holland Camp Unit 3 (Ph3) 22 Holland Camp Unit 4 (Ph4) 23 Goler Gulch Andesite (Pgg) 24 Conglomerate Clast Counts and Petrography of Various Rock Types 24 Detrital Zircon U-Pb Geochronology Results 27 Discussion 31 Detrital Zircon Maximum Depositional Ages 31 Depositional Environment Interpretations and Basin Architecture 33 Sedimentary Petrology and Provenance 38 Detrital Zircon Provenance 42 Tectonic and Paleogeographic Reconstruction 48 Conclusions 56

References 58

Appendix A: Table Captions and Tables 72 Appendix B: Figure Captions and Figures 80 Appendix C: Plate Captions and Plates 110 Appendix D: LA-ICP-MS Data for All Concordant Detrital Zircon Grains 115

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Abstract

Stratigraphy and Detrital Zircon U-Pb Geochronology of the El Paso Mountains

Permian Metasedimentary Sequence, Southern California

By

Eric Kenneth McDonald

Master of Science in Geology

Permian metasedimentary strata in the central El Paso Mountains, southern

California, were deposited contemporaneously with the inception of subduction and the development of a volcanic arc along southwestern Laurentia, and may be one of the only records of this major transition in Californian tectonics. It is debated whether they were deposited offshore to the west, or entrained in a late Paleozoic sinistral transform system that displaced crustal blocks from the northwest prior to east-west contraction by subduction zone tectonics. In this study, new stratigraphy, sedimentary provenance, and

U-Pb detrital zircon data elucidate the paleogeography of this tectonically active continental margin, and contribute to broader reconstructions of the North American

Cordillera.

Over 2500 m of Permian strata in three stratigraphic sections were divided into five informal units: Ph1-Ph4 and Pgg, from oldest to youngest. Ph1 consists of argillite, conglomerate and conglomeratic and sandy limestone rich in recycled chert clasts, interpreted as a submarine fan deposits. Ph2 consists primarily of conglomerate and

vii litharenite lenses derived from recycled marine sedimentary rocks, interpreted as channelized submarine canyon, and fan and/or base-of-slope deposits. Ph3 consists of silty, normally-graded carbonate beds and fossiliferous limestone, interpreted as a turbidite sequence deposited above the carbonate compensation depth. Ph4 consists of feldsarenite, volcaniclastic arenite and volcanic-bearing conglomerate, carbonate beds, and argillite, interpreted as continental shelf deposits. Ph4 is capped by and interbedded with Pgg andesitic lavas. Conglomerate clast counts and sandstone point counts show an up-section diversification of detritus entering the basin, from primarily recycled chert in

Ph1 to a mixture of recycled sedimentary and volcanic lithic clasts in Ph4 deposits.

Detrital zircon data from six sandstone horizons indicate that the Permian strata of the El Paso Mountains were deposited from ca. 280-255 Ma. Detrital zircon populations, which are interpreted to derive from three sources, show changing provenance up- section. Ph2 sedimentary litharenites yielded primarily ca. 330-280 Ma zircons derived from a Panthalassan island arc system and Precambrian grains recycled from Paleozoic sedimentary rocks of the Cordilleran passive margin. In contrast, Ph4 feldsarenites yielded primarily ca. 277-255 Ma zircons, interpreted to derive from a nascent continental arc along southwestern Laurentia. The disappearance of Precambrian grains in Ph4 sandstones was likely due to subsidence of their source(s) and/or the construction of a topographical barrier along the new continental arc axis. The results of this study support the hypothesis that this sequence is composed of allochthonous marine sedimentary rocks and lavas with equivocal transport history, recording a shift from transform to subduction zone tectonics along southwestern Laurentia from middle to late

Permian time.

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Introduction

The process of subduction initiation is a fundamental component of plate tectonic theory, but it is poorly understood because there are very few modern incipient subduction zones and only scarce examples of subduction initiation within the rock record (e.g. Collot et al., 1995; Gurnis et al., 2004; Stern, 2004; Marsaglia, 2012). Thus, the stratigraphic record and paleogeographic response to subduction initiation and volcanic arc development are not well-studied. However, late Permian stratigraphic sequences and related igneous rocks in the southwestern United States and northwestern

Mexico have been suggested to record the initiation of subduction along the southwestern margin of Laurentia (Walker, 1988; Martin and Walker, 1995; Carr et al., 1997; Rains et al., 2012). Identifying and studying these deposits is important for evaluating models for continental truncation and subduction initiation, as well as understanding the paleogeographic response to this tectonic event.

The southwestern margin of Laurentia underwent major tectonic changes during the Paleozoic Era. From Neoproterozoic to middle Paleozoic time, southwestern

Laurentia was characterized by a northeast-striking passive margin sequence which developed over Mojave, Yavapai, and Mazatzal continental basement provinces

(Hoffman, 1989; Dickinson, 2000; Gehrels and Pecha, 2014). This margin is thought to have been truncated in Pennsylvanian time by sinistral faulting along the cryptic, north- striking California-Coahuila transform system (Walker, 1988; Dickinson and Lawton,

2001). The California-Coahuila transform system is inferred to extend from the eastern

Sierra Nevada range in central California, along the San Andreas fault in southern

1

California, and run northeast of the Gulf of California in Sonora, Mexico (Figure 1;

Dickinson and Lawton, 2001; Chapman et al., 2015). It is generally thought that subduction initiated during the Permian along the California-Coahuila transform system, ultimately resulting in the development of a continental arc that crosscut older depositional and structural trends (Hamilton and Myers, 1966; Burchfiel and Davis, 1972,

1975). However, the geologic record of subduction initiation has largely been obscured by subsequent episodes of arc magmatism and deformation; there are few exposures of

Permian strata along the Mojave segment of the continental margin, and of these few, only those of the El Paso Mountains include volcaniclastic and volcanic deposits (e.g.

Carr et al., 1984, 1997).

Permian strata exposed in the El Paso Mountains (herein termed the Holland

Camp strata) comprise a sequence of low-grade metamorphosed carbonate and siliciclastic marine sedimentary rocks that have been interpreted to represent an early, arc-related basin-fill remnant (Rains et al., 2012). Deepening and shallowing trends were interpreted to reflect changes in base level in response to vertical tectonics predicted by models of subduction initiation (Hall et al., 2003; Gurnis et al., 2004; Rains et al., 2012).

These strata grade upward into volcaniclastic rocks and are capped by the Permian Goler

Gulch andesite (Martin and Walker, 1995; Carr et al., 1997) suggesting the basin was adjacent to a newly-forming volcanic arc at that time.

This study expands on previous work in the central El Paso Mountains by Rains et al. (2012) by measuring and describing two additional stratigraphic sections and doing additional clast counts, sedimentary petrography, and detrital zircon analysis. New results from this study help to constrain the depositional timing and paleogeography of the El

2

Paso Mountains Permian metasedimentary strata within the context of an evolving continental margin. Stratigraphic and petrologic study of the Holland Camp strata reveals an overall shallowing trend within a marine depositional environment and an up-section diversification in the character of detritus entering the basin, ultimately including the products of a coeval volcanic source. Detrital zircon U-Pb geochronology results suggest that deposition began in late Cisuralian to Guadalupian time (ca. 280-260 Ma) in close proximity to a deactivated Carboniferous to early Permian (ca. 330-280 Ma) offshore arc system, prior to the emergence of a Lopingian (260-252 Ma) volcanic center along southwestern Laurentia. These findings argue for southward translation of the Permian

Holland Camp basin and a shift from borderland-style to arc-related sedimentation as subduction initiated along the truncated continental margin.

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Geologic Background

Tectonic Setting

From Neoproterozoic to middle Paleozoic time, a thick, northeast-trending, passive margin sequence was deposited along the western (Cordilleran) margin of

Laurentia (Burchfiel and Davis, 1972, 1975; Davis et al., 1978; Dickinson, 2000, 2004;

Cocks and Torsvik, 2011). This passive margin sequence is comprised of continental shelf, slope, rise, and abyssal plain facies belts (e.g. Chapman et al., 2012, 2015) which were fragmented and reorganized primarily by late Paleozoic transform and compressional tectonics (Dickinson and Lawton, 2001; Stevens et al., 2005). Continental shelf strata are exposed in the White-Inyo Mountains, Death Valley, Mojave desert, and

Caborca block (Figure 1; Stewart et al., 1984, 2005; Dickinson, 2000; Stevens et al.,

2005). Fragments of the continental slope are preserved as wall-rock pendants within the

Sierra Nevada batholith (Figure 1; Stevens and Greene, 1999). Continental rise and abyssal plain deposits are exposed in the Roberts Mountains allochthon and the El Paso terrane (Figure 1; Schweickert and Lahren, 1987; Dunne and Suczek, 1991; Dunne and

Saleeby, 1993; Carr et al., 1997). The abyssal plain facies belt consists of the Foothills ophiolite and overlying hemipelagic sedimentary rocks (Saleeby, 1992, 2011).

Cordilleran passive margin sedimentation was partially disrupted by thrusting of the Roberts Mountains allochthon onto the continental shelf during the Late Devonian to

Mississippian Antler orogeny (Nilsen and Stewart, 1980; Speed and Sleep, 1982). From latest Devonian to Permian time, sediment was eroded from the uplifted Roberts

4

Mountains allochthon and shed eastward into the Antler foreland basin and locally into the Antler overlap assemblage (Johnson and Pendergast, 1981; Speed and Sleep, 1982;

Dickinson, 2000).

The El Paso terrane consists of Cambrian to Carboniferous metasedimentary rocks of the Kern plateau and northern Mojave region, including those of the El Paso

Mountains (Dunne and Suczek, 1991; Dunne and Saleeby, 1993; Stevens et al., 2005;

Chapman et al., 2012, 2015). These metasedimentary packages are coeval with and lithologically similar to rocks of the Roberts Mountains allochthon, Antler foreland basin, and Antler overlap assemblage (Poole, 1974; Carr et al., 1981, 1984, 1997). Two models have been proposed to explain how the El Paso terrane relates to the Antler orogenic belt and shelf facies rocks in the White-Inyo Mountains, Death Valley, and Mojave desert

(Figure 1). The first argues that the El Paso terrane represents a thin and sinuous segment of the passive margin in southern California that was thrust onto the craton, in the hanging wall of the Last Chance thrust during the Permian (Poole and Sandberg, 1977;

Dickinson, 1977; Snow, 1992; Stevens and Stone, 2005a). The second, which has become favored by recent workers, argues that the El Paso terrane was translated southward from the latitude of the Roberts Mountains allochthon from Pennsylvanian to

Permian time along the California-Coahuila transform system (Davis et al., 1978;

Burchfiel and Davis, 1981; Stewart et al., 1984, 1990; Stevens and Stone, 1988; Stone and Stevens, 1988; Dickinson and Lawton, 2001; Stevens et al., 1992, 2005; Saleeby,

2011; Saleeby and Dunne, 2015; Chapman et al., 2015). Evidence cited for this displacement includes the Caborca block of northern Mexico. Temporally and lithologically correlative shelf facies rocks exposed in the Caborca block and in Death

5

Valley and the White-Inyo Mountains of eastern California appear offset along a cryptic discontinuity sub-parallel to the San Andreas fault (Stewart et al., 1984, 2005; Dickinson and Lawton, 2001).

The initiation of subduction along southwestern Laurentia is indicated by a discontinuous belt of Permian to Triassic (ca. 275-207 Ma) arc-related plutons, extending from the El Paso terrane to the Caborca block along the trace of the California-Coahuila transform (Figure 1; Miller et al., 1995; Barth et al., 1997; Dickinson and Lawton, 2001;

Barth and Wooden, 2006; Arvizu et al., 2009; Cecil et al., 2016; Ferrer et al., 2016).

Saleeby (2011) posited that subduction of aged Panthalassan lithosphere initiated at ca.

255 Ma, based on a Sm/Nd garnet-matrix age for high-pressure metamorphism and suturing of the Foothills ophiolite against Sierran framework crust. However, this age is younger than some arc-related plutons in the El Paso terrane (Cecil et al., 2016; Ferrer et al., 2016), suggesting that high-pressure metamorphism of the ophiolite sampled by

Saleeby (2011) may have postdated the initiation of subduction and related arc magmatism in the area. The Foothills suture (Figure 1) is considered the boundary between Panthalassan lithosphere and transitional or continental crust, and therefore may be the closest approximation of the cryptic subduction megathrust (Saleeby, 1992, 2011).

There are few preserved sedimentary successions that may have recorded events along the California-Coahuila transform during active translation and subsequent subduction initiation. Permian deposits of the northwestern Mojave region have been described as sediments of borderland affinity, deposited in rapidly subsiding fault- controlled basins (Stone and Stevens, 1984, 1988; Stevens and Stone, 1988; Walker,

1988). The Permian Holland Camp strata of the El Paso Mountains (Figure 1, 2) contain

6 the earliest known record of a volcanic arc in the Mojave region (Burchfiel and Davis,

1981; Burchfiel et al., 1993; Martin and Walker, 1995; Carr et al., 1997; Rains et al.,

2012). To the south, the Middle Permian to Jurassic El Antimonio Group of the Sierra del

Alamo in Sonora, Mexico (Figure 1) may be an early remnant of the continental forearc

(González-León, 1997). Detrital zircons from a Permian horizon yielded a ca. 271 Ma peak (Riggs et al., 2009, 2010), and volcanic clasts have been documented in a Triassic conglomeratic horizon (Riggs et al., 2015), suggesting that these deposits were at least receiving detritus from a nearby Permian to Triassic volcanic arc.

A series of Panthalassan intraoceanic arcs, including the Yreka-Trinity, Northern

Sierra, and Eastern Klamath terranes of California, and the Quesnellia and Yukon-Tanana terranes of British Columbia, Yukon, and Alaska were positioned outboard from the

Cordilleran passive margin and were active throughout Paleozoic time (e.g. Davis et al.,

1978; Miller et al., 1992; Dickinson, 2000, 2004; Blakey, 2007; Cocks and Torsvik,

2011; Domeier and Torsvik, 2014). Ediacaran to Devonian intrusions and ophiolites are found in the Yreka-Trinity terrane (Wallin et al., 1988; Rubin et al., 1990). The Eastern

Klamath and Northern Sierra terranes include volcanic, volcaniclastic, and sedimentary rocks of early Devonian to early Mississippian age (Lapierre et al., 1985; Lapierre et al.,

1987; Miller and Cui, 1989; Rouer and Lapierre, 1989; Rubin et al., 1990; Metcalf et al.,

1998) and late Mississippian to Permian age (Watkins, 1985, 1990; Lapierre et al., 1987;

Miller, 1987). Farther north, the Quesnellia and Yukon-Tanana terranes include

Devonian to Permian intrusive, volcanic, volcaniclastic and sedimentary rocks (Nelson and Friedman, 2004; Baranek, 2006; Nelson et al., 2006).

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Paleozoic island arcs outboard of the western margin of Laurentia are collectively referred to as the McCloud arc system (Figure 1), due to their late Paleozoic amalgamation and subsequent regional onlap of the Permian McCloud Limestone (Ross and Ross, 1983; Miller, 1987; Blakey, 2007; Colpron et al., 2007; Saleeby, 2011; Cocks and Torsvik, 2011; Saleeby and Dunne, 2015). The McCloud arc system accreted onto the Laurentian margin during the Triassic Sonoma orogeny, which thrust Late Devonian to Permian continental rise and abyssal plain deposits of the Golconda allochthon onto the Roberts Mountains allochthon (Figure 1; Burchfiel and Davis, 1972, 1975; Speed,

1979; Chapman et al., 2012, 2015). The McCloud arc system became part of the overriding plate of a Mesozoic continental subduction zone after the Sonoma orogeny

(Dickinson, 2000, 2004; Saleeby and Dunne, 2015).

Geology of the El Paso Mountains

The El Paso Mountains are located approximately 140 km north-northeast of Los

Angeles in Kern County, California (Figure 1). This small range is approximately 30 km across and reaches a maximum elevation of 1,559 m. The northern boundary is gently sloping, whereas the southern boundary steep and structurally controlled by the Garlock fault (Figure 2). The range is composed of a diverse assemblage of Cambrian to Permian metasedimentary and metavolcanic rocks and Permian to Jurassic plutons (Figure 2;

Dibblee, 1952; 1967). Paleogene nonmarine to marine deposits of the Goler Formation onlap the basement along the northern margin (Figure 2; Cox, 1987). The bedrock is incised by generally south-southeast-directed streams that ultimately coalesce in alluvial fans at the edge of Fremont Valley (Figure 2). Quaternary alluvial terraces, covering much of the bedrock and lining the streambeds, contain gravel apparently derived from

8 the igneous and metasedimentary rocks that outcrop throughout the range. Quaternary colluvial deposits are locally present at the bases of steep, rocky slopes (Carr et al.,

1997).

The Garlock assemblage, formerly known as the “Mesquite Schist and Garlock

Formation” (Dibblee, 1952, 1967), includes all Paleozoic metasedimentary and metavolcanic rocks of the El Paso Mountains (Carr et al., 1984; 1997). The late Cambrian to Devonian marine units (metasedimentary rocks of El Paso Peaks, Colorado Camp,

Gerbracht Camp, and others) may correlate with the Roberts Mountains allochthon to the north (Poole et al., 1980). Similarly, Carboniferous marine units, including the metasedimentary rocks of Apache Mine (herein termed the Apache Mine strata) and the

Pennsylvanian metasedimentary rocks of Benson Well (herein termed the Benson Well strata), have been loosely correlated with deposits of the Antler foreland basin and overlap assemblage adjacent to the Roberts Mountains allochthon (Poole, 1974; Carr et al., 1981, 1984, 1997).

The El Paso Mountains have two separate Permian sequences: 1) the Holland

Camp and the overlying Goler Gulch andesite in the central part of the range (Figure 2), and 2) the Bond Buyer sequence on the western edge of the range (Martin and Walker,

1995; Carr et al., 1997). These units differ from age-equivalent strata of the Antler overlap assemblage and Golconda allochthon in that they include metamorphosed arc- type andesites. The Goler Gulch andesite yielded a zircon U-Pb concordia lower intercept age of 262 ± 2.3 Ma, whereas the meta-andesite in the Bond Buyer sequence yielded an upper intercept age of 281 ± 8 Ma (Martin and Walker, 1995). These meta-andesites,

9 together with their interbedded metasedimentary rocks, may be remnants of a Permian forearc basin (e.g. Rains et al., 2012).

Units of the Garlock assemblage are juxtaposed by a combination of steeply- dipping depositional contacts, southwest-verging reverse faults, and east-northeast- trending strike-slip faults. The density of strike-slip faults increases with proximity to the

Garlock Fault to the south (Figure 2; Carr et al., 1997). Inclined tight to isoclinal folds with north-northwest-trending axes occur at both regional and outcrop scales, and penetrative and spaced cleavages appear to have developed in conjunction with contractional deformation throughout the range, possibly in late Permian time

(Christiansen, 1961). The Garlock assemblage is composed of the least-metamorphosed

Paleozoic sedimentary rocks in the El Paso terrane (Carr et al., 1981; Dunne and Suczek,

1991). However, authigenic quartz, albite, muscovite, and chlorite are nearly ubiquitous, indicating that regional metamorphism up to greenschist facies has altered the entire assemblage (Christiansen, 1961).

An igneous suite in the western El Paso Mountains is composed of variably deformed Permian and Triassic plutons. Foliated plutons, including the Weiss Mountain gneiss, are exposed adjacent to metasedimentary rocks just west of Mesquite Canyon

(Figure 2; Carr et al., 1997). Ductile deformation and regional metamorphism of the

Garlock assemblage appear to have occurred in conjunction with Late Permian pluton emplacement (Christiansen, 1961). Other Permian and Triassic plutons, including the

Burro Schmidt and Last Chance Canyon plutons (Figure 2), are undeformed and post- date any ductile deformation and regional metamorphism within the El Paso Mountains

(Christiansen, 1961). The Jurassic Laurel Mountain pluton, on the eastern end of the El

10

Paso Mountains, intruded the Garlock assemblage on the eastern end of the range (Figure

2; Carr et al., 1997). Sr, Nd, and Pb isotopic signatures indicate that the Late Permian

Last Chance Canyon pluton ascended through oceanic crust, whereas the Jurassic Laurel

Mountain pluton ascended through the Laurentian craton. It is inferred from their U-Pb zircon ages and isotopic signatures that bedrock units of the El Paso Mountains, with possibly those of the entire El Paso terrane, constitute a klippe that was emplaced eastward approximately 100 km onto the Laurentian craton by ca. 175 Ma (Miller et al.,

1995).

Previous Work on the Holland Camp strata

The Permian Holland Camp strata and the Goler Gulch andesite are the youngest units of the Garlock assemblage, deformed into a broad, westward-verging syncline in the central El Paso Mountains (Figure 2). Early biostratigraphic work determined a Permian age for these rocks based on the identification of Schwagerina spp. fusulinids (Dibblee,

1952; Ross and Sabins, 1966). The thickest and most intact sections are exposed in the western limb of the syncline. Carr et al. (1981, 1984, 1997) divided these strata into three units, Pha, Phb, and Phc, based on Permian biostratigraphic markers. Pha and Phb have late Wolfcampian to Leonardian (ca. 280-270 Ma) fusulinids and conodonts; Phc contains latest Leonardian (ca. 270) conodonts near the base.

Rains (2009) conducted a stratigraphic and petrologic study of most stratigraphically-intact section of Holland Camp strata just south of Mormon Flat in the central El Paso Mountains (Figure 2). In this section, the Holland Camp strata were assumed to rest unconformably on Cambrian through Ordovician metasedimentary rocks

11 immediately to the west (Carr et al., 1997; Rains et al., 2012), although the contact was not described in detail by these workers. To the south, the Holland Camp strata are faulted over Mississippian strata (Carr et al., 1997). Based on geodynamic models for subduction initiation along a prior transform fault (Hall et al., 2003; Gurnis et al., 2004),

Rains et al. (2012) interpreted these strata as early forearc deposits that reflect tectonic uplift and subsidence on the overriding plate, involving 1) subaerial uplift

(conglomerate), 2) rapid subsidence below the carbonate compensation depth (fine- grained deposits), 3) gradual shallowing (bioclastic carbonates) and 4) the influx of arc- derived detritus (volcaniclastic strata) from a nearby volcanic arc. Sandstone detrital modes indicate a change in provenance from recycled orogenic sources to a volcanic arc source over time, culminating in the onset of andesitic volcanism (Rains et al., 2012).

Two other stratigraphic sections and smaller, isolated outcrops of the Holland Camp strata have required further stratigraphic investigations and detrital zircon geochronology to understand the cryptic depositional and paleogeographic context of these rocks.

12

Methods

Mapping and Stratigraphy

The broader chronostratigraphic units (i.e. the metasedimentary rocks of Apache

Mine, Benson Well, Colorado Camp, and Holland Camp, and the Goler Gulch andesite and Goler Formation) were mapped according to the lithologies provided by Carr et al.

(1997), subunits of the Holland Camp strata were redefined in this study. The units were mapped at a 1:10,000 scale, with five meter topographic contours constructed in ArcMap.

Global Positioning System (GPS) waypoints were taken with a hand-held Garmin eTrex

GPS unit using the North American Datum of 1983. Bedding plane and foliation attitudes were measured with a Brunton compass, and the thicknesses of bedding planes were measured at a resolution of 0.5 m using a Jacob staff and measuring tape. Three stratigraphic sections exposed in the central El Paso Mountains form the foundation for this study, each separated by approximately 1 km along strike. Section 1, just south of

Mormon Flat (Figures 2, 3), was measured originally by Rains (2009). Using the stratigraphic measurements from Rains (2009) as a framework, the covered intervals in her column were filled-in with lithologies exposed within approximately 5 m along strike. The other two sections were chosen for their continuous exposures along hilltops and ridgelines. Section 2 extends sub-parallel to EP 11, on the north side of the road

(Figure 3). Section 3 is on the south side of EP 11, north of Iron Canyon (Figure 3).

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Conglomerate Clast Counts

Conglomerate clast counts were conducted in the field at the five distinct gravel- bearing horizons within the Holland Camp strata. At each clast count location, a net with

3 cm spacing was draped over the gravel-bearing outcrop, and the intersections within the net were marked on the rock face. The net was then lifted and marked clasts, medium pebble-sized and larger (>1 cm), were counted within an enclosed area. 100 clasts were counted at each location, excluding all matrix points. Clast lithologies were verified by petrographic analyses.

Petrography and Sandstone Point Counts

Due to significant post-depositional alteration, petrographic observations were necessary to make protolith interpretations for many lithofacies. Standard, 30 μm thick, uncovered petrographic thin sections were made the 28 samples with grain sizes larger than medium silt (>16 μm). These consist primarily of samples of the Holland Camp strata (n = 23), but also include samples from the nearby Apache Mine strata (n = 3),

Benson Well strata (n = 2), and Goler Gulch andesite (n = 1). Feldspar-bearing slides were stained using a technique developed by Marsaglia and Tazaki (1992), which stains calcic minerals pink and potassic minerals yellow. The intensity of the color reflects the concentration of calcium and potassium; feldspars, zeolites, lithic fragments and other components were highlighted in this way. All slides were finished with standard glass coverslips. Table 2 lists petrographic descriptions.

For petrographic analysis, the various components of these rocks were described in terms of their abundance, shape, grain size, and alteration. Components included

14 monomineralic grains, lithic fragments, bioclasts, and authigenic phases. Rock textures, alteration, and matrix characteristics were also described.

Detrital framework grains in sandstones provide valuable information about the tectonic setting and provenance of sedimentary basins. Eleven thin sections from sandstone horizons were point counted for modal analysis using the Gazzi-Dickinson method (Dickinson et al., 1983; Dickinson, 1985). Sandstone components were counted with an evenly-spaced, two-dimensional grid. For each sample, 300 points were counted, including matrix (n = 18-92; Table 3). The influence of grain size on modal composition was minimized by counting sand-sized (0.06–2.00 mm) mineral grains within lithic clasts as monomineralic grains (Ingersoll et al., 1984). Points within the groundmass of lithic clasts were counted as lithic clasts instead of matrix. Sandstone lithofacies were named according to the classification scheme of Folk et al. (1970).

Detrital Zircon U-Pb Geochronology

Six sandstone horizons within the Holland Camp strata were selected for detrital zircon geochronology. For each sample, 15 to 30 kilograms were collected from quartzose or volcaniclastic horizons with minimal evidence of intrusions or hydrothermal alteration. Zircons were extracted using standard rock crushing and mineral separation techniques at California State University, Northridge. Whole rock samples were disaggregated with a Sturtevant 2x6” jaw crusher, followed by a Bico UA type pulverizer and ceramic mortar and pestle until all grains would pass through a 355 micron stainless steel mesh. High-density minerals were then concentrated with a Wilfley 13A shaker table and manually-operated plastic gold pan. Magnetite was removed with a hand-held

15 gold magnet. The remaining magnetic grains were separated in steps of increasing amperage (0.5, 0.8, and 1.3 amperes) using a S. G. Frantz L-1 isodynamic magnetic separator set at a 15° horizontal angle and a 20° vertical angle. Secondary density separation was completed with the heavy liquid methylene iodide (CH2I2) (density = 3.31 g/mL). The remaining zircon-rich mineral separates were poured onto double-sided tape to be mounted in epoxy. Chips of zircon standards (91500, Plesovice, Temora-2, and

CSUN PEIXE) were added. After curing for approximately 24 hours, the epoxy mounts were sanded to expose the grain cores and polished down to a 3 μm grit.

Cathodoluminescence (CL) and back scatter electron (BSE) images were taken with a

FEI Quanta 600 W-filament electron scanning microscope (SEM) in order to identify contaminant non-zircons as well as fractures and metamict zones in zircon grains.

Detrital zircon samples are numbered in ascending stratigraphic order (Table 5;

Figure 8). Samples for DZ-1, DZ-2, DZ-3, and DZ-4 were analyzed with a Thermo

Finnigan ELEMENT2 magnetic sector LA-ICP-MS coupled to a New Wave Research

193 nm ArF excimer laser at California State University, Northridge. Ablated spots were

35 μm in diameter. Samples DZ-5 and DZ-6 were analyzed with a Nu Instruments

Plasma HR multi-collector LA-ICP-MS coupled to a Photon Machines 193 nm ArF excimer laser at the University of California, Santa Barbara, using a 25 μm diameter spot.

Sample sizes range from 28 to 160 grains. Analyses of detrital zircons were bracketed by, and corrected for, using the zircon standard 91500 (Wiedenbeck et al., 1995). Data reduction was performed using the Iolite package in WaveMetrics IgorPro.

16

Results

Structure and Alteration

The Holland Camp strata have a foliation coplanar to original bedding (e.g. Plate

1D). Many lithofacies exhibit fissile cleavage and tectonically-flattened pebbles. Zeolite facies metamorphism is indicated by abundant, authigenic clay minerals, zeolites, micas, and quartz and calcite overgrowths (Utada, 2001a, 2001b), which were observed in thin sections. Plagioclase and volcanic lithic fragments have been partially replaced by authigenic clay and/or zeolite minerals. Bedding plane and bedding plane foliations strike north-northwest and dip east-northeast with attitudes ranging from 48° to 89°, generally steepening from east to west (Figure 3, 4; Plate 1A). Some faulted blocks appear vertical or slightly overturned (Figure 3). All pre-Mesozoic lithologies may be described with the prefix “meta”, which has been omitted in the following sections for clarity.

There are three tectonostratigraphic units of Paleozoic rocks in the study area, each separated by a moderately-dipping (30-60°) dip-slip fault: the Permian Holland

Camp strata to the east, the Cambrian to Ordovician Colorado Camp strata in the center, and the Carboniferous Apache Mine and Benson Well strata to the west (Figures 3, 4).

Contrary to the work of Carr et al. (1997) and Rains et al. (2012), which assumed a local depositional contact between the Permian strata and underlying units, no such disconformity could be identified in the vicinity of Section 1. Basal Holland Camp strata

(Ph1) are in the hanging wall of a predominantly dip-slip fault, marked by a 2-3 m thick fault gouge locally hosting hydrothermal minerals (e.g. malachite and chalcanthite, south of Holland Camp), where no bedrock could be reached by shallow excavation (Plate 1B).

17

Holland Camp, Colorado Camp, and Apache Mine – Benson Well strata are all exposed near Mormon Flat, whereas to the south, Holland Camp strata are faulted against Apache

Mine strata, thereby covering the units in between (Figures 3, 4). A faulted block of basal

Holland Camp strata that was previously mapped as Apache Mine strata by Carr et al.

(1997) was identified beneath similar Holland Camp lithofacies west of Iron Canyon

(Figure 3).

The fault separating Holland Camp strata from underlying Paleozoic units has been mapped as an east-dipping thrust fault by Carr et al. (1997; Figure 2). This fault post-dates deposition of the Permian Holland Camp strata, but pre-dates deposition of the

Paleocene Goler Formation, thus making it likely Mesozoic in age. The fault plane is sub- parallel to bedding all along the fault trace (Figures 3, 4), and there are outcrop-scale (<2 m) folds near the base of Section 3. Juxtaposition of Permian rocks in the hanging wall against Cambrian to Mississippian rocks in the footwall suggests that this is a normal fault, but its history may be more complex, possibly involving 1) normal slip, and 2) reactivation and reversal of slip. As reported by Rains et al. (2012), no definitive evidence for slip sense have been published or observed.

Stratigraphy Overview

Four units of the Holland Camp strata were identified based on lithofacies associations: Ph1, Ph2, Ph3, and Ph4, in ascending stratigraphic order. Each of the three stratigraphic sections contains all four units (Figures 3, 5-8). Section 1 is 947 m thick

(Rains et al., 2012), with a 306 m thick covered interval straddling the Ph1-Ph2 boundary

(Figure 5). Section 2 is 831 m thick, with only small-scale fault offsets (Figure 6).

18

Section 3 is 679 m thick, with multiple fault offsets and a structurally truncated base

(Figure 7). Coarse-grained lithofacies form outcrops up to 6 m tall, commonly along high ridges, whereas fine-grained lithofacies, which are more susceptible to erosion, underlie saddles and valleys. Sparse outcrops in areas largely covered by Quaternary deposits are fine-grained (i.e. argillite and siltstone). Most beds are laterally discontinuous over distances of 10-30 m and are locally offset 0.5-3 m by small lateral faults.

All three sections were correlated with the base of Ph3 and Ph3-Ph4 fossiliferous limestone marker beds (Figure 8), and the stratigraphic heights of beds in Sections 2 and

3 were based on those of Section 1 (Rains et al., 2012). In comparison to the Holland

Camp units from Carr et al. (1997), Pha has been divided into Ph1 and Ph2, Ph3 is roughly equivalent to Phb, and Ph4 is roughly equivalent to Phc (Figure 17), and the contacts between units have been redefined in some parts of the study area, such as the base of Ph4 in Section 3 (Phc of Carr et al., 1997), and the fault near the top of Section 2

(Figure 3).

Holland Camp Unit 1 (Ph1)

Ph1 consists of chert-clast conglomerate, rare cherty litharenite, and lenses of sandy limestone with conglomeratic bases encased in argillite. The base of Unit Ph1 is defined by chert-clast conglomerate and/or sandy limestone overlying a 2-3 m-wide fault zone. Sand to cobble-sized clasts are predominantly sub-angular, blackened chert

(Figures 9, 10). The unit thickness of Ph1 in Section 1 is 134 m, where the upper contact is covered by Quaternary alluvium. Ph1 thickness ranges from 234 m in Section 2 to 170 m in Section 3 (Figures 5-8).

19

The argillite is light gray, fissile, silty, and largely devoid of primary sedimentary structures and bioturbation. Conglomeratic lenses, up to 4 cm thick with sharp-bases, are sparsely distributed within the argillite. The lowermost argillite beds are slightly calcareous, with carbonate content decreasing up-section. Nereites sp. ichnofossils and

Permian fusulinids have been reported in this lithofacies (Carr et al., 1984).

The conglomerate forms massive, mildly foliated, clast-supported beds with a maximum grain size of 30 cm, in 1-14 m thick packages with gradational upper contacts

(<1 m) beneath similar cherty litharenite and argillite. The conglomerate and sandstone are most abundant in the base of Section 1 and extend approximately 2 km to the north along strike (Figure 3). To the south, these beds appear to have been largely faulted out of the bases of Sections 2 and 3 (Figures 3, 8).

The sandy limestone beds are uneven and up to 4 m thick, forming packages up to

30 m thick, and extending 2-50 m along strike. Locally, these lenses graded upward from

1-3 cm thick, gravel-bearing bases over less than 1 m thick intervals. The coloration is medium gray, weathering to a light brown with an elephant skin outer surface. Quartz commonly fills fractures within the limestone.

Holland Camp Unit 2 (Ph2)

Ph2 consists of argillite, conglomerate lenses, litharenite, and sparse sandy limestone. The base of Unit Ph2, as observed in Sections 2 and 3, is defined by the appearance of litharenite bearing a variety of sedimentary clast types. Conglomerate and litharenite, abundant in Sections 2 and 3, occur as sparse lenses in Section 1, but were observed in Ph2 outcrops nearest to Mormon Flat, north of where Section 1 was

20 measured (Figure 3). The unit thickness of Ph2 is 40 m in Section 1, where the lower contact is covered by Cenozoic deposits. Ph2 thickness ranges from 256 m in Section 2 to

188 m in Section 3 (Figures 5-8).

The argillite is light gray, fissile, silty, non-calcareous, and increases in abundance up-section in Sections 2 and 3. In Section 1, the area covered by Quaternary alluvium and the Paleocene Goler Formation to the southwest of Mormon Flat is likely underlain by argillite, which is relatively nonresistant to erosion. Small, rare outcrops of argillite were observed along EP 11 in this area (Figure 3). Coarser-grained lithofacies pinch out along the northern and southern edges of this covered area (Figure 8). Sparse sandy limestone form tabular beds up to 30 cm thick in the upper portion (above approximately 370 m).

The conglomerate beds are massive and foliated, with sedimentary clasts-sizes up to 0.3 m throughout Ph2 (Figures 9, 10; Plate 1C). Sparse boulder-sized (up to 1.1 m) limestone clasts were observed at a horizon approximately 420 m above the base in

Section 2. The conglomerate are primarily matrix-supported, but some clast-supported beds are also present; the matrix is dominated by silt and sand-sized grains. Lenses have a minimum thickness of 10 cm, with amalgamated bodies of lenses reaching a maximum thickness of approximately 50 m in Section 2. The bases of conglomerate beds are sharp, but they locally grade upward into litharenite over intervals of 0.5-2 m. The isolated Ph2 outcrops to the north of Section 1 and to the west of Mormon Flat are primarily conglomerate.

The litharenite is foliated and occurs as both sheets and lenses, with 2-8 cm thick bedding. The coarser sandstone beds are generally massive, but locally exhibit normal

21 and reverse grading and poorly-defined “relict” cross-laminae, likely obscured by metamorphism. Finer-grained, more quartzose litharenites, appearing at approximately

400 m, have relict parallel laminae and 2-3 cm wide burrows. Lenses within the top 10 m of Ph2 in Section 2 contain sand-sized bioclasts.

Holland Camp Unit 3 (Ph3)

Ph3 consists primarily of calc-siltstone, calc-argillite, and fossiliferous limestone.

In Section 1, there are some lenses of feldsarenite and calcarenite, starting at approximately 570 m. The base of Unit Ph3 is defined by a shift from argillite to calc- argillite and calc-siltstone. The unit thickness of Ph3 is 162 m in Section 1, 182 m in

Section 2, and 143 m in Section 3.

The calc-siltstone beds, up to 30 cm thick, are normally graded with 30-100 cm argillite partings (Plate 1D). The calc-argillite is light gray, weathering to reddish brown, fissile, and silty. They form low-lying outcrops that make-up over 90% of measured strata throughout Ph3.

The fossiliferous limestones are medium gray, matrix-supported and slightly sandy, with iron nodules and crinoid macrofossils. They form massive, 1-6 m thick tabular beds, 1-2 m tall outcrops, and are relatively resistant to erosion. Permian conodonts have been reported in this lithofacies (Carr et al., 1984).

Ph3 sandstone lithofacies are confined to Section 1. The feldsarenite forms lenses that are 1-3 m thick, with fine to medium-grained plagioclase feldspar. There is an approximately 10 m thick interval of calcarenite at 640 m (Rains et al., 2012).

22

Holland Camp Unit 4 (Ph4)

Ph4 consists of volcaniclastic arenite and volcanic-bearing conglomerate, feldsarenite, calcarenite, argillite, calc-siltstone, and fossiliferous limestone. The base of

Unit Ph4 is defined by the shift from a sequence dominated by calc-siltstone and calc- argillite to a sequence with abundant feldsarenite and volcaniclastic arenite. The Ph3 unit thickness is 295 m in Section 1, 159 m in Section 2, and 177 m in Section 3.

The argillite, calc-siltstone, and fossiliferous limestone lithologies are similar to those of Ph3, so much that they appear to be younger equivalents of those lithofacies.

Permian conodonts have been reported in these lithofacies (Carr et al., 1984).

Feldsarenite and calcarenite beds are fine to coarse-grained, light brown to gray, and exhibit relict cross-laminae. They are more abundant, relative to volcaniclastic arenite, in the lower part of the unit. Rains et al. (2012) observed fine-grained quartz arenite in the lower part of the unit in Section 1, interbedded with volcaniclastic arenite.

The volcaniclastic arenite and volcanic-bearing conglomerate are olive-gray, foliated, and form sheet-like beds up to 10 m thick. The volcaniclastic arenite is fissile, grayish-green, slightly calcareous, and devoid of primary sedimentary structures. The conglomerate, limited to Sections 2 and 3, is massive, matrix-supported, with clasts reaching a maximum size of 0.25 m. The composition includes sedimentary, aphanitic volcanic, and porphyritic andesitic fragments (Figures 9, 10) in a slightly calcareous and sandy matrix.

23

Goler Gulch Andesite (Pgg)

Pgg consists of light olive gray to very light blue andesite, forming low-lying, nonresistant outcrops (Plate 1E). The texture is aphanitic to porphyritic, with phenocrysts of plagioclase up to 3 mm long and amphibole up to 2 mm long, locally exhibiting a mild tectonic foliation. Phenocrysts are preferentially weathered and commonly replaced by authigenic clay minerals (Plate 4D). Pgg andesitic flows are interfingered with Ph4 sedimentary beds in Sections 1 and 3 (Figures 3, 5, 7, 8). Small, porphyritic andesite dikes and/or sills, similar to Pgg lava flows, were found intruding Holland Camp strata throughout the study area.

Conglomerate Clast Counts and Petrography of Various Rock Types

Conglomerate clast count results are presented in Table 1 and Figures 9 and 10.

Figure 10 shows an upward diversification of clast types, from predominantly chert clasts in Ph1, to a mixture of sedimentary and volcanic clasts in Ph4. All thin section observations, including those of conglomerate clasts, are presented in Table 2. Modal estimates in Table 2 were based on five levels of abundance: predominant (>50%), abundant (30-50%), common (5-30%), minor (1-5%), and trace (<1%). In thin sections, all lithic clasts appear to be of the same metamorphic grade as the surrounding rock, indicating that they were undeformed rock fragments at the time of deposition.

All thin section observations are presented in Table 2. Modal estimates in Table 2 were based on five levels of abundance: predominant (>50%), abundant (30-50%), common (5-30%), minor (1-5%), and trace (<1%). Sandstone point count results are presented in Table 3. As with the conglomerate clasts, all detrital framework grains

24 appear to be of the same metamorphic grade as the surrounding rock. Figure 10 shows how sandstone framework grains change up-section.

Thin sections from the units underlying units of the Holland Camp strata include two litharenite samples (EM15-40, EM15-43) and one bedded chert sample (EM15-03) from the Mississippian Apache Mine strata, and a chert siltstone (EM15-15) and chert- clast conglomerate (EM15-14) from the Pennsylvanian Benson Well strata (Figure 3;

Carr et al., 1997). Silt and sand-sized detrital grains in Apache Mine and Benson Well lithofacies include predominant chert, minor to abundant monocrystalline quartz, siltstone, argillite, and sandstone fragments, and traces of biotite, iron oxides, and carbonate in matrix of chlorite and mica (Table 2).

Clast count 1 (CC-1) was conducted on a Ph1 conglomerate (EM15-16) at 30 m in

Section 1 (Figures 5, 8). The conglomerate is clast-supported with sub-angular, blackened pebbles and cobbles of chert (99%) and siltstone and argillite (1%).

Thin sections from Ph1 include one chert-clast conglomerate, one sandy limestone, and two limestone samples. Detrital grains in Ph1 lithofacies are predominantly sub-angular, with trace to minor amounts of argillite, siltstone and quartz

(Figures 9, 10; Plates 2A, 2B) in silty, calcite-rich matrix. As noted by Rains et al.

(2012), chert fragments include radiolarian and spicular varieties (Table 2).

Clast counts 2, 3, and 4 (CC-2, CC-3, and CC-4) were conducted on Ph2 conglomerates in Section 2 (Figures 6, 8). Conglomerate CC-2 (EM15-23), at 247 m, is matrix-supported, with sub-angular to sub-rounded pebbles and cobbles of chert (38%), siltstone and argillite (32%), and quartz arenite (30%). Conglomerate CC-3 (EM15-25), at 318 m, is clast-supported with sub-angular to sub-rounded pebbles and cobbles of chert

25

(58%), siltstone and argillite (33%), and quartz arenite (9%). Conglomerate CC-3

(EM15-29), at 419 m is matrix-supported with sub-angular to sub-rounded pebbles and cobbles of chert (56%), siltstone and argillite (28%), quartz arenite (11%), and limestone

(5%).

Thin sections from Ph2 include five litharenite, two quartzose litharenite, one bioclast-bearing litharenite, and three conglomerate samples. Silt and sand-sized detrital grains in Ph2 conglomerate and litharenite lithofacies are abundant chert, and lesser amounts of argillite, siltstone, quartz arenite, limestone, and traces of volcanic fragments, as well as abundant monocrystalline quartz, common plagioclase, calcite, iron oxides, and traces of zircon (Plate 3B), titanite, and tourmaline in a matrix rich in zeolite and/or clay minerals, chlorite, and mica (Figures 9, 10; Plates 2C, 2D, 3A, 3C). Litharenite lenses within the top 10 m of Ph2 in Section 2 (Figure 6) contain significant amounts of bioclasts, including crinoid and other echinods, rugose coral, sponge spicule, and possible bryozoan and foraminifer remains (Table 2).

Thin sections from Ph3 include one sandy fossiliferous limestone and two fossiliferous limestone samples. Ph3 limestone lithofacies are predominantly carbonate with common silt and sand-sized particles of chert, argillite, siltstone, monocrystalline quartz, iron oxides, and traces of plagioclase, quartz arenite, and microlitic volcanic fragments (Figure 10; Plate 3D). Bioclastic fragments include common crinoids, and trace to minor bryozoans, fusulinids, and possible other foraminifera, and fusulinid.

Detrital fragments and bioclasts are separated by a silty, carbonate matrix (Table 2).

Clast count 5 (CC-5) was conducted on a Ph4 volcanic-bearing conglomerate

(EM15-39) at 753 m in Section 2 (Figures 6, 8). The conglomerate is matrix-supported

26 with sub-angular to sub-rounded pebbles and cobbles of limestone (38%), chert (14%), aphanitic volcanic fragments (13%), feldsarenite (12%), siltstone and argillite (9%), and porphyritic andesite (4%).

Thin sections from Ph4 include one volcaniclastic arenite, and one volcanic- bearing conglomerate, one feldsarenite, and two calcareous feldsarenite samples. Silt and sand-sized grains in Ph4 sandstones and conglomerates include common to predominant plagioclase and carbonate clasts, and minor to common monocrystalline and polycrystalline quartz, iron oxides, chert, limestone, argillite, siltstone, feldsarenite, porphyritic andesite, volcanic fragments with both lathwork and microlitic textures, and traces of zircon and garnet in a matrix rich in zeolite and/or clay minerals, chlorite, and mica (Figures 9, 10; Plates 4A-4C). Bioclasts include crinoids and other echinoid fragments, and sponge spicules (Table 2).

Detrital Zircon U-Pb Geochronology Results

A total of six zircon-bearing horizons were sampled in Ph2 and Ph4. Detrital zircons are much more common quartz-rich sedimentary rocks (e.g. Fedo et al., 2003).

Therefore, no samples were taken from Ph1 or Ph3 rocks because they are relatively devoid of monocrystalline quartz. One fine-grained quartz arenite from approximately

680 m above the base in Section 1 was processed, but zircon extraction was unsuccessful for this sample. Detrital sample locations are given in Table 5, and all U-Pb age data are given in Appendix D. Probability distribution plots for the six detrital zircon spectra are shown in Figures 11-16. Ages younger than 1.0 Ga are 206Pb*/238U ages; those older than

1.0 Ga are 207Pb*/206Pb* ages. Zircon ages were deemed concordant and suitable for

27 provenance analysis if they exhibited less than 30% discordance, owing to Pb loss, and

10% reverse discordance, due to excess radiogenic Pb accumulation, Pb redistribution between different zones of the crystal structure, and/or analytical error (Mattinson et al.,

1996; Kusiak et al., 2013).

The most prominent age peaks in all spectra are Permian, including early

Cisuralian (ca. 298-282 Ma) age peaks in Ph2 spectra, and Guadalupian (ca. 267-264 Ma) age peaks in Ph4 spectra. Ph2 spectra contain lesser age peaks at ca. 1.0 Ga, 1.8 Ga, and

2.6 Ga, whereas Precambrian grains are largely absent from Ph4 strata.

Sample DZ-1 (Figure 11) is from a Ph2 granule-bearing litharenite (EM15-42), collected at 239 m in Section 2 (Figure 6). Zircons are predominantly 200-400 µm, sub- angular grains with minor 100-200 µm sub-rounded to rounded grains. Of 154 analyzed grains, 113 were concordant. Peak ages were observed at ca. 460 Ma and 298 Ma. The population consists predominantly of 363-330 Ma ages (85.0%), with diffuse age ranges between 1.93-1.74 Ga, 475-444 Ma and single grain ages at 2.43 Ga, 2.21 Ga, 1.46 Ga,

702 Ma, 612 Ma, and 511 Ma. Only 11% of all grains analyzed yielded Precambrian ages. The maximum depositional age of this sample is taken to be 283.3 ± 5.4 Ma, based on the YC2σ(19) age. Maximum depositional age calculations and interpretations are included in the subsequent discussion section of this thesis and listed in Table 5.

Sample DZ-2 (Figure 12) is from a Ph2 coarse-grained litharenite (EM15-04), collected at 294 m in Section 2 (Figure 6). Zircons are 100-200 µm and sub-angular to sub-rounded. Of 119 analyzed grains, 113 were concordant. A single peak age was observed at ca. 296 Ma. All ages fall into a 323-268 Ma population. The maximum

28 depositional age of this sample is taken to be 281.2 ± 4.6 Ma, based on the YC2σ(19) age.

Sample DZ-3 (Figure 13) is from a Ph2 fine-grained quartzose litharenite (EM15-

28), collected at 394 m in Section 2 (Figure 6). Zircons are a mixture of 100-200 µm, sub-angular grains and 30-100 µm, sub-rounded to rounded grains. Of 161 analyzed grains, 151 were concordant. Peak ages were observed at ca. 2.60 Ma, 1.80 Ga, 990 Ma, and 282 Ma. The population primarily consists of a 387-256 Ma sub-group (47.0%), with 1.98-1.63 Ga, 1,099-921 Ma, 488-435 Ma age sub-groups, and more diffuse ages from 2.75-2.50 Ga, 1.57-1.13 Ga, and 834-529 Ma, and single ages at 2.29 Ga and 2.23

Ga. Of all grains analyzed, 49% yield Precambrian ages. The maximum depositional age of this sample is taken to be 264.3 ± 7.6 Ma, based on the YC2σ(10) age.

Sample DZ-4 (Figure 14) is from a Ph2 granule-bearing litharenite lens with abundant bioclasts (EM15-41), collected at 468 m in Section 2 (Figure 6). Zircons are a mixture of 100-400 µm, sub-angular grains and 30-100 µm, sub-rounded to rounded grains. Of 156 analyzed grains, 110 were concordant. Peak ages were observed at ca 1.80

Ga and 290 Ma. The population consists primarily of 338-256 Ma ages (58.2%), with diffuse age ranges between 2.71-2.49 Ga, 2.08-1.67 Ga, and 1,090-405 Ma, and single ages at 2.83 Ga, 2.29 Ga, and 2.19 Ga. Of all grains analyzed, 38% yielded Precambrian ages. The maximum depositional age of this sample is taken to be 263.0 ± 10 Ma, based on the YC2σ(4) age.

Sample DZ-5 (Figure 15) is from a Ph4 granule-bearing volcaniclastic arenite

(EP-2), collected at 665 m in Section 1 (Figure 5). Of 47 analyzed grains, 44 were concordant. A single peak age was observed at ca. 264 Ma. The population consists

29 predominantly of 277-237 Ma ages (95.5%), with two Precambrian ages at 2.11 Ga and

1.83 Ga (4.5). The maximum depositional age of this sample is taken to be 258.0 ± 1.5

Ma, based on the YC2σ(13) age.

Sample DZ-6 (Figure 16) is from a Ph4 medium-grained feldsarenite (EP-5,

EM15-38), collected at 682 m in Section 2 (Figure 6). Of 122 analyzed grains, 121 were concordant. A single peak age was observed at ca. 267 Ma. The vast majority of zircons fall into a tight sub-group of 291-251 Ma ages, with a single age at 333 Ma. The maximum depositional age of this sample is taken to be 255.5 ± 2.3 Ma, based on the

YC2σ(7) age.

30

Discussion

Detrital Zircon Maximum Depositional Ages

For maximum depositional age calculations, only grains exhibiting less than 10% discordance and 5% reverse discordance were used. Maximum depositional ages were calculated in three ways based on the youngest clusters of ages; Tuffzirc(n), YC1σ(n), and YC2σ(n), all incorporating 1σ errors, where n equals the number of grains within the cluster. TuffZirc(n) (zircon age extractor algorithm in Isoplot) is a Monte Carlo analysis which takes the median age of the youngest coherent cluster of ages, excluding those with anomalously high errors (Ludwig and Mundil, 2002). YC2σ(n) is the weighted mean of the youngest cluster of three or more ages overlapping at 2σ, whereas YC1σ(n) is the weighted mean of the youngest cluster of two or more ages overlapping at 1σ (Dickinson and Gehrels, 2009a). TuffZirc(n), YC2σ(n), and YC1σ(n) maximum depositional age calculations are in decreasing order of sample size and conservativeness (e.g. Dickinson and Gehrels, 2009a). Each method produced younging-upward trends, with few outliers

(Table 5). All maximum depositional ages are presented with a 95% confidence interval

(1.96σ), and are listed in Table 5.

TuffZirc(n) was the most conservative method with the largest samples sizes, and provides a highly reliable estimate of the absolute maximum depositional age, while providing the loosest constraint on the true depositional age of each sample. DZ-1, at 239 m, was deposited at 293.1 +3.0 -5.0 Ma at the very earliest. TuffZirc(n) maximum depositional ages are similar to the peak ages for all samples. YC1σ(n), with its smaller sample sizes, is the least conservative method for determining maximum depositional

31 age, with the largest margins of error. With the exception of DZ-1, all YC1σ(n) ages overlap in error with YC2σ ages.

YC2σ(n) used much smaller sample sizes than TuffZirc(n), but produced the clearest younging-upward trend of all three methods, and is viewed as the most reliable method in this study. Based on YC2σ ages, Ph2 to lower Ph4 strata have max depo ages between 283.3 ± 5.4 Ma and 255.5 ± 2.3 Ma (Table 5; Figure 17).

It is important to consider the time difference, or “lag time”, between zircon crystallization and deposition. The source rock(s) and overlying materials must undergo sufficient denudation to release zircons so that they may be subsequently transported and deposited in a basin. For example, the estimated lag time for detrital zircons in deep marine forearc strata of the Cretaceous Great Valley Group are 8-17 Myr (DeGraaff-

Surpless et al., 2002). In contrast, most of the estimated lag times for detrital zircons in marine strata of the Olympic Structural Complex, deposited alongside the active, early

Miocene Cascadia volcanic arc, were less than 3 Myr (Stewart and Brandon, 2004). As a general rule, orogenic sources can have lag times of 5-10 Myr or longer, whereas volcanic sources have lag times of less than 5 Myr (Carter and Bristow, 2000). Therefore, the minimum lag time for detrital zircons in Ph2 deep marine strata is estimated to be 5

Myr. The maximum lag time for detrital zircons in Ph4 arc-derived strata is estimated to be 3 Myr. These numbers are only estimates, based on comparisons between data presented herein on the Holland Camp strata and published data for other deposits.

The inferred depositional ages of Holland Camp strata are based primarily on the

YC2σ(n) calculated ages and estimated lag times (Figure 17). Global chronostratigraphic units are used in this study (Cohen et al., 2012; Gradstein et al., 2012). Ph1 is probably of

32 late Cisuralian age, based on the ca. 280 Ma biostratigraphic date of Carr et al., (1984).

Ph2 is likely late Cisuralian to earliest Lopingian (ca. 273-260 Ma) in age. Upper Ph2

YC2σ(n) ages have wide margins of error (Table 5), which calls into question the younger age bracket for this unit. A late Guadalupian to early Lopingian age is inferred for Ph3. YC2σ(n) and YC1σ(n) ages both indicate a Lopingian age (ca. 255 Ma) for the strata near the base of Ph4. These maximum depositional ages are markedly slightly younger than the ca. 280-270 Ma biostratigraphic ages from Carr et al. (1981, 1984,

1997), which may have been based on transported fossils with lag times of their own.

The Permian Goler Gulch andesite (Pgg), which is interfingered with Ph4 strata at the tops of Sections 2 and 3 (Figures 5, 7-8), is taken to be 262 ± 2.3 Ma, based on a zircon U-Pb multi-grain TIMS lower intercept age from Martin and Walker (1995).

However, this sample was collected in Goler Gulch (Figure 2) where it cannot be reliably correlated with the Pgg flows in Iron Canyon. Due to the apparent time-transgressive nature of Pgg across Sections 1, 2, and 3 (Figure 8) and the uncertain stratigraphic relationship between Pgg flows in Iron Canyon and in Goler Gulch, this datum does not serve as a reliable minimum depositional age for the Holland Camp strata in the study area. In summary, the Holland Camp strata are inferred to have accumulated from ca.

280-252 Ma (late Cisuralian to Lopingian; Figure 17), and may have extended into the

Early Triassic Period (<252 Ma).

Depositional Environment Interpretations and Basin Architecture

Ph1 lithofacies are characteristic of marine slope and rise deposits (e.g. Reading and Richards, 1994; Stow and Mayall, 2000; Payros et al., 2008; Arnott, 2010). A deep

33 marine setting was determined by Carr et al. (1984), based on the presence of Nereites sp. ichnofossils in fine-grained beds near the base. Slightly calcareous mudstone and siltstone, indurated to argillite, are interpreted as hemipelagic background sedimentation

(Stow and Piper, 1984; Stow and Tabrez, 1998). The basal chert-clast conglomerate, with its minor rounding, poor sorting, massive bedding, and coarse (up to cobble) clast sizes indicate a high-energy transport mechanism. A submarine fan setting at the base of a relatively steep continental slope is probable, but a broader slope apron cannot be ruled out because the original bedding geometry and extent have been obscured by faulting and limited exposure (e.g. Reading and Richards, 1994). Small gravel-bearing lenses and larger sandy limestone lenses with are interpreted as turbiditic(?) channel-fill and lobe deposits of variable width (2-50 m) and thickness (0.1-4 m thick lenses in 1-30 m thick packages). Locally, these lithofacies exhibit normal grading from small scale (<1 m) gravelly bases, but not the characteristic ripples and laminae of idealized turbidite sequences (Bouma, 1962), which may have been obscured by post-depositional alteration. Small (<1 m) gravel wedges within some lenses may be lateral accretion surfaces, reflecting minor channel migration and sinuosity (e.g. Braga et al., 2001; Jobe et al., 2010). Potential analogs include the calciclastic submarine fan complex of the Eocene

Anotz Formation in the western Pyrenees (Payros et al., 2007), and calciclastic submarine lobes and channels of the Vera Basin in southern Spain (Braga et al., 2001). Carbonate content and the abundance of channel-fill deposits and coarse grained lithofacies decreases up-section, indicating subsidence near or below the carbonate compensation depth (Bickert, 2009; Rains et al., 2012) and an overall decrease clastic sediment supply.

34

Ph2 strata are characteristic of channelized marine slope and/or base of slope deposits (e.g. Reading and Richards, 1994; Galloway, 1998; Stow and Mayall, 2000).

The lateral facies changes between Sections 1 and 2 and other isolated outcrops are interpreted as channel boundaries (Figure 8). However, no definitive levee-type facies or buttress unconformities were identified. The argillite lithofacies, including what likely underlies the covered interval in Section 1, represents siltstone and mudstone background sedimentation (Stow and Piper, 1984; Stow and Tabrez, 1998) in the space between channels that are up to 50 m deep. The overlapping lenses of matrix-supported conglomerate and litharenite are interpreted as amalgamated debris flows and high- density turbidites confined to channels that cut into the argillite (e.g. Shanmugam and

Moiola, 1988; Galloway, 1998; Stow and Mayall, 2000). It is inferred that argillite beds between the channels are older than channel-fill deposits. Comparable settings include the channelized deep marine deposits of the Oligocene-Miocene Numidian Flysch of

Sicily and Tunisia (Johansson et al., 1998; Sami et al., 2010), and the deep marine, coarse-grained channel-fill deposits of the Cretaceous Cerro Toro Formation in southern

Chile (Romans et al., 2011; Bernhardt et al., 2011). The conglomerate clasts are more rounded in Ph2 than in Ph1, reflecting greater transport distances from their source(s).

Tabular argillite beds separating beds of sandstone and conglomerate are interpreted as mudstone drapes, deposited during cessations in clastic supply (e.g. Galloway, 1998).

The upper portion of the Ph2 unit reflects a slight change in the depositional environment. Burrowed quartzose litharenites at approximately 400 m (Section 2; Figure

6) represent a transition to a low-energy environment, fed by more quartz-rich and bioclastic sources, possibly from shallow marine regions along the continental margin.

35

Channel incision and infilling with conglomerate occurred on a much smaller scale, with maximum channel thickness of 14 m. Rare sandy limestone beds, which constitute less than 1% of the measured Ph2 strata, are interpreted as turbidites with carbonate detritus transported from regions above the carbonate compensation depth (e.g. Payros et al.,

2008; Arnott, 2010).

Ph3 strata may have been deposited in a deep marine environment (e.g. Reading and Richards, Shanmugam and Moiola, 1988; Stow and Mayall, 2000; Playton et al.,

2010). In accordance with the work of Carr et al. (1984, 1997), calc-argillite and normally-graded calc-siltstone are interpreted as hemipelagic mudstones and fine-grained turbidites deposited above the carbonate compensation depth (Stow and Piper, 1984;

Stow and Tabrez, 1998; Bickert, 2009). In contrast to Ph1 carbonate turbidites, Ph3 turbidites are more laterally continuous, more fine-grained, and form broad sheets. The calc-siltstone turbidites lack the ripples characteristic of idealized turbidite sequences

(Bouma, 1962), which, as with Ph1 strata, may have been obscured by post-depositional alteration. Bedded fossiliferous limestones contain crinoid, bryozoan, and fusulinid fragments that were likely transported from shallower regions along the continental margin. Sparse sandstone lenses may represent shallowly-incised channels or lobes

(Reading and Richards, 1994; Arnott, 2010).

Ph4 lithofacies are characteristic of a continental shelf environment adjacent to an active volcanic arc (e.g. Mount, 1984; Cant and Hein, 1986; Soja, 1996; Wilson and

Lokier, 2002). Sandstone sheets are interbedded with argillite and minor calc-siltstone and fossiliferous limestone, representing similar environment conditions to those of Ph3, but with higher energy event beds. The contact between Ph3 to Ph4 is marked by

36 distinctive influx of volcaniclastic material, and the shift to a sand-dominated system.

Carbonate and fine-grained sediment accumulation occurred between surges of volcaniclastic detritus (e.g. Wilson and Lokier, 2002). Ph4 sandstones have previously been identified as turbidites (Carr et al., 1984, 1997), but they lack sedimentary structures to support this interpretation (Bouma, 1962; Reading and Richards, 1994). Relict cross- laminae in the feldsarenite beds are possible indicators of shallowing above the storm- weather wave base or shallower (e.g. Cheel and Leckie, 1993). The higher proportion of andesitic clasts and volcaniclastic material implies that volcanic eruptions played an important role in sediment supply onto the shelf. The volcaniclastic material in sandstone lithofacies was largely reworked from primary volcanic deposits.

Pgg andesites are interpreted as continental arc lavas (Gill, 1981; Stern, 2002).

Pgg lavas and Ph4 beds are interfingered near the base of Pgg; Ph4 deposition was coeval with volcanic activity from a nearby arc. Pgg lavas are time-transgressive (Figure 8), and may have been at first confined to channels or topographic lows before covering all strata within the basin. Andesitic volcanism appears to be cogenetic with the dikes and/or sills of andesitic magma found throughout the sequence, based on the similarities in lithology.

The Holland Camp strata were wholly deposited in a marine basin in the vicinity of a developing volcanic arc, as was determined previously by Carr et al. (1984, 1997).

Because outcrops of the Holland Camp strata are limited to less than 10 km2 of poorly exposed, highly-tilted beds in the central El Paso Mountains, the overall size and shape of the basin is not possible to ascertain with certainty. Each unit represents a significant change in the depositional environment, with an overall shallowing trend. In accordance with Rains et al. (2012), the stratigraphic sequences reveal a history of uplift (Ph1

37 conglomerate), subsidence and deep-water sedimentation (Ph1), and then gradual shallowing into a shelfal environment (upper Ph2 to Ph4). However, lateral variations in

Ph2 strata indicate a period of channelized erosion and siliciclastic sedimentation prior to shallowing into the Ph3-Ph4 shelfal environment. Global sea-level curves indicate stable to mildly fluctuating ocean depths during the Permian (Haq and Schutter, 2008), suggesting that tectonic uplift and subsidence, rather than eustatic fluctuations, were the primary factors controlling up-section lithofacies changes (Rains et al., 2012).

Sedimentary Petrology and Provenance

The clast and grain types in siliciclastic deposits provide insight into the character of their sediment sources. Conglomerate clast types may indicate what rock types were subaerially exposed in the drainage basin, and sandstone detrital modes may be quantitatively examined to infer the tectonic setting at the time of deposition (e.g.

Dickinson et al., 1983). Sandstone point count and conglomerate clast count horizons are shown on the stratigraphic columns in Figures 5-8. Figure 10 shows how sandstone and conglomerate clast types evolved throughout the basin history.

Framework parameters from Ph2 litharenites and Ph4 feldsarenites were recalculated and plotted on four different ternary diagrams, superimposed over data points from Rains (2009). Recalculated parameters are listed in Table 4. QmFLt and

QtFL diagrams, after Dickinson et al. (1983), aid in differentiating between sub- categories of continental block, recycled orogen, and magmatic arc provenances by comparing the relative abundances of quartz, feldspar, and lithic fragments (Figures 10B,

10C, 18A). QpLvLs diagrams are used to characterize convergent margin sources by

38 comparing the relative abundances of different lithic fragments (Figure 18C; Dickinson et al., 1985). QmKP diagrams may be useful in determining whether sandstones were derived from intraoceanic arcs, continental arcs, or other settings (Figure 18D; Marsaglia and Ingersoll, 1992). Unfortunately, flow directions are equivocal due to the scarcity of preserved paleocurrent indicators.

All Ph1 sandstone and conglomerate strata, including CC-1, contain predominantly chert fragments, with argillite and siltstone fragments and rounded monocrystalline quartz in minor to trace amounts (Tables 1, 2; Figures 5, 9, 10). The high angularity of clasts and grains throughout Ph1 suggests that they were transported only a short distance. Although no sandstone point counts were conducted on any Ph1 strata, the inferred source(s) of framework grains were subaerially uplifted marine, chert-rich sedimentary rocks, as seen in other subduction complex or fold-thrust belt tectonic settings (Dickinson et al., 1983; Pettijohn et al., 1987).

Ph2 strata include PC-1 to PC-8 and CC-2, CC-3, and CC-4 (Tables 1-3; Figures

5-10). Framework clasts and grains are predominantly recycled lithic fragments, especially chert, but with higher proportions of siltstone, argillite, quartz arenite, and limestone fragments than in Ph1. The base of Ph2 marks the first appearance of minor amounts of feldspar and traces of volcanic lithic fragments. One sample (PC-6) contains a variety of invertebrate fossil fragments (EM15-41; Table 2). The abundance of carbonate increases up-section (Figure 10).

The QmFLt diagram shows Ph2 sandstones plotting primarily on the lithic end of the recycled orogen fields, with one sample (PC-2) within the undissected arc field

(Figure 18A). Ph2 sandstones plot within the craton interior and recycled orogen fields on

39 the QtFL diagram (Figure 18B). However, the matrices of these samples may be composed of silt and fine sand-sized lithic fragments affected by compaction, diagenesis, and metamorphism (Pettijohn et al., 1987), thus diminishing the recycled lithic component and shifting them in composition into the craton interior field. Ph2 sandstones plot in the chert-rich corner of the mixed orogen field on the QpLvLsm diagram (Figure

18C), and the non-arc-related field on the QmKP diagram (Figure 18D).

Ph2 detrital fragments were derived primarily from uplifted marine sedimentary rocks which may have been part of a subduction complex or fold-and-thrust belt orogen

(Dickinson et al., 1983; Pettijohn; 1987). The upward diversification of lithic clasts in

Ph1 and Ph2 strata may be due to unroofing of a sequence of marine sedimentary rocks capped by prominent, chert-rich units, or expansion from a highly localized drainage basin underlain by chert-rich rocks for Ph1 deposits, to more broadly distributed catchments characterized by a variety of exposed sedimentary rocks for Ph2 deposits.

Minor feldspar and volcanic lithic fragments were derived from a volcanic arc, recycled arc-related sediments, or an older rifting event. Pebble to boulder-sized lithic clasts indicate that the source(s) were at least in part subaerially exposed.

Some Ph2 litharenite beds and Ph3 limestone beds contain common bioclastic fragments, including crinoid, bryozoan, brachiopod, and rugose coral fossils, and minor monocrystalline quartz and chert and siltstone lithic fragments (Table 2). Much of the detrital carbonate material in these units may be recrystallized bioclasts or limestone lithic fragments. The bioclastic fragments were likely transported from shallow water ecosystems. The Carboniferous to Permian Bird Spring and Keeler Canyon Formations of eastern California and western Nevada are potential sources for these fragments (Yose

40 and Heller, 1989; Stevens and Stone, 2007; Rains et al., 2012). Another potential source is the Permian McCloud Limestone of northern California, which also contains bryozoans, corals, and echinoderms, but the “Tethyan” coral macrofossils, characteristic of the McCloud faunal assemblage (Watkins, 1985; Miller and Wright, 1987), were not observed in the Holland Camp strata.

Ph4 strata include PC-9 to PC-11 and CC-5 (Tables 1-3; Figures 5, 6, 8, 9). Ph4 sandstones are composed of varying amounts of feldspar, monocrystalline quartz, and variable amounts of volcanic and sedimentary lithic framework grains. Plagioclase, rather than potassium feldspar, makes up 100% of the feldspar content. Ph4 lithic fragments include chert, siltstone, argillite, and limestone clasts, similar to Ph2 strata, but with feldsarenite, aphanitic volcanic lithic fragments, porphyritic andesite, and volcanic glass fragments as well. Within a stratigraphic interval of approximately 20 m, volcaniclastic arenite (PC-9), and feldsarenite (PC-10, PC-11) were deposited, reflecting similar, but possibly distinct sources. More feldspathic lithofacies may have been derived from slightly older and more distant volcanic sources than volcaniclastic lithofacies. As Ph4 deposition continued, the total abundances of monocrystalline feldspar and quartz decreased as the abundances of volcanic and volcaniclastic fragments increased.

The QmFLt and QtFL diagrams show that Ph4 plagioclase-rich sandstones, sampled from the lower part of the member (below approximately 700 m), plot within the basement uplift fields (Figure 18A-B), with one sample (PC-11) plotting in the QmFLt transitional arc field (Figure 18A). Although this suggests that exposed continental basement rocks were recycled into these strata, Ph4 detrital zircon samples (DZ-5 and

DZ-6) yielded very few grains of the corresponding Archean and Proterozoic ages (e.g.

41

Gehrels and Pecha, 2014). Furthermore, the high plagioclase content would require compositionally immature plutonic sources, such as gabbro, diorite, and/or anorthosite.

Locally, volcanic lithic fragments are only partially replaced by authigenic clay. As noted by Rains (2009), the total lithic content may have been diminished during diagenesis and metamorphism due to devitrification and/or zeolite replacement of volcanic lithic fragments (Pettijohn et al., 1987; Utada, 2001a, 2001b), shifting the data points from arc- related to basement uplift fields. All three Ph4 sandstones analyzed in this study plot within the QpLvLsm mixed orogen field (Figure 18C) and near or within the QmKP arc- related fields (Figure 18D). Rains (2009) analyzed several volcaniclastic arenite beds, which are more prominent in the upper part of Ph4 (above approximately 700 m). They plot primarily within the undissected arc and transitional arc fields of the QmFLt and

QtFL diagrams (Figure 18A-B), and largely within the arc orogen and intraoceanic arc fields of the QpLvLsm and QmKP diagrams, respectively (Figure 18C-D; Rains, 2009;

Rains et al., 2012). In summary, Ph4 framework grains and lithic fragments were primarily derived from volcanic arc and uplifted marine, carbonate-rich sedimentary rock sources (Figure 10). Marine sedimentary lithic fragments may have been recycled from an orogen associated with subduction tectonics.

Detrital Zircon Provenance

Figures 19 and 20 are a normalized probability density plots for all six Holland

Camp detrital zircon samples. Each sample yielded predominantly Paleozoic grains, yet provenance is inferred to change markedly between deposition of Ph2 and Ph4 (no

42 zircon-bearing horizons were found in units Ph1 and Ph3). The potential sources are discussed in the following section.

Ph2 litharenites are dominated by Carboniferous to early Permian zircons, and contain less than 50% Precambrian grains (Figures 19, 20). This suggests limited derivation from the Laurentian interior. In comparison, temporally-correlative strata in the Colorado plateau (Hermit Formation, Coconino Sandstone, Toroweap Formation, and

Kaibab Limestone) similarly contain Carboniferous to early Permian zircons, which were interpreted to have been derived from Appalachian orogenic belts, but also contain abundant Precambrian grains, suggesting that these sediments were deposited in an autochthonous basin with unobstructed access to the Laurentian interior (Gehrels et al.,

2011). Considering the contrast in provenance between the Ph2 strata and Permian rocks further inland, Ph2 detrital-zircon spectra indicate accumulation with partially obstructed access to the Laurentian craton, with ca. 380-270 Ma zircons derived from an offshore source.

One such possible source is the McCloud arc system, consisting of Paleozoic intraoceanic arcs and arc-flank sedimentary rocks that collided with western Laurentia by

Early Triassic time (e.g. Miller et al., 1992; Dickinson, 2000; Saleeby, 2011; Saleeby and

Dunne, 2015). Fragments of the McCloud arc system are exposed today in the Yreka-

Trinity, Northern Sierra, Eastern Klamath, Quesnellia, and Yukon-Tanana terranes

(Nelson and Friedman, 2004; Nelson et al., 2006; Colpron et al., 2007; Cocks and

Torsvik, 2011; Saleeby and Dunne, 2015).

Ph2 zircon ages (ca. 380-270 Ma, where most fall within the 330-280 Ma range with 298-282 Ma age peaks) are enigmatic in that they are a poor match with published

43 pluton radiometric dates in the western United States and southwestern Canada (e.g.

Dickinson, 2004). These zircons may have originated in a nearby segment of the

McCloud arc system, or they may have been carried from north to south by strong longshore or contour currents (e.g. Gehrels et al., 1995) from the vicinity of the

Quesnellia and Yukon-Tanana terranes (Nelson and Friedman, 2004; Baranek; 2006;

Nelson et al., 2006). Pennsylvanian to early Permian volcanic and volcaniclastic strata of the Baird Formation (Eastern Klamath terrane) indicate that volcanism was occurring at this time along the southern end of the arc system (Watkins, 1985, 1990; Lapierre et al.,

1987). Gehrels and Miller (2000) analyzed six detrital zircons from the Baird Formation, ranging from 326-320 Ma in age, which are slightly older than the bulk of Ph2 zircons, but with some overlap (Figures 11-14). Igneous sources of sediment for the

Pennsylvanian to early Permian, arc-derived Klinkit Group (Yukon-Tanana terrane) are another potential candidate (Simard et al., 2002, 2003), although much farther north.

However, it is plausible that ca. 330-280 Ma grains were originally derived from an arc segment which has since been lost to erosion, burial, and/or remelting by Mesozoic arc magmatism (e.g. Saleeby and Dunne, 2015).

While detrital zircon derivation from primary igneous rocks cannot be ruled out, the recycled sedimentary nature of Ph2 sandstones (Figure 18) may indicate derivation from preexisting sedimentary rocks. In this scenario, deep marine sedimentary rocks would have been laden with Carboniferous to early Permian zircons from a nearby arc and subsequently uplifted, eroded, and redeposited in the Holland Camp basin, beginning by ca. 273 Ma (based on Ph2 maximum depositional ages; Table 5).

44

Up to 5.5% of Ph2 zircons fall within the 600-400 Ma age bracket (Figures 11,

13, 14, 19). These may have been transported from peri-Gondwanan basement provinces

(Yucatan-Campeche and Suwanee provinces) of southern Laurentia (e.g. Blakey, 2007;

Gehrels and Pecha, 2014; Chapman et al., 2015). Ediacaran to Early Devonian plutons of the Yreka-Trinity terrane and Early Devonian plutons of the Eastern Klamath, Quesnella, and Yukon-Tanana terranes are another option (Wallin et al., 1988; Nelson and

Friedman, 2004; Nelson et al., 2006), consistent with McCloud arc provenance of most

Ph2 (ca. 380-270 Ma) detrital zircons.

Although not abundant, Precambrian zircon populations in Ph2 sandstones (DZ-1,

DZ-2, DZ-3, and DZ-4) are largely characteristic of western Laurentia, with a large peak ages at 1.75 Ga, and smaller peaks at ca. 2.6 Ga and 1.0 Ga (Figures 19, 22). It is unlikely that Laurentian basement provinces (Figure 21) have been continuously exposed throughout Earth’s history; these grains may have been recycled in the sedimentary record multiple times over hundreds of millions of years. Grains with 1.8-1.6 Ga ages are interpreted to have been originally derived from the Mojave, Yavapai, and Mazatzal provinces of the southwestern Laurentian craton. The ca. 2.6 Ma-aged grains have primary derivation from the northern Laurentian craton (Superior and Wyoming provinces, Trans-Hudson Suture, and the Peace River Arch), and the 1.3-0.9 Ga grains have primary derivation from the Grenville province (Figure 21; Gehrels et al., 1995,

2000, 2011; Li et al., 2008; Condie et al., 2009; Dickinson and Gehrels, 2009b; Amato and Mack, 2012; Gehrels and Pecha, 2014). DZ-1, DZ-3, and DZ-4 yielded traces of 1.6-

1.3 Ga and 0.9-0.6 Ga grains which may have originated in anorogenic plutons of the southwestern United States and the Ouachita-Marathon-Sonora orogenic belt,

45 respectively (Figure 21; Dickinson and Gehrels, 2003, 2009b; Poole et al., 2005; Gehrels and Pecha, 2014).

The Precambrian zircon populations in Ph2 litharenites are similar to spectra from

Neoproterozoic to Devonian Cordilleran passive margin remnants (Chapman et al., 2012,

2015), and Mississippian to Early Permian strata of the Antler foreland basin, Antler overlap assemblage, and the Golconda allochthon (Gehrels and Dickinson, 2000; Riley et al., 2000). Circa 2.6 Ga and ca. 175 Ga peaks in Ph2 samples resemble those of other continental rise to abyssal plain facies assemblages, including the Roberts Mountains allochthon, Kern Plateau pendants of the El Paso terrane, and the Golconda allochthon; the Ph2 ca. 1.0 peaks mirror those of the White-Inyo Mountains and Death Valley strata, which also have lesser ca. 2.6 Ga and 1.75 Ga peaks (Figure 22). Recycling of zircons from these sources is consistent with the recycled orogenic nature of Ph2 litharenites

(Figure 18) and would require a much shorter transport distance (<200 km) than if they were derived from Precambrian basement provinces (Figure 21). DZ-1 and DZ-2 have 0-

12% Precambrian grains (Figures 11, 12); Precambrian ages make up nearly 50% of all dated grains in DZ-3 and DZ-4 (Figures 13, 14). These grains may have become increasingly available due to continued uplift of sedimentary rocks with the onset of plate convergence. The hypothesis that Precambrian grains have undergone multiple episodes of transport, deposition, and recycling within the Laurentian interior is further supported by the correlation between the abundances of both Precambrian ages and more-rounded zircon morphologies in the DZ-3 and DZ-4 zircon populations, as well as an increase in rounded quartz grains in upper Ph2 strata (Figure 10).

46

Results from Ph4 sandstones (DZ-5 and DZ-6) show that the overwhelming majority of zircons were derived locally from a middle to late Permian (ca. 277-255 Ma) magmatic source (Figures 19, 20). DZ-5 and DZ-6 yielded tight, unimodal peaks at ca.

264 Ma and 267 Ma, respectively. These samples also contain volcanic lithic fragments and euhedral plagioclase, which are characteristic of arc-derived sediments (Marsaglia and Ingersoll, 1992; Rains et al., 2012). Peak ages are broadly comparable to Permian plutons in Sonora, Mexico and elsewhere in the El Paso Mountains (Miller et al., 1995;

Carr et al., 1997; Arvizu et al., 2009; Cecil et al., 2016; Ferrer et al., 2016). Therefore, it is interpreted that the nascent continental arc along southwestern Laurentia was the primary contributor of grains to the basin, with minor influxes of older grains into the basin recycled from Ph2-equivalent strata or older rocks along the continental margin. If the location of the continental arc was to the east of the basin, it is plausible that the arc highland served as a topographical barrier and drainage divide that impeded the influx of sediment from the Laurentian interior, including any Precambrian zircons derived from characteristically Laurentian basement rocks (Figures 19, 21, 22).

Although Permian age peaks on the probability distribution functions for Ph4 sandstones are at least 15 Myr younger than those of Ph2 sandstones, it is difficult to distinguish between these sources by other means. Permian zircons are sub-angular to angular, and zoned throughout all samples. Th/U ratios for are similar throughout, with a slightly higher values in Ph2 grains (Appendix D). However, the lithological character of the host rock differs significantly between Ph2 and Ph4 sandstones (Figure 18); Ph2 grains were probably derived from a separate source than Ph4 grains, but it cannot be

47 ruled out that all Permian grains were derived from a single, long-standing magmatic source.

There is a relative lull in ages between what are interpreted as the Carboniferous to early Permian source and the separate middle-late Permian source from ca. 280-275

Ma (Figure 20). If Permian zircons in the Ph4 volcaniclastic strata were all derived from the same source (i.e. the continental arc along southwestern Laurentia), then the minimum age of the earliest magmatism in that source can be determined with more statistical reliability by calculating the weighted mean of the oldest cluster of three or more ages that overlap at 2σ (OC2σ(n)) in the stratigraphically lowest Ph4 detrital zircon samples (DZ-5). This is similar in concept to the YC2σ(n) maximum depositional age calculations of Dickinson and Gehrels (2009a). DZ-5 has an OC2σ(n) age of 274.6 ± 2.2

Ma, where n = 8. This date overlaps with the ca. 275 Ma zircon U-Pb age of the oldest pluton exposed in the El Paso terrane (Cecil et al., 2016; Ferrer et al., 2016), and further supports the provenance link between Ph4 strata and the Permian continental arc along southwestern Laurentia.

Tectonic and Paleogeographic Reconstruction

The Permian Holland Camp strata of the El Paso Mountains recorded a major transition in the tectonic and paleogeographic setting of the southwestern Laurentian margin. Many workers have proposed that the Cordilleran passive margin was fragmented in the late Paleozoic Era by a left-lateral transform system (i.e. the California-

Coahuila transform), which served as the locus of convergence between Panthalassan oceanic crust and Laurentian continental crust, leading to the development of a west-

48 facing subduction zone and continental arc (e.g. Davis et al., 1978; Burchfiel and Davis,

1981; Walker, 1988; Martin and Walker, 1995; Dickinson and Lawton, 2001; Saleeby,

2011). This is the “current paradigm” (Saleeby and Dunne, 2015). The following section discusses the significance of the Holland Camp strata and implications for terrane reorganization, Permian paleogeography, and subduction initiation.

It has been proposed that the El Paso terrane, which includes Paleozoic metasedimentary rocks of the El Paso Mountains, was translated southward approximately 400 km from the latitude of Mono Lake in late Paleozoic time, based on comparisons between the lithologies and detrital zircon spectra of Cambrian to

Carboniferous rocks in the El Paso terrane and the Antler orogenic belt (Poole, 1974;

Poole et al., 1980; Stevens et al., 2005; Chapman et al., 2015). The results of this study also support the hypothesis that the El Paso Mountains are part of an allochthonous, fault- bound terrane.

Southeastward translation of the Holland Camp basin along the California-

Coahuila transform could explain the provenance trends reflected in both the petrology and detrital zircon spectra of Ph1 and Ph2 strata (Figures 10, 18, 19, 20, 22). With the El

Paso terrane’s current geographic position in the Mojave desert, it is surrounded by

Paleozoic rocks of continental affinity in the Mojave block (Chapman et al., 2012; 2015).

Initial Ph2 detrital zircon spectra (DZ-1 and DZ-2), dominated by ca. 330-280 Ma ages, have more of an affinity to offshore arc sources than cratonic sources (Figures 11, 12, 19, see the discussion of detrital zircon provenance). Syntheses of Paleozoic to modern tectonics along western Laurentia (Dickinson, 2000, 2004; Saleeby and Dunne, 2015), show that there is no known evidence of a late Paleozoic offshore arc directly west of the

49 thin passive margin along the Mojave segment (e.g. Snow, 1992). Therefore, the primary sources of these zircons are herein interpreted to be the McCloud arc terranes, at least 500 km to the northwest in the northern Sierra Nevada and Klamath mountains of northern

California.

Published U-Pb zircon ages, whole-rock geochemistry, and isotopic data for late

Permian to Jurassic plutons in the El Paso terrane indicate the El Paso terrane was thrust onto continental crust and proximal passive margin rocks in the Mojave region (Miller et al., 1995) from at least 100 km to the west (Stevens et al., 2005). From this location, the general N-S trajectory between the Holland Camp strata and the McCloud arc terranes intersects the proposed trace of the California-Coahuila transform system, with the

Northern Sierra and Eastern Klamath terranes on the opposite side (Figure 1; Dickinson and Lawton, 2001; Chapman et al., 2012, 2015). Reversing approximately 400 km of left- lateral translation along the California-Coahuila transform system places the Holland

Camp strata in closer proximity to the reconstructed location of the Northern Sierra and

Eastern Klamath terranes (Stevens et al., 2005; Blakey, 2007; Colpron et al., 2007).

Although the Permian locations of those terranes are uncertain, most workers agree that they had accreted onto the Laurentian margin by Early Triassic time (e.g. Dickinson,

2000, 2004; Colpron et al., 2007; Saleeby and Dunne, 2015), shortly after the depositional timeframe of the Holland Camp strata (ca. 280-250; Figure 17).

The initiation of transform displacement is thought to have occurred in the

Carboniferous (e.g. Walker, 1988; Dickinson and Lawton, 2001), prior to deposition within the Holland Camp basin (Figure 17). From the ages and distribution of Permian to

Triassic plutons in southern California and structural deformation of the Garlock

50 assemblage (Christiansen, 1961; Miller et al., 1995; Barth et al., 1997; Carr et al., 1997;

Barth and Wooden, 2006; Arvizu et al., 2009; Cecil et al., 2016; Ferrer et al., 2016), it is inferred that the Holland Camp basin and underlying El Paso terrane underwent minimal latitudinal translation after the Lopingian Epoch (260-252 Ma), and became part of the overriding plate of nascent subduction zone (e.g. Chapman et al., 2015; Saleeby and

Dunne, 2015).

Christiansen (1961) placed a late Permian age for thrusting and folding of the

Garlock assemblage. If the Holland Camp strata were not deposited on top of the rest of the Garlock assemblage, they must have been juxtaposed and subsequently folded within an extremely short time frame (<3 Myr) following Ph4 and Pgg deposition in Lopingian to Early Triassic time (see the discussion of maximum depositional ages; Table 5).

Therefore, it is most logical that the Holland Camp strata were deposited over local equivalents of the underlying units, including Cambrian to Pennsylvanian strata of the

Garlock assemblage (Colorado Camp, Apache Mine, and Benson Well strata), and juxtaposed against the underlying units by Mesozoic contraction in the forearc region.

Saleeby and Dunne (2015) posited that subduction initiation occurred at ca. 255

Ma along the Foothills suture, based on the estimated timing of high-pressure metamorphism in the Foothills ophiolite belt (Figure 1; Saleeby, 2011). However, the concentrated detrital zircon ages in Ph4 arc-derived sandstones and recent U-Pb zircon ages for plutons in the El Paso Mountains (Cecil et al., 2016; Ferrer et al., 2016) indicate that arc magmatism began in the Mojave region by ca. 275 Ma (Figures 15, 16).

Considering the geodynamic model for subduction initiation along prior transform faults by Gurnis et al. (2004), which proposes a window of approximately 10 Myr between

51 initial descent of the down-going slab and subsequent arc magmatism, subduction inception may have occurred as early as ca. 285 Ma. High-pressure metamorphism recorded in the Foothills ophiolite belt may have recorded later metamorphism above subducting Panthalassan lithosphere at ca. 255 Ma. If subduction inception occurred at ca. 285 Ma, then subduction would have been underway while the Holland Camp strata were deposited, and uplift and subsidence reflected in these strata would have been controlled by nascent subduction tectonics (Rains et al., 2012).

Throughout Sections 2 and 3, reflections of vertical tectonics appear to be broadly consistent with those of Section 1. Rains et al. (2012) invoked local uplift (basal conglomerate), followed by subsidence (turbidites) and deep marine sedimentation

(argillite) on the overlying plate of a nascent subduction zone to explain the facies trends seen in Ph1 and Ph2 strata (previously Pha) of Section 1 (Figure 5). However, the Ph2 channelized sandstone and conglomerate lithofacies in Sections 2 and 3 (Figures 6, 7), lying along strike to Ph2 argillite lithofacies in Section 1 (Figure 8), indicate a distinct interval of incision and subsequent coarse clastic deposition prior to shallowing and the influx of lavas flows and volcaniclastic detritus. Therefore, a second, more extensive phase of subaerial uplift, involving a larger variety of source rocks in the drainage basin may have been caused by compression between the overriding plate and subducting slab, followed by renewed subsidence prior to construction of arc edifice along the continental margin.

A speculative reconstruction of the tectonic and paleogeographic evolution along the southwestern margin of Laurentia is shown in Figure 23. This reconstruction includes three phases: A) left lateral transform faults cutting across the Cordilleran passive margin

52 and McCloud arc system in Middle Pennsylvanian to early Cisuralian time (ca. 310-390

Ma), B) transpression, incipient subduction, and Ph1-Ph2 deposition along this left lateral transform system in late Cisuralian to Guadalupian time (ca. 280-265 Ma), and C) nascent subduction, continental arc volcanism, and Ph3-Ph4 deposition in Lopingian to

Early Triassic time (ca. 260-250 Ma). See the figure caption for references used in this reconstruction.

Deposition within the Holland Camp basin began by Cisuralian time (ca. 280 Ma) with the creation of deep marine accommodation space along the southwestern edge of the broader Golconda back-arc basin, between the McCloud arc system and the Antler orogenic belt (Figure 23A; Dickinson, 2000). The California-Coahuila transform fault, translated crustal blocks in the southeastward direction and separated the Holland Camp basin from the remainder of the back-arc basin to the northeast (Saleeby, 2011; Saleeby and Dunne, 2015). The deep marine basin received chert-rich detritus (Ph1) from nearby, uplifted deep marine sedimentary rocks offshore of Laurentia, possibly from an intrabasinal high (Figure 23B; e.g. Gurnis et al., 2004; Rains et al., 2012).

Ph2 records deposition of fine-grained hemipelagic and channelized coarse clastic sediments composed of recycled marine rocks with detrital zircons derived from the

McCloud arc system or another Panthalassan arc. An uplifted deep marine sedimentary succession may have previously been loaded with detrital zircons from the McCloud arc system (Figures 18-20, 23A). Products of ca. 330-280 Ma magmatism along the southern margin of Laurentia are poorly documented, most likely due to a combination of deep burial beneath the Mesozoic Sierra Nevada arc and re-melting by associated magmatic episodes. However, recent paleogeographic constructions have envisioned a cuspate

53 island arc along the southern terminus of the McCloud arc system, as pictured in Figure

23A (e.g. Blakey, 2007; Colpron et al., 2007). It is uncertain whether the source of these zircons was actually an extension of the McCloud arc system, or geographically and tectonically distinct. However, it is inferred that the Holland Camp basin was originally in closer proximity to this arc system than the southwestern margin of Laurentia.

Through late Cisuralian and Guadalupian time (ca. 280-265 Ma), transpressional uplift along the California-Coahuila transform system created highlands where drainages supplied recycled sedimentary detritus including Precambrian detrital zircons from the

Roberts Mountains allochthon, White-Inyo range, and Death Valley facies rocks, as the

Holland Camp basin was actively being translated past these sources (Figures 19, 22,

23B). Uplift of these western sources could be linked to early Permian movement along the Last Chance thrust (Stevens and Stone, 2005a) and middle to late Permian movement along the Sierra Nevada-Death Valley thrust system (Stevens and Stone, 2005b) in eastern California. Ph2 Precambrian grains may also have been derived from local uplift within the El Paso terrane (Figures 22, 23B).

With the transition from Ph2 to Ph3 deposition, the Holland Camp basin became part of a forearc or intra-arc basin between an active trench to the west and the Laurentian coast to the east (Figure 23C). Fine-grained turbidites may have been triggered by a multitude of slip events along strike-slip and thrust faults in the surrounding area. If volcanism in the southwestern Laurentian arc was occurring, its effects were not recorded in the Holland Camp basin at this time.

In Lopingian time (ca. 260), as volcanism in the nascent continental arc along southwestern Laurentia increased, the wall rocks of the arc were mantled by lava flows

54 and para-contemporaneous sediment. Sediment was eroded from primary volcanic rocks and transported into Ph4 deposits on a narrow continental shelf (Figures 18-20, 23C).

Explosive eruptions and/or slip events along nearby faults may have triggered sediment dispersal into the Holland Camp basin. The decreasing abundance of sediment of cratonic character (i.e. coarse monocrystalline quartz and Precambrian zircons) in Ph4 strata

(Figures 10, 18), suggests that the drainage patterns from the continental interior may not have connected with the Holland Camp basin. The continental arc may have acted as a topographic or bathymetric barrier along the Mojave segment of the margin, possibly bordered by a small inland sea to the east, which trapped sedimentary input from the

Laurentian interior (Figure 23C). Modern analogs for this tectonic setting include the

Kamchatka Peninsula of eastern Russia and the Aleutian Range of Alaska.

55

Conclusions

New stratigraphic, petrologic, and detrital zircon geochronologic investigations of the Permian Holland Camp strata of the El Paso Mountains provide important constraints on reconstructions of Permian paleogeography and tectonics in the North American

Cordillera. The hypothesis that the Holland Camp strata were deposited in a Permian borderland-type setting, characterized by rapid uplift and subsidence of underlying marine basement rocks (Stone and Stevens, 1984, 1988; Stevens and Stone, 1988;

Walker, 1988; Rains et al., 2012) is supported by the results of this study. In the model presented herein, the Holland Camp strata were deposited on a crustal block that was actively translating from the northwest along the California-Coahuila transform system while an east-dipping subduction zone was developing along the southwestern margin of

Laurentia during the Permian Period. The shift from borderland style to arc-related sedimentation is reflected in all three stratigraphic sections throughout the central El Paso

Mountains (Figures 5-10, 18). The Holland Camp strata are divided into four lithologic units, based on interpreted changes in the depositional environment and reflections of uplift and subsidence trends on the overlying plate of a nascent subduction zone.

Ph1 strata are late Cisuralian (ca. 280 Ma) deep marine sedimentary rocks deposited offshore of the Laurentian margin. They consist of conglomerate, calcareous hemipelagic sediments, and channels and lobes of sandy limestone. Lithic clasts in these deposits were derived from chert-rich, deep-marine sedimentary rocks uplifted within the vicinity of the basin, possibly owing to transpression and/or the initiation of subduction beneath southwestern Laurentia.

56

Ph2 strata are siliciclastic deep marine sedimentary rocks, including a thick (up to

256 m) package of argillite, with channelized deposits of litharenite and conglomerate.

Infilling of the channels probably occurred ca. 273 Ma, with recycled detritus from a variety of marine sedimentary rocks, and a mixture of Carboniferous to Permian zircons recycled from an marine sedimentary rocks along an offshore arc, and Precambrian zircons recycled from Paleozoic passive margin deposits along the craton edge. The coarse clastic supply for these deposits corresponds to a second period of uplift in the drainage basin, possibly related to subduction initiation and/or transpression along and offshore of the continental margin.

Ph3 strata are laterally extensive deep-marine deposits, composed predominantly of calc-argillite and calc-siltstone turbidites, and limestones bearing fossils transported from shallower regions of the basin.

Ph4 includes abundant feldsarenite and volcaniclastic strata with some carbonate beds similar to those of Ph3. These strata were deposited after ca. 258 Ma, during the

Lopingian Epoch, adjacent to a coeval volcanic arc. Ph4 detrital zircon spectra have ca.

275-255 Ma zircons, with tight, unimodal peaks at ca. 267-264 Ma. These zircons are comparable in age to plutons in the northwestern Mojave region, particularly those of the

El Paso Mountains (Barth and Wooden, 2006; Cecil et al., 2016; Ferrer et al., 2016), and are interpreted to have been derived from the Permian continental arc along southwestern

Laurentia. Pgg andesitic lavas were fed into the Holland Camp basin from the nascent continental arc and covered Ph4 volcaniclastic strata.

57

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Appendix A

Table Captions

Table 1: Table of conglomerate clast count results comparing the lithologies, clast shapes and sizes, and clast compositions of five conglomeratic beds of the Holland Camp strata. See Figures 3, 5, 6, 8, and 9 for more information on clast counts.

Table 2: Petrographic descriptions and other information for all thin sections of metasedimentary and metavolcanic in this study. Samples marked with an asterisk (*) were stained for potassium and calcium-rich mineral recognition. Abbreviations are defined at the bottom of the table.

Table 3: Sandstone petrography point count results for eleven samples. Each sample was reassigned a PC number in ascending stratigraphic order. In each analysis, 300 points were counted.

Table 4: Formulas and recalculated parameters from the sandstone petrographic point count results (Table 3) for plotting on QtFL, QmFLt, QmKP, and QpLvLs ternary diagrams (Figure 10), after Dickinson et al. (1983), Dickinson (1985), and Marsaglia and Ingersoll (1992).

Table 5: Detrital zircon sample information and maximum depositional ages calculated using TuffZirc(n) on the youngest graphical peak, and YC2σ(n) and YC2σ(n), after Dickinson and Gehrels (2009a). All maximum depositional ages are presented with a 95% confidence interval (1.96σ). Abbreviations: Spect. = age spectrum; Sec. = stratigraphic section; sed. = sedimentary; SH = stratigraphic height (m); and n = number of grains used in maximum depositional age calculations.

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Table 1: Conglomerate Clast Count Results

CC-1 CC-2 CC-3 CC-4 CC-5

Unit Ph1 Ph2 Ph4 Strat. 1 2 2 2 2 Section Strat. 30 247 318 419 753 Height (m) GPS N 35° 26.773' N 35° 26.510' N 35° 26.510' N 35° 26.438' N 35° 26.286' Lat./Lon. W 117° 47.497' W 117° 47.235' W 117° 47.206' W 117° 47.134' W 117° 46.828' Thin n/a EM15-23 EM15-25 EM15-29 EM15-39 Section Sedimentary- Sedimentary- Sedimentary- Volcanic- Chert-clast Lithology clast clast clast bearing conglomerate Conglomerate Conglomerate Conglomerate conglomerate Max. Cobble Cobble Cobble Boulder Cobble clast size Sub-angular/ Sub-angular/ Sub-angular/ Sub-angular/ Clast shape Sub-angular Sub-rounded Sub-rounded Sub-rounded Sub-rounded Chert 99 38 58 56 14

Siltstone/ 1 32 33 28 9 argillite Carbonate 0 0 0 5 38

Quartz 0 30 9 11 0 arenite Felds- 0 0 0 0 12 arenite Aphanitic 0 0 0 0 13 volcanic Porphyritic 0 0 0 0 4 andesite Total 100 100 100 100 100

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Table 2: Locations and Descriptions of Thin Sectioned Samples

Texture/ GPS Grain Sed. Unit Sec. S.H. Sample Lat./Lon. Lithology size Structure Sort. Round. Matrix Minerals Lithic clasts Bioclasts N 35° 26.127' Cl, Zlt, Pgg EM15-01 andesite microlitic subh P (c), Amph (m) W 117° 46.502' Opq P (p), Qm (m), N 35° 26.222' volcaniclastic f. - m. mod- Ph4 2 797 EM15-12 suba Cl, mica Cal (m), FeOx Lv ml (m), Qp (t) W 117° 46.753' arenite sand well (m) volcanic- P (p), Cal (c), Lv g (c), Ls arg N 35° 26.286' f. sand - volcani- suba- Ph4 2 753 EM15-39* bearing poor Cl, mica Qm (m), FeOx (m), Ls ss (t), Qp W 117° 46.828' peb clastic subr conglomerate (t) (t) EM15-38 P (c), Qm (c), Qp (c), Lv g (m), crinoids, N 35° 26.178' calcareous mod- suba- Cl, mica, Ph4 2 682 (DZ-6, Cal (c), FeOx Ls argl (t), Lv lw sponge W 117° 46.822' feldsarenite well subr Opq PC-11) (m) (t) spicules Qp (c), Ls arg (m), Ls carb (t), EM15-11 N 35° 26.368' plagioclase f. - m. mod- P (a), Qm (c), Ph4 2 675 suba Cl, mica Ls slt (t), Lv g echinoderm(?) (PC-10) W 117° 46.913' feldsarenite sand well FeOx (c), Cal (c) (m), Lv lw (t), Lv ml (t) P (c), Cal (a), Qp (m), Lv g (m), Phc-2* N 35° 26.826' calcareous silt - m. mod- Qm (m), FeOx Ph4 1 674 suba Cl, mica Ls arg (t), Lv lw (PC-9) W 117°46.895’ feldsarenite sand well (t), zircon (t), (t) garnet (t) N 35° 26.369' fossiliferous f. sand - mod- Cal (p), Qm (m), crinoids, Ph3 2 664 EM15-36 subr Cl, mica Qp (m), Lv ml (t) W 117° 46.920' limestone gran poor FeOx (t) fusulinid sandy bryozoans, N 35° 26.411' f. - c. suba- Cal (p), Qm (c), Ph3 2 597 EM15-34 fossiliferous mod Cal, Opq Qp (c), Ls slt (m) crinoids, W 117° 46.979' sand subr FeOx (t) limestone foram(?) N 35° 26.422' fossiliferous silt - Cal (p), Qm (m), Qp (m), Ls slt bryozoans, Ph3 2 531 EM15-32 mod subr Cal, Opq W 117° 47.030' limestone peb FeOx (t) (m), Lv ml (t) crinoids EM15-10* N 35° 26.422' quartzose sed. f. - m. matrix- suba- Qm (p), P (c), Ph2 2 485 mod Cl, mica Qp (m), Ls ss (t) spore(?) (PC-8) W 117° 47.062' litharenite sand supp subr Cal (c), FeOx (t) Qp (a), Ls arg EM15-13 N 35° 25.905' f. - c. mod- suba- Cl (t), Qm (c), P (c), (m), Ls slt (t), Ls Ph2 3 480 sed. litharenite (PC-7) W 117° 46.897' sand poor subr mica FeOx (m) ss (t), Lv lw (t), Lv ml (t)

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Texture/ SH GPS Grain Sed. Unit Sec. (m) Sample Lat./Lon. Lithology size Structure Sort. Round. Matrix Minerals Lithic clasts Bioclasts crinoid/echinoi ds, rugose coral, EM15-41* bioclast- Cal (c), Qm (m), Qp (a), Ls arg (c), N 35° 26.432' f. sand - suba- Cl, Cal, foram(?), Ph2 2 468 (DZ-4, bearing sed. clast-supp poor P (c), FeOx (m), Ls slt (m), Lv g W 117° 47.073' gran subr Opq sponge PC-6) litharenite zircon (t) (m), Ls ss(t) spicules, bryozoans(?), brachiopoda Qp (a), Ls ss (c), EM15-29* N 35° 26.438' sed.-clast m. sand matrix- v. suba- Cl, mica, Qm (a), Cal (c), Ph2 2 419 Ls slt (m), Ls arg (CC-4) W 117° 47.134' conglomerate - peb supp poor subr Cal p (m) (t) Qm (c), FeOx Qp (a), Ls arg EM15-09 N 35° 26.463' suba- Ph2 2 403 sed. litharenite f. sand well Cl, mica (c), P (m), Cal (m), Ls slt (t), Ls (PC-5) W 117° 47.135' subr (m) ss (t), Lv g (t) Qm (c), Cal (m), EM15-28* N 35° 26.461' quartzose sed. silt - f. suba- Cl, mica, FeOx (m), P (m), Qp (a), Ls slt (t), spore (?), Ph2 2 394 (DZ-3, burrows well W 117° 47.140' litharenite sand subr Opq zircon (t), Lv g (t) sponge spicule PC-4) tourmaline (t) Qp (a), Ls slt (c), EM15-26 N 35°26.447' m. sand Qm (c), P (c), Ph2 2 376 sed. litharenite grain-supp poor subr Cl, Opq Ls ss (m), Ls arg (PC-3) W 117°47.156' - gran FeOx (m) (m), Lv g (t) Ls ss (c), Qp (c), EM15-25* N 35° 26.510' sed.-clast f. sand - v. suba- Qm (c), Cal (m), Ls slt (c), Ls arg Ph2 2 318 clast-supp Cl, mica (CC-3) W 117° 47.206' conglomerate peb poor subr FeOx (t) (m), Lv lw (t), Lv g (t) Qp (p), Ls slt (c), EM15-04* Qm (r), P (m), N 35°26.513’ f. - c. suba- Lv ml (m) Qp crinoids, Ph2 2 294 (DZ-2, sed. litharenite clast-supp mod Cl, mica Cal (m), FeOx W 117°47.215’ sand subr spic (t), Ls ss (t), possible spore PC-2) (m), zircon (t) Lv g (t) Qp (c), Ls ss (c), EM15-23* N 35° 26.510' sed.-clast f. sand - matrix- v. suba- Qm (m), Cal (t), Ph2 2 247 Cl, mica Ls slt (c), Ls arg (CC-2) W 117° 47.235' conglomerate peb supp poor subr P (t), FeOx (r) (m) Qm (c), P (m), EM15-42 Qp (a), Ls slt (t), N 35° 26.510' f. sand - suba- Cl, mica, FeOx (r), Cal (t), Ph2 2 239 (DZ-1, sed. litharenite mod Ls arg (t), Ls ss crinoids (t) W 117° 47.245' gran subr Opq K (t), zircon (t), PC-1) (t), Lv ml (t) titanite (t) N 35° 26.554' f. sand - matrix- Cal-Dol (p), Qm Ph1 2 206 EM15-20 limestone poor subr Cal, Opq Qp (t) W 117° 47.280' peb supp (t)

Continued on the next page.

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Texture/ SH GPS Grain Sed. Unit Sec. (m) Sample Lat./Lon. Lithology size Structure Sort. Round. Matrix Minerals Lithic clasts Bioclasts N 35° 26.773' chert-clast silt - v. silty, Qp (p), Qp spic Ph1 1 30 EM15-16 clast-supp suba Qm (t), Feox (t) W 117° 47.497' conglomerate peb poor Opq (m), Ls slt (m) N 35° 26.625' f. sand - mod- Cal (p), Qm (t), Ph1 2 26 EM15-08 limestone r-suba Cl, Cal Qp (m) W 117° 47.412' peb. poor FeOx (t) N 35° 26.612' sandy f. sand - matrix- Cal (p), Qm (m), Ph1 2 20 EM15-18 poor suba Cal Qp (c), Ls slt (m) crinoids W 117° 47.421' limestone gran supp FeOx (t) Benson Well strata N 35° 26.680' suba- EM15-15 cherty siltstone silt foliated well Cl, mica Qm (a) Qp (p) (Pennsylvanian) W 117° 47.558' subr Qp (p), Ls slt (c), Benson Well strata N 35° 26.618' chert-clast f. sand - v. EM15-14 grain-supp r-subr Cl, mica Qm (c) Ls ss (m), Ls arg (Pennsylvanian) W 117° 47.535' conglomerate peb poor (m) Apache Mine strata N 35° 25.697' f. sand - suba- Qm (m), Biot (t), Qp (p), Ls slt (c), EM15-43* chert litharenite grain-supp poor Cl, mica (Mississippian) W 117° 47.015' peb subr FeOx (t) Ls ss (m) Apache Mine strata N 35° 25.151' quartz mod- Qm (p), Cal (t), EM15-40 f. sand subr-r Cl Qp (a) (Mississippian) W 117° 46.533' litharenite well FeOx (t) Apache Mine strata N 35° 26.654' EM15-03 chert clay-silt well Quartz Qm (t) Qp (p) (Mississippian) W 117°47.674’

Abbreviations Sec. = stratigraphic section, SH = stratigraphic height, Sed. = sedimentary, Grain size: c. sand = coarse sand, f. sand = fine sand, gran = granule, m. sand = medium sand, peb = pebble. Grain-supp = grain supported, Matrix-supp = matrix supported. Sorting (Sort.): mod. = moderately, v. = very. Rounding (Round.): suba = sub-angular, subh = subhedral, subr = sub-rounded, r = rounded.

Minerals and Lithic Clasts: Amph = amphibole, Biot = biotite, Cal = calcite, Cal-Dol = calcite-dolomite, Cl = chlorite, FeOx = iron oxide, K = potassium feldspar, Ls arg = argillite, Ls carb = carbonate, Ls slt = siltstone, Ls ss = sandstone, Lv g = volcanic glass, Lv lw = lathwork volcanic, Lv ml = microlitic volcanic, Opq = opaque phase, P = plagioclase feldspar, Qm = monocrystalline quartz, Qp = polycrystalline quartz / chert, Qp spic = spicular chert, Zlt. = zeolite.

Abundances: (p) = predominant (>50%), (a) = abundant (30-50%), (c) = common (5-30%), (m) = minor (1-5%), and (t) = trace (<1%).

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Table 3: Sandstone Point Count Results

Unit Ph2 Ph4

1 2 3 4 5 6 7 8 9

10 11

------

- -

PC PC PC PC PC PC PC PC PC Point Count No. PC PC

42 04 26 28 09 41 13 10 11 38

2

------

-

Phc

Sample / Thin Section EM15 EM15 EM15 EM15 EM15 EM15 EM15 EM15 EM15 EM15 Detrital zircon sample (DZ-) 1 2 3 4 6 Stratigraphic Height (m) 239 294 376 394 403 468 480 485 674 675 682 Monocrystalline quartz Qm 19 10 40 72 40 7 42 156 7 31 27 Polycrystalline quartz Qpc 10 19 28 13 16 5 30 10 0 0 1 Chert Qp cht 143 154 108 125 96 103 127 5 12 24 62 Silty chert Qp slt 6 1 16 0 5 0 13 1 0 3 0 Radiolarian chert Qp rad 0 0 0 0 0 0 0 0 0 0 0 Spicular chert Qp spic 0 0 0 0 0 1 0 0 0 1 4 Plagioclase feldspar P 8 40 34 13 12 19 23 34 87 144 76 Potassium feldspar K 0 0 0 0 0 0 0 0 0 0 0 Siltstone Ls slt 1 0 26 1 1 6 0 0 0 0 0 Argillite Ls arg 0 3 4 2 10 17 4 0 2 4 2 Sandstone Ls ss 0 0 11 0 1 0 0 1 0 0 0 Limestone Ls ls 0 0 0 0 0 0 0 0 0 1 0 Bioclastic fragments Bioc 0 3 2 0 5 25 2 2 4 3 3 Volcanic glass Lv g 0 0 1 0 0 1 0 0 2 0 2 Lathwork volcanic lithic Lv lw 0 0 6 0 0 0 2 0 2 2 2 Microlitic volcanic lithic Lv ml 2 2 0 0 0 0 1 0 0 1 0 Altered volcanic lithic Lv alt 2 1 1 1 10 6 0 0 3 3 2 Calcite (recrystallized) Cal 0 14 0 11 9 49 0 15 91 15 63 Biotite Biot 4 0 0 0 1 0 0 0 0 0 0 Muscovite Musc 0 0 0 1 1 0 0 0 0 0 0 Chlorite Chl 5 0 0 0 0 0 2 0 1 0 0 Iron Oxide (alteration) FeOx 5 9 5 15 18 9 4 2 1 16 6 Dense minerals DM 3 2 0 0 0 1 0 0 1 0 0 Matrix 92 42 18 46 75 51 50 50 87 52 50 Total 300 300 300 300 300 300 300 300 300 300 300

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Table 4: Formulas and Recalculated Parameters

Qt = Qm + Qpc + Qp cht + Qp silt + Qp rad + Qp spic Qp = Qpc + Qp cht + Qp silt + Qp rad + Qp spic F = P + K Lv = Lv g + Lv lw + Lv ml + Lv alt Ls = Ls slt + Ls arg + Ls ss + Ls ls L = Ls + Lv Lt = L + Qp

QtFL %Qt = 100 × Qt / (Qt + F + L) %F = 100 × F / (Qm + F + Lt) %L = 100 × L / (Qt + F + L)

QmFLt %Qm = 100 × Qm / (Qm + F + Lt) %F = 100 × F / (Qt + F + L) %Lt = 100 × Lt / (Qm + F + Lt)

QpLvLs %Qp = 100 × Qp / (Qp + Lv + Ls) %Lv = 100 × Lv / (Qp + Lv + Ls) %Ls = 100 × Ls / (Qp + Lv + Ls)

QmKP %Qm = 100 × Qm / (Qm + K + P) %K = 100 × K / (Qm + K + P) %P = 100 × P / (Qm + K + P)

QtFL QmFLt QpLvLs QmKP PC- %Qt %F %L %Qm %F %Lt %Qp %Lv %Ls %Qm %K %P 1 93.2 4.2 2.6 9.9 4.2 85.9 97.0 2.4 0.6 70.4 0.0 29.6 2 80.0 17.4 2.6 4.3 17.4 78.3 96.7 1.7 1.7 20.0 0.0 80.0 3 69.8 12.4 17.8 14.5 12.4 73.1 75.6 4.0 20.4 54.1 0.0 45.9 4 92.5 5.7 1.8 31.7 5.7 62.6 97.2 0.7 2.1 84.7 0.0 15.3 5 82.2 6.3 11.5 20.9 6.3 72.8 84.2 7.2 8.6 76.9 0.0 23.1 6 87.6 9.5 2.9 17.4 9.5 73.1 96.0 1.7 2.3 64.6 0.0 35.4 7 70.3 11.5 18.2 4.2 11.5 84.2 78.4 5.0 16.5 26.9 0.0 73.1 8 83.1 16.4 0.5 75.4 16.4 8.2 94.1 0.0 5.9 82.1 0.0 17.9 9 16.5 75.7 7.8 6.1 75.7 18.3 57.1 33.3 9.5 7.4 0.0 92.6 10 27.6 67.3 5.1 14.5 67.3 18.2 71.8 15.4 12.8 17.7 0.0 82.3 11 52.8 42.7 4.5 15.2 42.7 42.1 89.3 8.0 2.7 26.2 0.0 73.8

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Table 5: Detrital Zircon Sample Information and Maximum Depositional Age Calculations

SH GPS Thin Point Lithology TuffZirc(n) Peak YC2σ(n) YC1σ(n) Unit Spect. Sec. (m) Lat./Lon. Section Count n Age (Ma) n Age (Ma) n Age (Ma)

N 35° 26.178' calcareous DZ-6 2 682 W 117° 46.822 EM15-38 11 feldsarenite 88 266.3 +1.0 -1.3 7 255.5 ± 2.3 3 253.8 ± 3.5

Ph4

N 35° 26.839' volcaniclastic DZ-5 1 665 W 117° 46.912' n/a n/a arenite 30 262.3 +2.1 -2.9 13 258.0 ± 1.5 8 256.9 ± 2.0

bioclast- N 35° 26.432' bearing sed. DZ-4 2 468 W 117° 47.073' EM15-41 6 56 294.6 +5.9 -6.4 4 263.0 ± 10 3 259.0 ± 13 litharenite

N 35° 26.461' quartzose sed. DZ-3 2 394 W 117° 47.140' EM15-28 4 litharenite 44 296.6 +8.1 -13 10 264.3 ± 7.6 5 260.7 ± 9.9

Ph2

N 35° 26.513’ sed. litharenite DZ-2 2 294 W 117° 47.215’ EM15-04 2 100 297.6 +1.1 -3.4 19 281.2 ± 4.6 3 271.0 ± 12

N 35° 26.510' sed. litharenite DZ-1 2 239 W 117° 47.245' EM15-42 1 49 293.1 +3.0 -5.0 19 283.3 ± 5.4 2 249.0 ± 15

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Appendix B

Figure Captions

Figure 1: Regional tectonic map of the southwestern United States and northeastern Mexico, modified after Dickinson (2000, 2004), Dickinson and Lawton (2001), and Chapman et al. (2015). Early Paleozoic passive margin trends have a northeast trend, sub- parallel to the craton hinge. This pattern has been disrupted in California and Sonora, with portions of the northeast-trending margin displaced by late Paleozoic sinistral transform motion. The locations of Permian-Triassic plutons are from Barth and Wooden (2006), can Carr et al. (1997). Geographic abbreviations: AZ = Arizona; BN = Baja California (north); CA = California; and NV = Nevada. Fault abbreviations: CCT = California-Coahuila transform; FS = Foothills suture; GF = Garlock fault; GT = Golconda thrust; LCT = Last Chance thrust, RMT = Roberts Mountains thrust, SAF = San Andreas fault.

Figure 2: Geological map of the El Paso Mountains, southern California, modified after Carr et al. (1997) and overlain on a shaded relief image constructed in ArcGIS. Quaternary units were omitted for clarity. The southern edge of the range, along Fremont Valley, is structurally controlled by the Cenozoic Garlock fault. The study area is shown as a rectangular box, encompassing Holland Camp, Mormon Flat, and Iron Canyon in the central part of the range

Figure 3: Geological map of the study area in the central El Paso Mountains (shown in Figure 2) overlain onto a topographic map constructed in ArcGIS, showing the mapped contacts, stratigraphic sections, clast count locations, and detrital zircon sample locations. The location of the cross section in Figure 4 is shown by the A-A’ line.

Figure 4: A-A’ interpretive cross section of tilted and nearly homoclinal strata in the study area. See Figure 3 for the cross section line. Strata are younging to the southeast (A’). Ph1 appears to have been thrust over the Benson Well and Colorado Camp strata, thereby covering those units beneath Section 2. The slip sense on this fault is unclear, but it has been mapped as a thrust by Carr et al. (1997).

Figure 5: Stratigraphic column for Section 1 (947 m thick), modified after Rains et al., (2012) with additional findings from this study. Stratigraphic height = 0 m represents the base of the Permian Holland Camp strata (Ph1-Ph4). Conglomerate clast count, sandstone point count, macrofossil, and detrital zircon sample horizons are displayed alongside the column.

Figure 6: Stratigraphic column for Section 2 (831 m thick), normalized to the stratigraphic levels in Section 1; the base of the Permian Holland Camp strata in Section 1 is at stratigraphic height = 0 m. Conglomerate clast count, sandstone point count, macrofossil, and detrital zircon sample horizons are displayed alongside the column.

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Figure 7: Stratigraphic column for Section 3 (679 m thick), normalized to the stratigraphic levels in Section 1; the base of the Permian Holland Camp strata in Section 1 is at stratigraphic height = 0 m. Section 3 is the more structurally deformed than Sections 1 and 2, with a truncated base overlying Apache Mine strata (Ma). Sandstone point counts, macrofossil horizons, and faults are displayed alongside the column.

Figure 8: Correlation of all three stratigraphic sections from Figures 5-7 and isolated outcrops shown in Figure 3, based on the alignment of the base of Ph3 and key macrofossil-bearing limestone horizons. Faults, conglomerate clast counts, sandstone point counts, macrofossils, and detrital zircon sample horizons are displayed alongside each column. Grain size abbreviations: c. = clay, s. = sand, g. = gravel.

Figure 9: Ternary plot of conglomerate clast count data from five horizons. All conglomerate horizons fall within the sedimentary-clast conglomerate field, but vary in terms of their proportions of sedimentary clast types (carbonate, chert, and siliciclastic). The siliciclastic category is the sum of all quartz arenite, feldsarenite, siltstone, and argillite clasts.

Figure 10: Diagram of conglomerate clast count (CC) and sandstone point count (PC) results, with stratigraphic measurements of the Holland Camp strata in Section 2 (with correlations) along the ordinate and the relative abundances (%) of clast types along the abscissa. Stratigraphic measurements are normalized to those of Section 1. An = andesite, Cal = calcite (sum of detrital and authigenic, largely recrystallized), Cht = chert, Ls = limestone, P = plagioclase feldspar, Qm = monocrystalline quartz, Slt-Arg = siltstone and argillite, SsF = feldsarenite, SsQ = quartz arenite, V = fine-grained volcanic lithic fragments with aphanitic, microlitic, and lathwork textures.

Figure 11: Age probability distribution functions for detrital zircon spectrum 1 (n=113), from a Ph2 litharenite at 239 m in Section 2. The large histogram displays age abundances (3000-0 Ma) in 20 Myr intervals, and the small histogram displays age abundances (500-200 Ma) in 10 Myr intervals. The pie chart shows the relative abundances of zircon ages in intervals >1.8 Ga, 1.8-1.6 Ga, 1.6-1.3 Ga, 0.9-0.6 Ga, 0.6- 0.4 Ga, and <0.4 Ga (see Figure 19). Ages younger than 1.0 Ga are 206Pb*/238U ages, whereas older ones are 207Pb*/206Pb* ages. Zircons are primarily younger than 400 Ma with a major ca. 298 Ma peak.

Figure 12: Age probability distribution functions for detrital zircon spectrum 2 (n=113), from a Ph2 litharenite at 294 m in Section 2. The large histogram displays age abundances (3000-0 Ma) in 20 Myr intervals, and the small histogram displays age abundances (500-200 Ma) in 10 Myr intervals. All ages are based on 206Pb*/238U ratios. All zircons are younger than 340 Ma with a major ca. 296 Ma peak.

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Figure 13: Age probability distribution functions for detrital zircon spectrum 3 (n=151), from a Ph2 quartzose litharenite at 394 m in Section 2. The large histogram displays age abundances (3000-0 Ma) in 20 Myr intervals, and the small histogram displays age abundances (500-200 Ma) in 10 Myr intervals. The pie chart shows the relative abundances of zircon ages in intervals >1.8 Ga, 1.8-1.6 Ga, 1.6-1.3 Ga, 1.3-0.9 Ga, 0.9- 0.6 Ga, 0.6-0.4 Ga, and <0.4 Ga (see Figure 19). Ages younger than 1.0 Ga are 206Pb*/238U ages, whereas older ones are 207Pb*/206Pb* ages. <400 Ma and >400 Ma ages are nearly equal in abundance. The most prominent peak is ca. 282 Ma.

Figure 14: Age probability distribution functions for detrital zircon spectrum 4 (n=110), from a Ph2 litharenite at 468 m in Section 2. The large histogram displays age abundances (3000-0 Ma) in 20 Myr intervals, and the small histogram displays age abundances (500-200 Ma) in 10 Myr intervals. The pie chart shows the relative abundances of zircon ages in intervals >1.8 Ga, 1.8-1.6 Ga, 1.3-0.9 Ga, 0.9-0.6 Ga, 0.6- 0.4 Ga, and <0.4 Ga (see Figure 19). Ages younger than 1.0 Ga are 206Pb*/238U ages, whereas older ones are 207Pb*/206Pb* ages. Zircons are primarily younger than 340 Ma with a major ca. 290 Ma peak.

Figure 15: Age probability distribution functions for detrital zircon spectrum 5 (n=44), from a Ph4 epiclastic sandstone at 665 m in Section 1. The large histogram displays age abundances (3000-0 Ma) in 20 Myr intervals, and the small histogram displays age abundances (500-200 Ma) in 10 Myr intervals. The pie chart shows the relative abundances of zircon ages in intervals >1.8 Ga, and <0.4 Ga (see Figure 19). Ages younger than 1.0 Ga are 206Pb*/238U ages, whereas older ones are 207Pb*/206Pb* ages. Almost all zircons ages are 280-240 Ma with a ca. 264 Ma peak.

Figure 16: Age probability distribution functions for detrital zircon spectrum 6 (n=121), from a Ph4 feldsarenite at 682 m in Section 1. The large histogram displays age abundances (3000-0 Ma) in 20 Myr intervals, and the small histogram displays age abundances (500-200 Ma) in 10 Myr intervals. Ages younger than 1.0 Ga are 206Pb*/238U ages, whereas older ones are 207Pb*/206Pb* ages. Almost all zircons ages are 300-240 Ma with a ca. 267 Ma peak.

Figure 17: Age correlation diagram comparing members Pha-Phc of Carr et al. (1984, 1997) and Ph1-Ph4 in this study to the international chronostratigraphic chart of Cohen et al. (2012) and Gradstein et al. (2012). Lithological correlations are shown between the units of Carr et al. (1984, 1997) and this study: Pha is subdivided into Ph1 and Ph2, Phb is roughly equivalent to Ph3, and Phc is roughly equivalent to Ph4. The depositional timeframe for the Holland Camp strata is constrained by maximum depositional ages at the base (DZ-1) and top (DZ-4) of Ph2, and at the base of Ph4 (DZ-5). The estimated “lag time” between maximum depositional ages and inferred depositional ages is represented by the vertical line between the arrowhead and the maximum depositional age.

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Figure 18: Ternary plots of point count data (Table 3), including point count data from Rains (2009). See Table 4 for parameter calculations. (A) QmFLt, after Dickinson et al. (1983), (B) QtFL, after Dickinson et al. (1983), (C) QpLvLs, after Dickinson (1985), and (D) QmKP, after Marsaglia and Ingersoll (1992). Recalculated parameters (defined in Table 4): F = total feldspar; K = potassium feldspar; L = non-chert lithic fragments; Ls = non-chert sedimentary lithic fragments; Lt = total lithic fragments; Lv = volcanic lithic fragments; Qm = monocrystalline quartz; Qp = polycrystalline quartz and chert lithic fragments; and Qt = sum of all quartz and chert lithic fragments.

Figure 19: Normalized probability plots comparing detrital zircon ages (3.0 Ga to present) from all six samples analyzed in this study. Geologic periods are from the international chronostratigraphic chart of Cohen et al. (2012) and Gradstein et al. (2012). Provenance interpretations are overlain as follows: 3.0-1.8 Ga = Northern Laurentian craton; 1.8-1.6 Ga = Mojave, Yavapai, and Mazatzal continental basement provinces; 1.6-1.3 Ga = anorogenic plutons in the United States; 1.3-0.9 Ga = Grenville and Oaxaca basement provinces; 0.9-0.6 Ga = Peri-Gondwanan provinces of the Gulf of Mexico region; 0.6-0.4 Ga = Trinity terrane of northern California; and <0.4 Ga = late Paleozoic magmatic arcs, including Panthalassan island arcs and the continental arc of southwestern Laurentia. The relative percentages of grains within each provenance age group are shown above the probability distribution functions for each sample.

Figure 20: Normalized probability plots comparing detrital zircon ages (500-200 Ma) from all six samples in this study. Lithologies, prominent peak ages, and YC2σ(n) maximum depositional ages (where n = the number of grains in each calculation) are shown for comparison. Error bars on maximum depositional ages are too small to be seen at this resolution. Ph2 samples have Cisuralian peak ages (298-282 Ma), and Ph4 samples have Guadalupian peak ages (267 Ma and 264 Ma).

Figure 21: Basement geologic provinces of North America in relationship to the El Paso Mountains (yellow star) and the late Paleozoic truncation boundary, simplified and modified after Gehrels and Pecha (2014) and Chapman et al. (2015). The national borders of Canada, United States, and Mexico are shown for geographic reference. North America map projection: Chamberlin Trimetric, courtesy of the Arizona Geographic Alliance. OK = Oklahoma; CO = Colorado.

Figure 22: Normalized probability plots comparing the combined zircon ages (3000-400 Ma) from all Ph2 litharenite samples in this study to composite spectra from Paleozoic strata of Kern Plateau pendants of the El Paso terrane, Golconda allochthon, Roberts Mountains allochthon, White-Inyo range, and Death Valley (Riley et al., 2000; Chapman et al., 2012, 2015). See Figure 1 for the present locations of these terranes.

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Figure 23: Speculative reconstruction of Middle Pennsylvanian to Early Triassic (ca. 310- 250 Ma) tectonic events along the California-Coahuila transform system. (A) Sinistral transform faulting along the California-Coahuila transform and Foothills suture, with possible magmatic activity along the southern terminus of the McCloud arc system. (B) The Holland Camp strata (Ph1-Ph2) begin to accumulate adjacent to transpressionally- uplifted blocks of older marine sedimentary rocks during active translation of the basin and subduction inception. Transpression and the initial decent of the down-going slab cause subaerial(?) uplift of the sedimentary cover sequence along the oceanic transform system, supplying the Holland Camp basin with recycled clastic detritus from multiple sources. (C) Closure of the Golconda basin and the initial accretion of the McCloud arc system and Golconda allochthon. Subduction is underway along the California-Coahuila transform system, with volcanic arc activity along the continental margin. Holland Camp strata (Ph3-Ph4) are deposited adjacent to the active continental arc along southwestern Laurentia. Regional geology from Walker (1988), Dickinson (2000), Dickinson and Lawton (2001), Stevens and Stone (2005a, 2005b), Blakey (2007), Saleeby (2011), Saleeby and Dunne (2015), and Chapman et al. (2015). AO = Antler overlap assemblage; CB = Caborca block; CCT = California-Coahuila transform; CP = Colorado plateau; DV = Death Valley sequence; DVT = Death Valley thrust system; EPT = El Paso terrane; FS = Foothills suture; GA = Golconda allochthon; GB = Golconda basin; GT = Golconda thrust; LCT = Last Chance thrust; MA = McCloud arc system; MT = Mojave thrust system; RMA = Roberts Mountains allochthon; RMT = Roberts Mountains thrust; and W-I = White-Inyo sequence.

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Appendix C

Plate Captions

Plate 1: Outcrop photos from the study area in the central El Paso Mountains (Figure 2). (A) Profile view of Section 2 (Figure 6) showing moderate to steeply-dipping contacts. (B) Profile view of the fault separating the basal Permian Holland Camp strata from the Cambrian-Ordovician Colorado Camp strata just south of the Holland Camp mine, geologist (Brittany Huerta) for scale (Figure 3). (C) Ph2 matrix-supported conglomerate, pencil for scale. (D) Ph3 calc-siltstone interbedded with calc-argillite, 5 by 7 inch notebook for scale. (E) Close-up of an outcrop of aphanitic Goler Gulch andesite.

Plate 2: Photomicrographs in both plane-polarized (PPL) and cross-polarized light (XPL). See Table 2 for petrographic descriptions. (A) Ph1 sandy limestone (EM15-18) with chert lithic fragments (Qp) in a silty, carbonate matrix. (B) Ph1 chert-clast conglomerate (EM15-16; CC-1) with sub-angular chert lithic fragments (Qp) and iron oxide alteration along fractures and throughout the matrix. (C) Ph2 sedimentary-lithic conglomerate (EM15-25; CC-3) with siltstone (Ls slt), chert (Qp), argillite (Ls arg), and possible volcanic glass (Lv g) lithic fragments and monocrystalline quartz (Qm). (D) Ph2 litharenite (EM15-42; DZ-1; PC-1) with monocrystalline quartz (Qm), carbonate (Cal), and quartzose sandstone lithic fragments (Ls ss).

Plate 3: Photomicrographs in both plane-polarized (PPL) and cross-polarized light (XPL). See Table 2 for petrographic descriptions. (A-B) Ph2 litharenite (EM15-04; DZ-2; PC-2) with monocrystalline quartz (Qm) and detrital zircon in a fine-grained, clay-rich matrix. (C) Ph2 quartzose litharenite (EM15-28; DZ-3; PC-4) with monocrystalline quartz (Qm) and chert lithic fragments (Qp) with carbonate (Cal) in the intergranular spaces. (D) Ph3 sandy fossiliferous limestone (EM15-34) with chert (Qp) and bioclastic fragments, including a bryozoan at the top.

Plate 4: Photomicrographs in both plane-polarized (PPL) and cross-polarized light (XPL). See Table 2 for petrographic descriptions. (A) Ph4 calcareous feldsarenite (EM15-38; DZ-6; PC-11) with monocrystalline quartz (Qm) and plagioclase feldspar (P) in a carbonate-rich matrix (Cal). (B) Ph4 volcanic-bearing conglomerate (EM15-39; CC-5) with plagioclase feldspar (P) and volcanic lithic fragments (Lv). (C) Ph4 volcaniclastic arenite (EM15-12) with highly-altered plagioclase feldspar (P). (D) Goler Gulch andesite (Pgg; EM15-01) with phenocrysts of plagioclase feldspar (P) in an opaque groundmass.

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Appendix D

LA-ICP-MS data for all concordant detrital zircon grains.

Grain Disc. Th/U Apparent ages (Ma) Interpreted age (Ma) 207Pb*/235U 206Pb*/238U 207Pb*/206Pb* Age 1σ Age 1σ Age 1σ Age 1σ 2σ

DZ-6 DZ-6-1 1.0% 1.49 254.1 3.2 251.5 3.1 294.4 47.3 251.3 3.4 6.8 DZ-6-2 0.4% 2.19 255.7 2.7 254.7 2.7 276.7 49.3 254.7 3.0 6.0 DZ-6-3 0.9% 2.14 257.4 3.0 255.1 2.7 297.5 49.1 254.9 3.0 6.0 DZ-6-4 0.3% 1.30 257.4 3.2 256.7 3.1 274.1 50.4 256.7 3.5 6.9 DZ-6-5 1.2% 1.76 259.7 2.7 256.7 2.7 300.6 47.5 256.5 3.0 6.0 DZ-6-6 0.7% 2.72 258.7 3.0 257.0 2.8 282.9 50.5 257.0 3.1 6.1 DZ-6-7 1.0% 1.44 259.8 2.9 257.2 3.0 293.1 46.9 257.0 3.3 6.5 DZ-6-8 0.5% 2.02 258.7 2.8 257.5 2.5 284.3 48.6 257.4 2.7 5.4 DZ-6-9 1.4% 1.32 261.9 2.5 258.3 2.2 301.0 46.9 258.1 2.4 4.8 DZ-6-10 0.8% 1.52 260.4 2.8 258.3 2.8 304.1 46.6 258.1 3.0 6.0 DZ-6-11 0.3% 2.04 259.4 2.6 258.6 2.5 283.4 48.0 258.5 2.8 5.6 DZ-6-12 0.1% 2.57 259.0 2.6 258.7 1.8 282.1 48.9 258.7 2.0 4.1 DZ-6-13 0.2% 2.58 259.4 3.5 258.8 3.2 266.9 50.7 258.4 3.6 7.2 DZ-6-14 1.1% 1.60 262.6 2.9 259.8 2.9 326.7 48.1 259.4 3.1 6.3 DZ-6-15 1.3% 1.30 263.3 2.9 260.0 2.6 314.6 46.7 259.7 2.9 5.7 DZ-6-16 0.4% 2.20 261.4 3.0 260.4 2.8 287.4 47.3 260.4 3.1 6.3 DZ-6-17 0.6% 2.40 262.2 2.7 260.5 2.5 283.4 47.4 260.5 2.8 5.6 DZ-6-18 0.3% 1.89 261.8 3.0 260.9 2.7 288.3 47.6 260.9 2.9 5.8 DZ-6-19 0.7% 1.69 262.7 3.5 260.9 3.2 292.7 47.2 260.8 3.5 6.9 DZ-6-20 0.6% 2.14 262.6 2.8 261.0 2.6 288.7 47.8 260.9 2.9 5.7 DZ-6-21 -0.2% 2.19 260.6 3.6 261.0 3.4 275.4 49.2 261.0 3.7 7.3 DZ-6-22 1.0% 2.19 263.6 3.5 261.0 3.0 299.7 48.0 260.9 3.3 6.7 DZ-6-23 0.7% 2.11 263.0 3.2 261.2 2.5 294.9 48.5 261.1 2.8 5.6 DZ-6-24 0.9% 1.72 263.7 3.3 261.2 3.4 305.4 47.9 261.0 3.7 7.5 DZ-6-25 0.0% 2.39 261.4 2.4 261.3 2.7 275.4 48.3 261.3 3.0 6.0 DZ-6-26 1.8% 2.79 266.6 3.7 261.9 2.8 302.3 50.6 261.8 3.1 6.1 DZ-6-27 1.5% 3.12 266.3 3.3 262.2 3.1 307.6 49.3 262.0 3.3 6.7 DZ-6-28 1.1% 1.61 265.2 2.6 262.4 2.2 305.9 47.5 262.2 2.4 4.8 DZ-6-29 1.3% 2.09 266.0 3.8 262.5 3.3 312.8 49.4 262.3 3.6 7.2 DZ-6-30 -0.5% 2.93 261.2 3.6 262.6 2.6 274.1 52.6 262.6 2.9 5.7 DZ-6-31 2.5% 2.38 269.4 3.4 262.6 2.5 328.9 49.9 262.2 2.8 5.6 DZ-6-32 0.6% 1.94 264.3 2.6 262.6 2.5 287.4 50.0 262.5 2.7 5.4 DZ-6-33 0.4% 2.71 263.7 3.4 262.7 2.2 270.0 50.1 262.7 2.4 4.8 DZ-6-34 1.1% 3.39 265.7 3.0 262.8 2.2 309.8 49.2 262.6 2.4 4.9 DZ-6-35 0.3% 1.67 263.8 2.9 263.1 3.0 298.8 47.3 263.0 3.3 6.7 DZ-6-36 0.6% 2.84 265.0 3.5 263.3 3.5 290.0 48.1 263.3 3.9 7.8 DZ-6-37 2.6% 2.47 270.3 4.0 263.3 3.1 349.9 53.0 262.8 3.5 6.9 DZ-6-38 4.2% 2.26 274.9 2.9 263.4 2.1 379.4 48.4 262.7 2.3 4.6 DZ-6-39 -0.5% 2.57 262.3 3.0 263.6 2.6 252.9 50.9 263.8 2.9 5.7 DZ-6-40 0.3% 2.94 264.7 2.9 263.8 2.8 293.1 50.5 263.7 3.1 6.3 DZ-6-41 1.0% 1.69 266.8 3.0 264.1 2.6 289.1 48.8 264.0 2.9 5.7 DZ-6-42 0.5% 1.42 265.5 2.4 264.2 2.1 280.3 47.2 264.2 2.2 4.5 DZ-6-43 -0.2% 2.00 263.9 3.0 264.3 2.8 282.1 47.9 264.3 3.1 6.1 DZ-6-44 0.4% 1.78 265.4 2.8 264.4 2.6 290.0 49.0 264.3 2.9 5.7 DZ-6-45 1.2% 2.42 267.9 3.7 264.7 3.2 308.0 51.9 264.5 3.5 6.9 DZ-6-46 0.2% 1.48 265.4 2.3 264.8 2.3 291.8 46.6 264.7 2.4 4.9 DZ-6-47 0.7% 3.04 266.9 3.1 264.9 2.6 297.5 49.4 264.8 2.9 5.7 DZ-6-48 -0.2% 3.13 264.6 2.8 265.0 2.4 275.8 50.4 265.0 2.6 5.2 DZ-6-49 1.5% 2.22 269.1 3.4 265.1 2.2 305.9 49.5 265.0 2.4 4.9 DZ-6-50 0.3% 1.91 266.1 2.6 265.3 2.3 278.5 50.2 265.3 2.6 5.2 DZ-6-51 0.2% 1.30 265.8 2.4 265.3 2.5 289.1 47.5 265.2 2.8 5.6 DZ-6-52 0.9% 6.96 267.8 3.2 265.4 3.2 297.1 47.6 265.3 3.5 7.1 DZ-6-53 2.9% 2.75 273.3 3.5 265.5 2.5 361.7 52.2 264.9 2.8 5.6 DZ-6-54 1.7% 2.41 270.1 3.9 265.6 2.8 326.3 53.6 265.3 3.0 6.0

115

Grain Disc. Th/U Apparent ages (Ma) Interpreted age (Ma) 207Pb*/235U 206Pb*/238U 207Pb*/206Pb* Age 1σ Age 1σ Age 1σ Age 1σ 2σ DZ-6-55 0.0% 2.89 265.6 2.9 265.7 2.6 278.5 49.6 265.7 2.9 5.8 DZ-6-56 0.9% 2.63 268.3 3.7 265.8 3.6 305.0 48.7 265.7 3.9 7.9 DZ-6-57 0.2% 2.47 266.7 2.9 266.1 2.5 308.5 50.0 266.0 2.8 5.6 DZ-6-58 0.2% 2.04 266.8 2.4 266.3 2.6 290.5 47.3 266.3 2.9 5.7 DZ-6-59 0.4% 1.47 267.5 2.4 266.3 2.1 293.1 47.1 266.3 2.3 4.6 DZ-6-60 0.9% 1.98 269.2 3.7 266.7 3.3 305.4 49.0 266.6 3.6 7.2 DZ-6-61 2.7% 1.99 274.1 3.1 266.8 2.4 348.2 48.8 266.3 2.7 5.4 DZ-6-62 0.3% 1.68 267.6 2.8 266.8 2.4 293.1 48.5 266.8 2.7 5.3 DZ-6-63 3.1% 1.92 275.3 5.0 266.9 2.6 356.2 55.7 266.4 2.9 5.7 DZ-6-64 1.6% 2.20 271.4 2.7 267.0 2.4 321.5 48.0 266.7 2.6 5.2 DZ-6-65 -1.8% 2.73 262.3 3.4 267.1 3.0 236.6 51.9 267.5 3.3 6.7 DZ-6-66 0.3% 2.31 267.9 3.2 267.2 2.9 288.3 48.9 267.2 3.3 6.5 DZ-6-67 0.0% 2.48 267.3 3.1 267.2 2.5 289.6 48.1 267.2 2.8 5.6 DZ-6-68 0.2% 2.35 267.8 2.7 267.2 2.5 289.6 48.7 267.2 2.8 5.6 DZ-6-69 0.4% 1.31 268.3 2.6 267.3 2.3 286.9 46.7 267.3 2.6 5.2 DZ-6-70 0.3% 1.62 268.3 2.4 267.4 2.5 295.8 47.2 267.3 2.8 5.6 DZ-6-71 -0.2% 2.37 267.0 2.6 267.5 2.5 289.1 47.8 267.5 2.7 5.4 DZ-6-72 1.4% 1.33 271.5 2.0 267.8 2.1 318.5 46.4 267.5 2.3 4.6 DZ-6-73 -0.2% 2.27 267.3 3.0 267.8 2.5 291.8 48.8 267.8 2.8 5.6 DZ-6-74 -0.7% 2.33 265.9 2.7 267.8 2.4 268.7 50.3 267.9 2.7 5.3 DZ-6-75 0.6% 2.79 269.4 3.2 267.9 2.9 293.1 47.5 267.8 3.2 6.4 DZ-6-76 0.6% 2.56 269.5 2.8 268.0 2.3 287.4 49.3 268.0 2.6 5.2 DZ-6-77 1.1% 1.87 271.0 3.1 268.1 2.9 317.6 48.2 267.9 3.3 6.5 DZ-6-78 0.4% 3.08 269.2 4.0 268.1 3.1 287.4 53.8 268.1 3.5 6.9 DZ-6-79 -0.8% 2.34 266.6 2.9 268.6 3.1 264.7 49.0 268.8 3.5 6.9 DZ-6-80 0.2% 1.94 269.3 2.9 268.8 2.8 297.5 48.3 268.7 3.1 6.1 DZ-6-81 0.4% 1.56 270.0 2.6 268.8 2.7 297.5 48.0 268.7 3.0 6.0 DZ-6-82 0.8% 1.34 270.9 3.2 268.8 3.3 310.2 46.5 268.7 3.7 7.3 DZ-6-83 0.4% 2.34 270.0 2.9 268.9 2.5 298.4 50.5 268.8 2.8 5.6 DZ-6-84 1.5% 3.00 273.2 3.3 269.0 3.1 316.3 48.1 268.8 3.4 6.8 DZ-6-85 0.9% 1.69 271.4 3.1 269.0 3.0 301.0 48.3 268.9 3.3 6.7 DZ-6-86 0.2% 2.57 269.9 3.1 269.3 2.7 290.0 49.0 269.3 3.0 6.0 DZ-6-87 0.1% 3.02 269.6 3.0 269.3 2.1 285.2 49.9 269.3 2.3 4.6 DZ-6-88 0.8% 2.47 271.7 2.9 269.5 2.1 301.5 50.4 269.4 2.2 4.5 DZ-6-89 1.0% 2.35 272.3 3.8 269.6 2.6 304.5 54.0 269.5 2.9 5.7 DZ-6-90 -0.1% 2.38 269.6 3.6 269.8 2.9 286.5 49.4 269.8 3.2 6.4 DZ-6-91 -0.1% 2.68 269.6 2.9 269.8 2.8 278.1 48.8 269.9 3.1 6.3 DZ-6-92 0.5% 2.70 271.3 3.6 269.9 2.8 298.4 51.0 269.8 3.1 6.3 DZ-6-93 1.6% 1.70 274.5 2.1 270.1 1.8 322.8 47.6 269.8 2.0 3.9 DZ-6-94 0.0% 2.36 270.7 2.9 270.7 2.9 292.7 47.5 270.7 3.1 6.3 DZ-6-95 0.6% 1.05 272.4 2.3 270.8 2.4 297.5 46.3 270.8 2.6 5.2 DZ-6-96 0.4% 2.78 272.2 3.3 271.0 2.7 314.1 49.5 270.8 3.0 6.0 DZ-6-97 -0.6% 2.00 269.5 3.1 271.0 3.0 281.6 48.9 271.1 3.3 6.5 DZ-6-98 -0.1% 1.64 270.9 2.9 271.3 2.4 293.1 49.4 271.3 2.7 5.3 DZ-6-99 1.8% 2.08 276.2 3.4 271.3 2.7 341.3 49.4 270.9 3.0 6.0 DZ-6-100 0.1% 1.54 271.7 2.4 271.5 2.0 278.5 47.3 271.5 2.2 4.5 DZ-6-101 0.0% 2.35 271.9 2.6 272.0 2.2 289.1 48.0 272.0 2.4 4.8 DZ-6-102 -1.6% 2.58 268.0 3.0 272.3 3.1 253.9 52.3 272.6 3.4 6.8 DZ-6-103 0.8% 2.58 274.9 3.6 272.8 3.1 305.9 50.0 272.6 3.4 6.8 DZ-6-104 0.4% 2.43 274.5 2.3 273.3 2.3 301.9 47.0 273.2 2.5 5.0 DZ-6-105 0.0% 1.77 273.7 2.3 273.8 2.4 291.4 47.3 273.8 2.7 5.4 DZ-6-106 0.5% 2.44 275.3 3.3 274.0 2.5 294.4 50.3 274.0 2.7 5.4 DZ-6-107 -0.6% 2.03 273.1 2.4 274.8 2.6 278.9 47.1 274.8 2.9 5.7 DZ-6-108 -0.1% 1.22 274.5 2.6 274.9 2.6 282.5 46.9 275.1 2.9 5.8 DZ-6-109 0.1% 2.95 275.5 3.3 275.3 2.7 309.3 49.9 275.2 3.0 6.0 DZ-6-110 0.5% 2.15 277.4 3.2 276.1 2.8 304.1 49.5 276.1 3.1 6.3 DZ-6-111 -0.4% 1.78 275.4 3.4 276.4 3.6 283.8 47.9 276.5 3.9 7.9 DZ-6-112 0.3% 1.30 277.4 2.6 276.6 2.2 295.3 46.7 276.6 2.4 4.9 DZ-6-113 -0.6% 2.46 275.2 2.8 276.8 2.4 297.5 50.3 276.8 2.6 5.2 DZ-6-114 0.0% 2.31 277.5 3.3 277.5 2.9 293.6 49.8 277.5 3.2 6.4 DZ-6-115 0.9% 2.58 283.2 2.6 280.7 2.2 303.2 48.0 280.6 2.4 4.8 DZ-6-116 -1.0% 2.66 278.3 3.6 281.2 2.7 303.2 52.6 281.2 3.0 6.0 DZ-6-117 0.4% 3.21 283.8 3.6 282.7 3.0 299.7 49.7 282.8 3.3 6.5 116

Grain Disc. Th/U Apparent ages (Ma) Interpreted age (Ma) 207Pb*/235U 206Pb*/238U 207Pb*/206Pb* Age 1σ Age 1σ Age 1σ Age 1σ 2σ DZ-6-118 -0.2% 1.62 282.2 2.9 282.9 2.1 306.7 49.3 282.8 2.4 4.8 DZ-6-119 -0.5% 2.20 284.3 3.3 285.6 2.7 293.1 49.0 285.7 2.9 5.8 DZ-6-120 0.0% 2.07 291.3 4.0 291.2 4.5 302.3 49.7 291.3 4.9 9.8 DZ-6-121 1.0% 1.10 336.6 4.8 333.2 4.4 378.1 49.6 333.0 4.8 9.7

DZ-5 DZ-5-1 3.7% 1.21 246.1 2.8 237.1 2.0 346.4 48.5 236.5 2.2 4.4 DZ-5-2 0.3% 1.88 256.4 2.4 255.7 2.3 276.7 47.7 255.7 2.5 5.0 DZ-5-3 0.1% 1.78 256.2 2.3 256.0 2.2 282.5 47.1 255.9 2.4 4.8 DZ-5-4 4.6% 2.46 270.4 3.6 257.9 2.7 396.4 53.1 256.6 2.9 5.8 DZ-5-5 -0.3% 2.03 256.8 2.9 257.5 2.6 273.2 49.9 257.2 2.9 5.8 DZ-5-6 1.4% 1.43 261.3 3.2 257.6 3.7 319.8 46.6 257.3 4.0 8.0 DZ-5-7 0.5% 1.76 258.7 2.4 257.4 2.4 289.1 48.2 257.3 2.6 5.2 DZ-5-8 -0.1% 1.84 257.7 3.2 258.0 3.1 279.8 48.3 258.0 3.3 6.7 DZ-5-9 1.5% 1.54 262.2 3.1 258.3 2.6 299.3 50.3 258.1 2.9 5.7 DZ-5-10 0.0% 1.98 259.1 2.8 259.2 2.2 280.7 51.7 259.2 2.4 4.8 DZ-5-11 1.1% 1.46 262.3 2.4 259.5 2.3 299.7 47.9 259.4 2.5 5.0 DZ-5-12 0.8% 1.22 261.8 3.8 259.8 3.1 294.4 54.1 259.6 3.4 6.8 DZ-5-13 -0.5% 1.32 258.4 2.9 259.7 2.4 262.0 50.7 259.8 2.6 5.2 DZ-5-14 -0.3% 1.71 259.2 3.0 260.0 2.6 274.1 48.9 260.0 2.9 5.7 DZ-5-15 -1.0% 2.50 259.0 2.6 261.5 2.1 268.7 49.6 261.6 2.4 4.8 DZ-5-16 0.2% 2.49 262.4 2.9 262.0 2.3 284.3 49.4 262.0 2.6 5.2 DZ-5-17 0.3% 2.31 263.8 2.6 263.1 2.9 294.9 49.4 262.6 3.1 6.1 DZ-5-18 1.1% 2.37 266.1 4.0 263.1 3.0 340.9 51.2 262.7 3.3 6.7 DZ-5-19 0.8% 2.31 264.9 3.6 262.8 3.3 294.0 48.3 262.8 3.7 7.3 DZ-5-20 0.3% 1.39 264.0 3.2 263.1 3.3 290.9 48.0 263.1 3.6 7.2 DZ-5-21 0.4% 1.87 264.3 3.5 263.2 3.3 290.5 47.6 263.2 3.6 7.2 DZ-5-22 0.3% 1.05 265.3 2.6 264.4 2.1 292.2 47.7 264.3 2.2 4.5 DZ-5-23 -0.3% 1.76 263.7 2.2 264.4 1.9 288.7 47.6 264.4 2.0 4.1 DZ-5-24 0.9% 2.70 266.8 2.9 264.4 3.0 291.4 48.2 264.4 3.3 6.5 DZ-5-25 2.4% 1.95 271.4 3.5 265.0 2.3 334.0 52.2 264.6 2.6 5.2 DZ-5-26 4.5% 1.21 278.6 5.1 266.1 3.6 412.5 55.7 265.2 4.0 8.0 DZ-5-27 -1.2% 2.36 262.2 2.6 265.3 2.2 269.1 49.1 265.4 2.4 4.9 DZ-5-28 0.1% 1.83 266.0 3.2 265.7 3.1 295.8 48.2 265.6 3.4 6.8 DZ-5-29 0.2% 1.50 266.3 2.7 265.7 2.1 285.2 49.5 265.7 2.2 4.5 DZ-5-30 -0.2% 1.34 265.1 2.7 265.7 2.7 272.3 48.3 265.8 2.9 5.8 DZ-5-31 2.9% 1.52 275.2 3.6 267.2 3.6 348.6 45.8 266.8 3.9 7.9 DZ-5-32 0.5% 1.26 269.8 2.4 268.4 2.0 288.7 48.4 268.4 2.2 4.4 DZ-5-33 -0.3% 2.46 267.6 3.1 268.3 2.8 278.9 49.8 268.4 3.1 6.3 DZ-5-34 2.5% 1.83 276.0 2.9 269.1 2.1 355.4 51.2 268.6 2.3 4.6 DZ-5-35 0.1% 2.02 272.2 3.2 272.0 2.8 295.8 48.9 272.0 3.1 6.1 DZ-5-36 0.6% 1.08 274.5 3.4 272.8 3.1 301.9 47.7 272.7 3.5 6.9 DZ-5-37 -0.2% 2.84 273.8 3.4 274.4 2.5 311.5 50.1 274.3 2.8 5.6 DZ-5-38 0.1% 1.67 275.1 3.4 274.9 2.9 297.1 48.0 274.9 3.2 6.4 DZ-5-39 0.1% 2.15 275.1 2.8 274.9 2.6 292.7 49.0 274.9 2.9 5.7 DZ-5-40 2.1% 1.88 282.0 2.5 276.0 3.0 358.8 47.5 275.5 3.3 6.7 DZ-5-41 0.4% 1.70 277.4 2.9 276.2 2.8 305.4 47.7 276.1 3.1 6.3 DZ-5-42 -0.2% 1.82 276.4 3.5 276.9 3.0 281.6 48.5 277.0 3.3 6.7 DZ-5-43 3.2% 1.61 1788.6 8.7 1768.0 16.0 1825.9 37.0 1825.9 37.0 74.1 DZ-5-44 -0.9% 0.83 2113.0 11.0 2127.0 23.0 2108.2 35.6 2108.2 35.6 71.3

DZ-4 DZ-4-1 2.6% 2.43 265.0 15.0 258.0 13.0 480.0 110.0 255.9 14.0 28.1 DZ-4-2 -2.2% 1.25 251.0 16.0 256.5 9.6 250.0 120.0 256.6 10.2 20.3 DZ-4-3 -0.5% 2.35 261.0 12.0 262.4 9.9 270.0 120.0 262.7 10.9 21.7 DZ-4-4 -2.9% 3.84 262.0 14.0 269.6 7.5 280.0 110.0 269.5 8.1 16.3 DZ-4-5 -1.1% 2.98 272.0 13.0 275.1 8.0 430.0 110.0 273.7 8.8 17.6 DZ-4-6 -4.2% 2.21 264.0 15.0 275.0 10.0 220.0 110.0 274.9 10.9 21.7 DZ-4-7 2.5% 4.48 284.0 15.0 276.8 8.4 320.0 110.0 276.4 9.5 19.0 DZ-4-8 -1.8% 3.46 271.0 17.0 276.0 18.0 250.0 120.0 276.5 19.7 39.3 DZ-4-9 3.5% 2.51 289.0 14.0 279.0 14.0 350.0 100.0 278.6 15.6 31.2 DZ-4-10 2.1% 3.81 287.0 17.0 281.0 16.0 360.0 110.0 279.9 17.0 33.9

117

Grain Disc. Th/U Apparent ages (Ma) Interpreted age (Ma) 207 235 206 238 207 206 Pb*/ U Pb*/ U Pb*/ Pb* Age 1σ Age 1σ Age 1σ Age 1σ 2σ DZ-4-11 -0.4% 2.75 280.0 16.0 281.0 12.0 380.0 120.0 280.2 12.9 25.8 DZ-4-12 7.6% 7.54 304.0 29.0 281.0 20.0 350.0 200.0 280.5 21.7 43.4 DZ-4-13 -4.9% 3.56 267.0 13.0 280.0 11.0 160.0 100.0 280.9 12.2 24.3 DZ-4-14 -1.8% 1.83 276.0 12.0 281.0 11.0 284.0 96.0 281.2 12.9 25.8 DZ-4-15 -0.7% 4.26 283.0 13.0 285.0 10.0 430.0 110.0 283.5 11.5 23.1 DZ-4-16 3.4% 1.87 294.0 18.0 284.0 12.0 350.0 130.0 284.0 13.6 27.1 DZ-4-17 -4.0% 4.97 274.0 16.0 285.0 11.0 150.0 110.0 286.0 12.2 24.4 DZ-4-18 11.1% 9.50 324.0 23.0 288.0 17.0 450.0 140.0 286.3 19.0 38.0 DZ-4-19 2.4% 3.04 294.0 22.0 287.0 12.0 320.0 140.0 286.8 13.5 27.1 DZ-4-20 2.0% 5.29 293.0 15.0 287.0 14.0 335.0 90.0 287.0 15.6 31.2 DZ-4-21 6.5% 10.64 308.0 19.0 288.0 14.0 380.0 140.0 287.1 15.6 31.2 DZ-4-22 -9.2% 2.30 262.0 14.0 286.0 11.0 166.0 96.0 287.2 12.9 25.7 DZ-4-23 -4.7% 3.30 274.0 12.0 286.9 8.9 221.0 93.0 287.4 9.5 19.0 DZ-4-24 1.4% 2.29 292.0 20.0 288.0 15.0 310.0 120.0 287.9 17.0 33.9 DZ-4-25 1.4% 4.65 293.0 19.0 289.0 14.0 300.0 130.0 288.2 14.9 29.8 DZ-4-26 2.8% 6.38 299.0 13.0 290.6 8.9 330.0 100.0 290.0 9.5 19.0 DZ-4-27 -0.3% 2.53 290.0 10.0 291.0 12.0 261.0 89.0 290.6 12.9 25.8 DZ-4-28 -2.2% 2.20 284.0 12.0 290.3 8.6 260.0 100.0 290.7 9.5 19.0 DZ-4-29 -3.5% 5.16 282.0 15.0 292.0 15.0 240.0 110.0 292.1 16.3 32.6 DZ-4-30 3.6% 5.37 304.0 20.0 293.0 16.0 370.0 140.0 292.2 17.6 35.3 DZ-4-31 -1.2% 3.18 290.0 15.0 293.4 9.5 380.0 88.0 293.1 10.2 20.3 DZ-4-32 -1.7% 4.83 289.0 14.0 294.0 11.0 250.0 91.0 294.4 12.9 25.8 DZ-4-33 -6.5% 3.16 276.0 17.0 294.0 16.0 231.0 93.0 294.6 17.6 35.3 DZ-4-34 0.3% 4.48 295.0 20.0 294.0 14.0 240.0 120.0 294.8 15.6 31.2 DZ-4-35 1.3% 4.82 300.0 20.0 296.0 17.0 330.0 140.0 295.7 19.0 38.0 DZ-4-36 2.6% 2.41 306.0 19.0 298.0 15.0 520.0 140.0 295.8 16.9 33.9 DZ-4-37 -1.4% 3.09 292.0 14.0 296.0 14.0 270.0 89.0 296.2 15.6 31.2 DZ-4-38 -0.3% 2.50 298.0 17.0 299.0 14.0 260.0 120.0 299.3 14.9 29.9 DZ-4-39 -0.3% 6.32 298.0 19.0 299.0 17.0 303.0 99.0 299.7 19.0 38.0 DZ-4-40 -3.1% 3.40 291.0 15.0 300.0 14.0 240.0 110.0 300.0 15.6 31.2 DZ-4-41 2.0% 6.77 307.0 24.0 301.0 24.0 410.0 170.0 300.5 26.4 52.9 DZ-4-42 4.7% 3.84 316.0 17.0 301.0 18.0 370.0 120.0 301.2 19.6 39.2 DZ-4-43 -2.7% 6.10 299.0 17.0 307.0 15.0 210.0 110.0 307.9 17.0 33.9 DZ-4-44 -2.7% 5.45 299.0 21.0 307.0 13.0 240.0 130.0 308.2 14.9 29.9 DZ-4-45 -3.0% 3.67 300.0 16.0 309.0 14.0 242.0 97.0 309.5 14.9 29.8 DZ-4-46 -1.0% 8.09 306.0 23.0 309.0 21.0 310.0 160.0 309.7 23.1 46.1 DZ-4-47 1.3% 5.56 313.0 32.0 309.0 25.0 200.0 240.0 309.8 27.1 54.1 DZ-4-48 -0.3% 5.39 309.0 16.0 310.0 14.0 260.0 120.0 310.5 16.2 32.4 DZ-4-49 -1.3% 4.21 306.0 17.0 310.0 16.0 210.0 100.0 311.4 17.6 35.3 DZ-4-50 -1.0% 5.81 308.0 28.0 311.0 18.0 200.0 190.0 312.2 20.4 40.7 DZ-4-51 9.0% 14.50 345.0 24.0 314.0 16.0 400.0 150.0 313.0 17.6 35.2 DZ-4-52 -1.0% 2.76 311.0 17.0 314.0 15.0 330.0 130.0 313.6 16.3 32.5 DZ-4-53 3.1% 9.81 324.0 26.0 314.0 16.0 290.0 170.0 314.4 17.6 35.3 DZ-4-54 0.9% 6.34 316.0 25.0 313.0 20.0 260.0 150.0 314.7 21.7 43.3 DZ-4-55 -7.9% 5.36 291.0 18.0 314.0 12.0 150.0 130.0 315.2 12.9 25.8 DZ-4-56 -3.6% 6.34 305.0 24.0 316.0 21.0 220.0 140.0 316.9 23.7 47.4 DZ-4-57 2.7% 4.40 330.0 25.0 321.0 24.0 320.0 140.0 322.4 27.0 54.1 DZ-4-58 2.4% 20.30 333.0 21.0 325.0 15.0 320.0 120.0 324.8 16.9 33.9 DZ-4-59 -6.6% 5.51 304.0 27.0 324.0 18.0 240.0 200.0 325.9 19.7 39.3 DZ-4-60 -1.9% 2.06 322.0 17.0 328.0 18.0 500.0 100.0 326.1 19.6 39.2 DZ-4-61 -6.6% 8.14 304.0 20.0 324.0 19.0 100.0 130.0 326.2 21.0 42.0 DZ-4-62 3.5% 4.19 345.0 17.0 333.0 15.0 340.0 100.0 333.4 16.9 33.9 DZ-4-63 -2.5% 9.70 325.0 20.0 333.0 18.0 220.0 110.0 334.0 19.7 39.3 DZ-4-64 0.3% 5.41 338.0 23.0 337.0 16.0 270.0 120.0 337.9 17.6 35.3 DZ-4-65 10.2% 7.63 452.0 31.0 406.0 27.0 580.0 170.0 404.6 30.5 61.0 DZ-4-66 11.3% 9.96 486.0 31.0 431.0 36.0 640.0 130.0 429.7 40.5 81.1 DZ-4-67 3.6% 3.55 478.0 24.0 461.0 24.0 754.0 99.0 456.2 26.6 53.2 DZ-4-68 3.4% 2.30 495.0 23.0 478.0 16.0 650.0 110.0 475.4 18.3 36.6 DZ-4-69 1.0% 2.19 586.0 33.0 580.0 31.0 790.0 110.0 575.7 35.9 71.8 DZ-4-70 -1.4% 1.88 586.0 27.0 594.0 24.0 660.0 100.0 592.1 27.8 55.5 DZ-4-71 -2.6% 1.45 588.0 18.0 603.0 25.0 527.0 75.0 605.1 29.2 58.3 DZ-4-72 4.6% 2.19 722.0 33.0 689.0 36.0 830.0 130.0 685.3 42.7 85.4

118

Grain Disc. Th/U Apparent ages (Ma) Interpreted age (Ma) 207 235 206 238 207 206 Pb*/ U Pb*/ U Pb*/ Pb* Age 1σ Age 1σ Age 1σ Age 1σ 2σ DZ-4-73 0.6% 1.92 697.0 32.0 693.0 28.0 815.0 92.0 686.7 31.1 62.3 DZ-4-74 14.8% 6.01 826.0 28.0 704.0 27.0 1171.0 67.0 690.8 31.8 63.7 DZ-4-75 -1.1% 2.65 707.0 23.0 715.0 28.0 673.0 92.0 717.0 33.2 66.4 DZ-4-76 -4.9% 0.83 775.0 48.0 813.0 32.0 730.0 200.0 814.1 38.5 77.1 DZ-4-77 21.4% 5.49 1240.0 46.0 975.0 61.0 1648.0 72.0 943.5 74.0 148.1 DZ-4-78 1.1% 2.24 1080.0 40.0 1011.0 36.0 1022.0 94.0 1022.0 94.0 188.0 DZ-4-79 1.0% 2.08 1027.0 38.0 1017.0 35.0 810.0 110.0 1027.8 43.3 86.7 DZ-4-80 4.0% 3.35 1130.0 45.0 1085.0 30.0 984.0 89.0 1089.8 37.9 75.9 DZ-4-81 7.6% 2.09 1572.0 41.0 1540.0 65.0 1666.0 65.0 1666.0 65.0 130.0 DZ-4-82 -5.8% 1.64 1775.0 36.0 1827.0 44.0 1727.0 55.0 1727.0 55.0 110.0 DZ-4-83 -3.6% 7.56 1802.0 42.0 1820.0 76.0 1757.0 68.0 1757.0 68.0 136.0 DZ-4-84 15.5% 2.27 1614.0 27.0 1496.0 43.0 1770.0 57.0 1770.0 57.0 114.0 DZ-4-85 11.2% 6.03 1697.0 81.0 1580.0 130.0 1780.0 120.0 1780.0 120.0 240.0 DZ-4-86 -1.0% 1.00 1771.0 48.0 1803.0 72.0 1786.0 68.0 1786.0 68.0 136.0 DZ-4-87 -2.8% 0.79 1840.0 38.0 1856.0 54.0 1806.0 53.0 1806.0 53.0 106.0 DZ-4-88 -5.1% 1.48 1851.0 37.0 1909.0 68.0 1817.0 67.0 1817.0 67.0 134.0 DZ-4-89 4.7% 2.03 1706.0 54.0 1739.0 82.0 1824.0 81.0 1824.0 81.0 162.0 DZ-4-90 0.8% 1.37 1835.0 61.0 1822.0 84.0 1836.0 94.0 1836.0 94.0 188.0 DZ-4-91 -7.5% 2.30 1912.0 50.0 1998.0 68.0 1859.0 69.0 1859.0 69.0 138.0 DZ-4-92 -9.6% 3.61 1990.0 84.0 2060.0 110.0 1880.0 150.0 1880.0 150.0 300.0 DZ-4-93 -2.2% 6.28 1952.0 51.0 1989.0 57.0 1946.0 74.0 1946.0 74.0 148.0 DZ-4-94 -3.1% 3.08 1970.0 62.0 2010.0 140.0 1950.0 130.0 1950.0 130.0 260.0 DZ-4-95 0.9% 7.01 1949.0 60.0 1940.0 130.0 1957.0 72.0 1957.0 72.0 144.0 DZ-4-96 -4.6% 1.18 2008.0 52.0 2050.0 95.0 1959.0 69.0 1959.0 69.0 138.0 DZ-4-97 -0.4% 1.35 2010.0 64.0 1997.0 99.0 1990.0 100.0 1990.0 100.0 200.0 DZ-4-98 -9.9% 1.73 2133.0 65.0 2230.0 110.0 2030.0 92.0 2030.0 92.0 184.0 DZ-4-99 -1.1% 0.94 2134.0 40.0 2100.0 100.0 2078.0 65.0 2078.0 65.0 130.0 DZ-4-100 -8.0% 3.80 2287.0 61.0 2370.0 150.0 2194.0 72.0 2194.0 72.0 144.0 DZ-4-101 13.0% 2.06 2155.0 50.0 1995.0 79.0 2292.0 53.0 2292.0 53.0 106.0 DZ-4-102 0.8% 1.23 2367.0 53.0 2470.0 78.0 2490.0 66.0 2490.0 66.0 132.0 DZ-4-103 9.6% 0.94 2402.0 39.0 2291.0 73.0 2534.0 61.0 2534.0 61.0 122.0 DZ-4-104 12.2% 3.31 2360.0 110.0 2230.0 180.0 2540.0 120.0 2540.0 120.0 240.0 DZ-4-105 -3.1% 3.04 2551.0 56.0 2640.0 120.0 2560.0 79.0 2560.0 79.0 158.0 DZ-4-106 -7.6% 12.57 2715.0 58.0 2800.0 120.0 2602.0 63.0 2602.0 63.0 126.0 DZ-4-107 10.3% 2.79 2492.0 67.0 2370.0 140.0 2643.0 76.0 2643.0 76.0 152.0 DZ-4-108 3.8% 1.66 2580.0 46.0 2553.0 96.0 2655.0 67.0 2655.0 67.0 134.0 DZ-4-109 -6.4% 2.40 2763.0 46.0 2880.0 110.0 2707.0 55.0 2707.0 55.0 110.0 DZ-4-110 3.2% 2.40 2745.0 50.0 2740.0 130.0 2832.0 66.0 2832.0 66.0 132.0

DZ-3 DZ-3-1 4.1% 2.51 268.0 16.0 257.0 9.3 450.0 110.0 255.6 10.1 20.2 DZ-3-2 11.1% 1.62 292.0 19.0 259.7 7.8 600.0 110.0 256.6 8.8 17.6 DZ-3-3 10.3% 1.92 290.0 14.0 260.0 15.0 550.0 110.0 257.2 16.3 32.6 DZ-3-4 16.6% 2.54 316.0 14.0 263.6 7.8 760.0 120.0 259.4 8.8 17.6 DZ-3-5 0.8% 3.67 262.0 12.0 260.0 11.0 260.0 100.0 260.2 11.5 23.0 DZ-3-6 -1.2% 3.79 258.0 13.0 261.0 10.0 214.0 97.0 261.3 11.5 23.1 DZ-3-7 5.7% 1.94 279.0 15.0 263.0 11.0 285.0 89.0 263.1 11.5 23.1 DZ-3-8 -1.9% 2.67 260.0 16.0 265.0 10.0 180.0 110.0 264.5 11.5 23.1 DZ-3-9 -1.0% 2.71 263.0 13.0 265.7 8.8 280.0 87.0 265.7 9.5 19.0 DZ-3-10 -5.3% 4.04 256.0 10.0 269.6 8.4 264.0 87.0 269.4 9.5 19.0 DZ-3-11 6.8% 1.92 292.0 25.0 272.0 22.0 500.0 180.0 270.2 24.4 48.9 DZ-3-12 4.2% 2.44 284.0 17.0 272.0 14.0 310.0 120.0 271.4 15.6 31.1 DZ-3-13 8.4% 1.63 299.0 15.0 274.0 13.0 510.0 91.0 271.7 14.2 28.5 DZ-3-14 3.8% 2.91 287.0 21.0 276.0 13.0 280.0 130.0 275.6 14.3 28.5 DZ-3-15 1.2% 2.98 280.0 12.0 276.6 8.5 295.0 89.0 276.1 9.5 19.0 DZ-3-16 0.0% 3.62 276.0 13.0 276.0 10.0 231.0 97.0 276.7 10.9 21.7 DZ-3-17 -1.8% 2.94 272.0 12.0 277.0 11.0 284.0 98.0 276.8 12.2 24.4 DZ-3-18 5.4% 2.30 295.0 14.0 279.0 11.0 430.0 110.0 278.0 11.5 23.1 DZ-3-19 1.4% 2.31 283.0 12.0 279.0 13.0 393.0 94.0 278.5 14.2 28.5 DZ-3-20 2.1% 2.91 286.0 15.0 280.0 10.0 287.0 90.0 280.0 10.9 21.7 DZ-3-21 0.7% 3.18 283.0 16.0 281.0 11.0 230.0 120.0 280.8 12.2 24.4 DZ-3-22 -1.4% 2.04 277.0 14.0 281.0 11.0 250.0 100.0 281.5 12.2 24.4

119

Grain Disc. Th/U Apparent ages (Ma) Interpreted age (Ma) 207 235 206 238 207 206 Pb*/ U Pb*/ U Pb*/ Pb* Age 1σ Age 1σ Age 1σ Age 1σ 2σ DZ-3-23 -9.7% 3.14 258.0 11.0 283.0 11.0 92.0 96.0 283.5 12.2 24.4 DZ-3-24 -3.7% 2.88 273.0 14.0 283.0 13.0 221.0 88.0 283.5 14.3 28.5 DZ-3-25 5.6% 3.39 302.0 17.0 285.0 13.0 320.0 110.0 284.5 14.3 28.5 DZ-3-26 -1.4% 3.00 285.0 16.0 289.0 12.0 310.0 110.0 288.4 12.9 25.8 DZ-3-27 1.7% 3.26 295.0 15.0 290.0 10.0 292.0 87.0 289.6 10.9 21.7 DZ-3-28 0.7% 2.21 293.0 13.0 291.0 13.0 309.0 72.0 290.9 14.3 28.5 DZ-3-29 2.0% 2.30 299.0 16.0 293.0 11.0 310.0 120.0 292.5 12.2 24.5 DZ-3-30 -1.4% 8.82 289.0 13.0 293.0 15.0 264.0 77.0 293.8 16.3 32.5 DZ-3-31 -5.4% 4.32 280.0 16.0 295.0 16.0 290.0 120.0 294.8 17.0 34.0 DZ-3-32 -7.2% 2.64 277.7 9.5 297.6 9.9 194.0 80.0 298.7 10.9 21.7 DZ-3-33 2.3% 3.50 307.0 15.0 300.0 14.0 312.0 80.0 299.5 14.9 29.9 DZ-3-34 -1.0% 3.49 296.0 15.0 299.0 15.0 234.0 85.0 299.6 16.3 32.6 DZ-3-35 -1.3% 2.68 297.0 13.0 301.0 15.0 230.0 110.0 301.5 16.3 32.6 DZ-3-36 1.9% 5.40 309.0 16.0 303.0 15.0 356.0 99.0 303.1 17.0 33.9 DZ-3-37 2.3% 16.01 311.0 15.0 304.0 14.0 345.0 75.0 304.2 15.6 31.2 DZ-3-38 -1.7% 5.18 298.0 14.0 303.0 17.0 188.0 71.0 304.5 19.0 38.0 DZ-3-39 -2.4% 3.11 296.0 11.0 303.0 13.0 144.0 82.0 304.7 14.3 28.5 DZ-3-40 7.3% 3.37 331.0 19.0 307.0 17.0 450.0 110.0 305.7 18.3 36.7 DZ-3-41 2.2% 1.94 314.0 21.0 307.0 16.0 390.0 110.0 306.3 17.0 33.9 DZ-3-42 2.8% 1.49 316.0 17.0 307.0 16.0 362.0 97.0 306.5 17.6 35.3 DZ-3-43 -2.0% 2.10 301.0 18.0 307.0 19.0 329.0 90.0 306.8 21.0 42.1 DZ-3-44 0.0% 3.70 309.0 13.0 309.0 16.0 241.0 96.0 309.5 17.0 33.9 DZ-3-45 6.3% 0.97 333.0 17.0 312.0 20.0 542.0 84.0 310.6 22.4 44.8 DZ-3-46 -4.0% 7.22 299.0 16.0 311.0 19.0 192.0 90.0 312.6 21.7 43.4 DZ-3-47 1.6% 3.90 318.0 12.0 313.0 14.0 364.0 86.0 312.8 15.6 31.2 DZ-3-48 28.5% 4.36 445.0 21.0 318.0 11.0 284.0 92.0 317.8 12.2 24.4 DZ-3-49 10.6% 1.69 359.0 20.0 321.0 16.0 520.0 120.0 318.7 17.6 35.3 DZ-3-50 -2.5% 8.92 316.0 16.0 324.0 16.0 182.0 71.0 325.1 18.3 36.6 DZ-3-51 -4.8% 2.06 310.0 14.0 325.0 19.0 204.0 71.0 326.1 21.1 42.1 DZ-3-52 -2.5% 7.21 320.0 22.0 328.0 28.0 440.0 150.0 326.8 30.5 61.1 DZ-3-53 -2.2% 1.86 321.0 19.0 328.0 21.0 275.0 79.0 328.7 23.0 46.1 DZ-3-54 -2.2% 5.45 324.0 22.0 331.0 33.0 430.0 110.0 330.5 36.0 71.9 DZ-3-55 -1.9% 4.63 324.0 13.0 330.0 15.0 207.0 77.0 330.9 17.0 33.9 DZ-3-56 6.2% 1.59 357.0 24.0 335.0 30.0 537.0 78.0 333.2 33.2 66.5 DZ-3-57 -3.4% 2.38 324.0 18.0 335.0 17.0 190.0 100.0 336.6 19.0 38.0 DZ-3-58 -3.3% 2.24 331.0 14.0 342.0 20.0 269.0 82.0 342.6 22.4 44.8 DZ-3-59 -4.1% 9.98 338.0 17.0 352.0 20.0 258.0 66.0 353.3 23.0 46.0 DZ-3-60 -5.4% 2.76 334.0 23.0 352.0 26.0 184.0 93.0 354.3 28.5 57.0 DZ-3-61 -2.0% 8.70 349.0 24.0 356.0 28.0 362.0 82.0 356.5 30.5 61.0 DZ-3-62 0.6% 2.73 359.0 20.0 357.0 21.0 329.0 79.0 357.5 23.8 47.5 DZ-3-63 -7.9% 2.39 330.0 17.0 356.0 23.0 86.0 67.0 359.4 25.8 51.6 DZ-3-64 0.3% 2.94 363.0 19.0 362.0 24.0 485.0 82.0 361.3 26.5 53.0 DZ-3-65 -4.3% 1.64 345.0 18.0 360.0 22.0 174.0 71.0 361.6 24.4 48.9 DZ-3-66 -4.6% 2.54 351.0 18.0 367.0 22.0 239.0 74.0 368.3 24.4 48.9 DZ-3-67 -2.5% 1.99 365.0 23.0 374.0 23.0 271.0 72.0 375.4 26.5 52.9 DZ-3-68 -5.3% 1.88 356.0 22.0 375.0 17.0 270.0 120.0 376.4 18.3 36.7 DZ-3-69 -8.8% 1.56 352.0 29.0 383.0 30.0 250.0 120.0 384.2 33.2 66.4 DZ-3-70 -4.1% 2.04 368.0 19.0 383.0 25.0 235.0 70.0 385.6 28.5 56.9 DZ-3-71 -7.3% 4.43 358.0 20.0 384.0 22.0 190.0 100.0 386.7 25.1 50.2 DZ-3-72 -0.7% 3.57 432.0 21.0 435.0 18.0 431.0 73.0 435.1 20.4 40.7 DZ-3-73 -0.5% 2.41 437.0 19.0 439.0 21.0 459.0 76.0 439.5 23.8 47.5 DZ-3-74 3.2% 2.94 464.0 20.0 449.0 15.0 648.0 91.0 446.5 17.7 35.3 DZ-3-75 4.9% 9.08 513.0 77.0 488.0 69.0 550.0 140.0 488.3 81.1 162.3 DZ-3-76 -0.2% 1.26 526.0 27.0 527.0 28.0 430.0 120.0 529.0 31.8 63.6 DZ-3-77 2.5% 10.72 552.0 25.0 538.0 25.0 580.0 100.0 537.7 28.5 56.9 DZ-3-78 9.3% 2.25 689.0 90.0 625.0 98.0 1200.0 140.0 617.2 114.7 229.4 DZ-3-79 12.3% 4.93 724.0 99.0 635.0 80.0 970.0 150.0 629.9 94.2 188.5 DZ-3-80 -4.2% 2.41 612.0 21.0 638.0 25.0 586.0 71.0 640.0 29.1 58.1 DZ-3-81 28.5% 1.98 1074.0 53.0 768.0 65.0 1794.0 55.0 729.0 81.2 162.4 DZ-3-82 0.1% 14.70 780.0 27.0 779.0 38.0 933.0 76.0 775.3 44.7 89.3 DZ-3-83 13.3% 3.77 962.0 89.0 834.0 94.0 1266.0 99.0 805.4 108.0 216.0 DZ-3-84 24.8% 2.83 1157.0 87.0 870.0 120.0 1880.0 110.0 833.5 141.3 282.6

120

Grain Disc. Th/U Apparent ages (Ma) Interpreted age (Ma) 207 235 206 238 Pb*/ U Pb*/ U Age 1σ Age 1σ Age 1σ Age 1σ 2σ DZ-3-85 -1.1% 1.96 912.0 45.0 922.0 43.0 940.0 97.0 921.2 51.2 102.4 DZ-3-86 1.9% 3.16 954.0 25.0 936.0 30.0 1073.0 76.0 925.7 37.9 75.8 DZ-3-87 3.9% 4.74 998.0 22.0 959.0 26.0 1110.0 58.0 953.4 31.9 63.7 DZ-3-88 1.4% 2.90 996.0 35.0 982.0 34.0 1071.0 65.0 978.9 41.3 82.7 DZ-3-89 -1.9% 4.02 968.0 35.0 986.0 33.0 963.0 75.0 988.3 40.7 81.3 DZ-3-90 9.3% 3.59 1102.0 37.0 999.0 56.0 1251.0 81.0 989.0 67.7 135.3 DZ-3-91 -5.3% 4.00 1033.0 36.0 1060.0 37.0 1007.0 63.0 1007.0 63.0 126.0 DZ-3-92 0.8% 3.92 987.0 28.0 1006.0 36.0 1014.0 66.0 1014.0 66.0 132.0 DZ-3-93 -4.1% 4.75 994.0 34.0 1029.0 50.0 988.0 68.0 1035.2 61.6 123.2 DZ-3-94 -4.5% 6.04 1070.0 34.0 1086.0 34.0 1039.0 73.0 1039.0 73.0 146.0 DZ-3-95 -8.1% 3.81 1137.0 33.0 1144.0 45.0 1058.0 78.0 1058.0 78.0 156.0 DZ-3-96 2.3% 2.41 1045.0 33.0 1044.0 42.0 1069.0 75.0 1069.0 75.0 150.0 DZ-3-97 5.7% 1.79 1050.0 33.0 1035.0 41.0 1098.0 68.0 1098.0 68.0 136.0 DZ-3-98 -14.0% 5.01 1055.0 32.0 1091.0 47.0 957.0 91.0 1098.9 58.2 116.4 DZ-3-99 4.1% 4.50 1093.0 36.0 1088.0 49.0 1134.0 74.0 1134.0 74.0 148.0 DZ-3-100 2.5% 2.81 1168.0 35.0 1161.0 43.0 1191.0 59.0 1191.0 59.0 118.0 DZ-3-101 3.2% 3.26 1186.0 73.0 1162.0 74.0 1200.0 110.0 1200.0 110.0 220.0 DZ-3-102 8.8% 4.37 1137.0 40.0 1099.0 41.0 1205.0 86.0 1205.0 86.0 172.0 DZ-3-103 -1.3% 28.00 1266.0 34.0 1258.0 52.0 1242.0 64.0 1242.0 64.0 128.0 DZ-3-104 7.5% 3.10 1141.0 26.0 1150.0 35.0 1243.0 82.0 1243.0 82.0 164.0 DZ-3-105 12.4% 2.82 1197.0 28.0 1149.0 36.0 1312.0 76.0 1312.0 76.0 152.0 DZ-3-106 4.2% 1.78 1311.0 38.0 1270.0 41.0 1325.0 81.0 1325.0 81.0 162.0 DZ-3-107 24.6% 4.54 1164.0 46.0 1033.0 43.0 1370.0 130.0 1370.0 130.0 260.0 DZ-3-108 0.0% 3.88 1414.0 44.0 1404.0 56.0 1404.0 82.0 1404.0 82.0 164.0 DZ-3-109 -1.1% 2.43 1409.0 42.0 1424.0 56.0 1408.0 75.0 1408.0 75.0 150.0 DZ-3-110 6.8% 2.23 1438.0 34.0 1421.0 47.0 1525.0 55.0 1525.0 55.0 110.0 DZ-3-111 0.6% 1.24 1520.0 50.0 1538.0 81.0 1548.0 89.0 1548.0 89.0 178.0 DZ-3-112 -6.3% 1.62 1574.0 52.0 1665.0 82.0 1566.0 82.0 1566.0 82.0 164.0 DZ-3-113 16.4% 2.32 1473.0 32.0 1366.0 45.0 1634.0 56.0 1634.0 56.0 112.0 DZ-3-114 -2.6% 1.89 1683.0 40.0 1676.0 53.0 1634.0 74.0 1634.0 74.0 148.0 DZ-3-115 6.2% 3.06 1584.0 56.0 1539.0 76.0 1641.0 72.0 1641.0 72.0 144.0 DZ-3-116 0.2% 1.89 1663.0 35.0 1642.0 56.0 1645.0 68.0 1645.0 68.0 136.0 DZ-3-117 2.6% 4.92 1637.0 45.0 1612.0 61.0 1655.0 77.0 1655.0 77.0 154.0 DZ-3-118 12.1% 3.54 1574.0 51.0 1465.0 84.0 1666.0 97.0 1666.0 97.0 194.0 DZ-3-119 13.6% 14.30 1521.0 48.0 1444.0 83.0 1671.0 83.0 1671.0 83.0 166.0 DZ-3-120 -1.8% 2.33 1707.0 37.0 1709.0 48.0 1678.0 60.0 1678.0 60.0 120.0 DZ-3-121 -1.5% 3.30 1691.0 35.0 1720.0 62.0 1694.0 56.0 1694.0 56.0 112.0 DZ-3-122 14.5% 1.61 1548.0 38.0 1486.0 46.0 1737.0 64.0 1737.0 64.0 128.0 DZ-3-123 9.8% 2.13 1671.0 34.0 1573.0 49.0 1744.0 54.0 1744.0 54.0 108.0 DZ-3-124 -4.8% 1.58 1800.0 34.0 1839.0 50.0 1755.0 61.0 1755.0 61.0 122.0 DZ-3-125 -4.4% 3.23 1791.0 41.0 1847.0 64.0 1769.0 52.0 1769.0 52.0 104.0 DZ-3-126 12.4% 3.26 1625.0 39.0 1551.0 65.0 1771.0 61.0 1771.0 61.0 122.0 DZ-3-127 -8.4% 1.76 1865.0 34.0 1929.0 61.0 1779.0 57.0 1779.0 57.0 114.0 DZ-3-128 -4.9% 1.43 1810.0 61.0 1867.0 78.0 1780.0 120.0 1780.0 120.0 240.0 DZ-3-129 3.7% 1.35 1774.0 35.0 1734.0 57.0 1801.0 59.0 1801.0 59.0 118.0 DZ-3-130 11.5% 2.18 1662.0 27.0 1599.0 44.0 1806.0 54.0 1806.0 54.0 108.0 DZ-3-131 5.0% 3.30 1759.0 48.0 1726.0 69.0 1817.0 68.0 1817.0 68.0 136.0 DZ-3-132 -5.7% 2.06 1903.0 40.0 1927.0 66.0 1823.0 59.0 1823.0 59.0 118.0 DZ-3-133 8.9% 6.70 1743.0 32.0 1692.0 68.0 1858.0 59.0 1858.0 59.0 118.0 DZ-3-134 1.1% 3.40 1853.0 39.0 1839.0 57.0 1860.0 42.0 1860.0 42.0 84.0 DZ-3-135 24.7% 1.98 1582.0 86.0 1410.0 140.0 1873.0 73.0 1873.0 73.0 146.0 DZ-3-136 21.4% 2.26 1624.0 44.0 1474.0 54.0 1876.0 65.0 1876.0 65.0 130.0 DZ-3-137 -7.3% 5.17 1953.0 46.0 2048.0 58.0 1909.0 58.0 1909.0 58.0 116.0 DZ-3-138 7.1% 1.15 1864.0 41.0 1794.0 56.0 1931.0 89.0 1931.0 89.0 178.0 DZ-3-139 -1.6% 1.22 1965.0 49.0 1994.0 88.0 1962.0 65.0 1962.0 65.0 130.0 DZ-3-140 9.0% 2.00 1863.0 37.0 1805.0 66.0 1983.0 62.0 1983.0 62.0 124.0 DZ-3-141 2.1% 1.85 2192.0 49.0 2181.0 56.0 2227.0 73.0 2227.0 73.0 146.0 DZ-3-142 -3.6% 1.40 2308.0 52.0 2373.0 97.0 2290.0 72.0 2290.0 72.0 144.0 DZ-3-143 9.9% 13.78 2389.0 33.0 2254.0 75.0 2502.0 60.0 2502.0 60.0 120.0 DZ-3-144 19.7% 2.84 2306.0 42.0 2042.0 76.0 2542.0 61.0 2542.0 61.0 122.0 DZ-3-145 -2.5% 2.89 2602.0 45.0 2621.0 61.0 2557.0 47.0 2557.0 47.0 94.0 DZ-3-146 15.1% 2.44 2404.0 37.0 2206.0 89.0 2598.0 45.0 2598.0 45.0 90.0 DZ-3-147 7.3% 1.10 2529.0 56.0 2410.0 110.0 2599.0 54.0 2599.0 54.0 108.0 121

Grain Disc. Th/U Apparent ages (Ma) Interpreted age (Ma) 207 235 206 238 207 206 Pb*/ U Pb*/ U Pb*/ Pb* Age 1σ Age 1σ Age 1σ Age 1σ 2σ DZ-3-148 -6.4% 2.23 2678.0 47.0 2810.0 110.0 2641.0 53.0 2641.0 53.0 106.0 DZ-3-149 23.5% 0.98 2372.0 39.0 2043.0 70.0 2671.0 45.0 2671.0 45.0 90.0 DZ-3-150 8.2% 11.40 2630.0 46.0 2505.0 93.0 2730.0 60.0 2730.0 60.0 120.0 DZ-3-151 1.8% 2.90 2732.0 54.0 2699.0 95.0 2748.0 46.0 2748.0 46.0 92.0

DZ-2 DZ-2-1 2.8% 1.55 276.2 9.2 268.6 9.1 359.0 75.0 267.6 10.2 20.4 DZ-2-2 2.9% 1.37 276.9 8.8 269.0 11.0 400.0 85.0 267.8 12.2 24.5 DZ-2-3 -9.8% 2.17 247.0 6.8 271.2 7.2 322.0 71.0 271.1 8.1 16.3 DZ-2-4 0.0% 1.32 276.3 9.3 276.4 9.7 298.0 64.0 276.1 10.9 21.7 DZ-2-5 2.0% 1.49 282.1 9.3 276.4 7.6 293.0 60.0 276.1 8.2 16.3 DZ-2-6 3.7% 1.88 291.0 8.4 280.3 7.2 383.0 79.0 279.1 8.1 16.3 DZ-2-7 7.6% 1.86 304.0 15.0 281.0 11.0 507.0 97.0 279.3 11.5 23.1 DZ-2-8 -1.8% 1.09 274.0 12.0 279.0 10.0 257.0 67.0 279.5 11.6 23.1 DZ-2-9 12.1% 1.64 323.0 12.0 284.0 11.0 599.0 97.0 281.7 12.2 24.5 DZ-2-10 3.7% 1.75 294.0 11.0 283.0 12.0 375.0 79.0 282.3 13.6 27.1 DZ-2-11 -0.2% 1.14 282.3 9.9 283.0 8.9 250.0 74.0 283.3 9.5 19.0 DZ-2-12 0.0% 1.92 284.0 10.0 284.0 11.0 290.0 99.0 283.5 11.5 23.1 DZ-2-13 -0.5% 1.56 284.0 8.0 285.4 8.7 257.0 66.0 284.0 9.5 19.0 DZ-2-14 1.3% 1.79 288.0 11.0 284.4 9.8 257.0 77.0 284.5 10.9 21.7 DZ-2-15 -1.9% 1.52 279.9 7.6 285.1 9.5 312.0 77.0 284.7 10.2 20.4 DZ-2-16 6.5% 1.74 306.2 8.6 286.4 8.8 440.0 75.0 284.8 9.5 19.0 DZ-2-17 3.8% 1.75 296.6 9.0 285.4 9.7 358.0 64.0 285.0 10.9 21.7 DZ-2-18 1.4% 1.96 289.0 10.0 285.0 10.0 278.0 64.0 285.6 10.9 21.7 DZ-2-19 -0.7% 1.70 283.9 7.2 285.9 9.3 256.0 67.0 286.5 10.2 20.4 DZ-2-20 -9.1% 1.88 263.0 9.9 287.0 11.0 316.0 61.0 286.5 12.9 25.8 DZ-2-21 2.0% 3.02 294.0 11.0 288.0 10.0 390.0 88.0 287.0 11.6 23.1 DZ-2-22 1.5% 1.95 292.0 8.9 287.6 9.3 310.0 74.0 287.2 10.2 20.4 DZ-2-23 -2.4% 2.14 280.2 9.5 287.0 8.1 258.0 84.0 287.3 8.8 17.7 DZ-2-24 0.9% 2.04 290.0 10.0 287.4 9.0 268.0 91.0 287.5 10.2 20.4 DZ-2-25 0.3% 2.27 288.0 11.0 287.0 10.0 287.0 86.0 287.6 11.5 23.1 DZ-2-26 -2.5% 1.63 281.0 11.0 288.0 13.0 263.0 73.0 288.2 13.6 27.2 DZ-2-27 0.1% 1.59 288.3 7.6 288.0 10.0 242.0 59.0 288.4 11.5 23.1 DZ-2-28 -6.9% 2.04 271.2 7.2 289.9 7.9 351.0 72.0 289.3 8.8 17.7 DZ-2-29 2.0% 2.15 295.8 9.6 290.0 11.0 336.0 90.0 289.6 12.2 24.5 DZ-2-30 -0.7% 2.11 288.2 9.5 290.1 7.8 305.0 67.0 289.8 8.8 17.7 DZ-2-31 2.0% 1.72 296.0 13.0 290.0 12.0 323.0 90.0 290.1 13.6 27.2 DZ-2-32 2.6% 2.28 299.0 10.0 291.1 6.0 352.0 86.0 290.7 6.7 13.3 DZ-2-33 -2.7% 2.05 283.0 10.0 290.7 8.7 229.0 75.0 291.0 9.5 19.0 DZ-2-34 -2.1% 1.72 284.9 8.5 290.9 9.4 300.0 83.0 291.1 10.2 20.4 DZ-2-35 -0.9% 1.87 289.1 8.3 291.6 8.4 285.0 67.0 291.7 9.5 19.0 DZ-2-36 -1.1% 2.74 289.0 7.0 292.3 8.2 303.0 61.0 292.2 8.8 17.7 DZ-2-37 -0.6% 2.30 290.5 9.3 292.3 9.2 289.0 76.0 292.3 10.2 20.4 DZ-2-38 5.1% 1.59 308.7 9.6 293.0 10.0 344.0 79.0 292.5 11.5 23.1 DZ-2-39 -8.4% 1.69 270.3 8.6 293.0 10.0 343.0 50.0 292.6 11.5 23.1 DZ-2-40 -1.8% 1.27 286.9 9.1 292.1 9.5 257.0 58.0 292.7 10.2 20.4 DZ-2-41 3.2% 2.26 303.3 9.3 293.7 7.4 380.0 84.0 292.8 8.2 16.3 DZ-2-42 -8.1% 1.70 271.1 9.7 293.0 9.9 297.0 68.0 292.9 10.9 21.7 DZ-2-43 0.9% 1.91 295.8 8.8 293.2 9.3 299.0 58.0 293.0 10.2 20.4 DZ-2-44 -1.0% 1.86 290.1 9.2 293.0 10.0 279.0 86.0 293.1 10.9 21.7 DZ-2-45 0.3% 2.02 294.0 12.0 293.2 9.5 336.0 79.0 293.3 10.2 20.4 DZ-2-46 2.9% 1.37 303.9 9.6 295.0 11.0 394.0 79.0 294.0 11.5 23.1 DZ-2-47 3.0% 1.25 304.1 7.6 295.1 7.7 372.0 48.0 294.2 8.2 16.3 DZ-2-48 -1.4% 1.84 290.5 9.8 294.7 9.6 334.0 96.0 294.3 10.9 21.8 DZ-2-49 2.5% 1.88 302.3 7.9 294.6 7.7 320.0 82.0 294.6 8.1 16.3 DZ-2-50 0.0% 1.95 295.0 10.0 295.0 10.0 258.0 88.0 295.0 11.5 23.1 DZ-2-51 2.4% 1.64 302.4 9.2 295.0 10.0 321.0 68.0 295.1 11.5 23.1 DZ-2-52 -5.5% 1.28 279.7 9.2 295.0 11.0 220.0 73.0 296.0 12.2 24.5 DZ-2-53 -9.3% 2.11 270.9 9.5 296.0 9.6 281.0 78.0 296.1 10.9 21.7 DZ-2-54 -1.2% 2.01 292.5 7.7 295.9 8.0 255.0 61.0 296.3 8.8 17.7 DZ-2-55 3.6% 1.56 309.0 16.0 298.0 13.0 440.0 100.0 296.4 14.3 28.5 DZ-2-56 0.0% 2.52 297.0 10.0 297.0 13.0 298.0 83.0 297.2 14.2 28.5

122

Grain Disc. Th/U Apparent ages (Ma) Interpreted age (Ma) 207 235 206 238 207 206 Pb*/ U Pb*/ U Pb*/ Pb* Age 1σ Age 1σ Age 1σ Age 1σ 2σ DZ-2-57 -4.7% 1.65 283.7 8.5 297.0 10.0 203.0 64.0 297.4 10.9 21.7 DZ-2-58 1.4% 1.86 301.9 8.4 297.8 8.2 341.0 70.0 297.6 8.8 17.7 DZ-2-59 9.6% 1.68 332.0 12.0 300.0 10.0 550.0 110.0 297.7 10.9 21.7 DZ-2-60 -0.5% 2.08 296.6 9.5 298.0 8.5 305.0 72.0 297.7 9.5 19.0 DZ-2-61 0.0% 1.54 300.0 12.0 300.0 11.0 314.0 67.0 297.9 12.9 25.8 DZ-2-62 0.4% 2.23 298.7 8.0 297.6 7.3 281.0 76.0 298.1 8.2 16.3 DZ-2-63 2.7% 1.98 307.0 11.0 298.6 8.8 326.0 79.0 298.4 9.5 19.0 DZ-2-64 1.0% 1.68 301.0 12.0 298.0 10.0 283.0 66.0 298.6 10.9 21.7 DZ-2-65 3.8% 1.79 312.0 10.0 300.0 11.0 428.0 85.0 298.6 12.2 24.5 DZ-2-66 -1.8% 2.05 293.8 9.9 299.0 11.0 263.0 91.0 298.7 12.2 24.4 DZ-2-67 -1.7% 2.19 293.5 9.7 298.5 8.9 257.0 82.0 298.8 9.5 19.0 DZ-2-68 -1.7% 2.30 295.9 9.5 301.0 11.0 320.0 80.0 298.8 11.5 23.1 DZ-2-69 21.3% 1.84 390.0 20.0 307.0 13.0 960.0 100.0 299.1 13.6 27.2 DZ-2-70 21.3% 2.65 389.0 24.0 306.0 11.0 880.0 160.0 299.5 12.2 24.4 DZ-2-71 0.7% 1.19 301.0 11.0 299.0 11.0 305.0 70.0 299.7 11.5 23.0 DZ-2-72 3.1% 1.56 310.7 7.6 301.0 10.0 441.0 65.0 299.8 10.9 21.7 DZ-2-73 -0.7% 1.92 297.0 10.0 299.0 11.0 276.0 77.0 299.9 11.5 23.1 DZ-2-74 1.0% 2.10 303.0 11.0 300.0 11.0 313.0 71.0 300.1 12.2 24.5 DZ-2-75 0.3% 1.71 302.0 9.8 301.0 10.0 303.0 73.0 300.9 10.9 21.7 DZ-2-76 10.5% 1.68 343.0 48.0 307.0 13.0 680.0 240.0 301.0 14.3 28.5 DZ-2-77 0.7% 2.25 303.0 10.0 301.0 11.0 349.0 75.0 301.2 11.4 22.8 DZ-2-78 1.5% 1.11 305.9 8.8 301.3 7.8 329.0 50.0 301.3 8.8 17.7 DZ-2-79 -1.2% 1.73 298.3 9.8 302.0 10.0 318.0 61.0 301.4 11.6 23.1 DZ-2-80 -0.7% 2.03 299.0 11.0 301.0 11.0 296.0 92.0 301.6 12.2 24.5 DZ-2-81 -0.9% 1.87 299.4 7.6 302.0 10.0 307.0 78.0 302.1 10.9 21.7 DZ-2-82 -5.2% 2.15 287.0 11.0 302.0 11.0 191.0 77.0 302.5 12.2 24.5 DZ-2-83 -0.1% 2.20 303.0 11.0 303.2 9.9 360.0 86.0 302.8 10.9 21.7 DZ-2-84 -2.3% 1.57 295.3 8.7 302.0 10.0 271.0 77.0 303.0 11.5 23.1 DZ-2-85 2.4% 1.97 311.0 12.0 303.6 9.6 313.0 76.0 303.4 10.9 21.7 DZ-2-86 1.9% 2.69 309.0 13.0 303.0 10.0 287.0 90.0 303.4 11.5 23.1 DZ-2-87 -5.2% 1.97 288.0 11.0 303.0 11.0 169.0 81.0 303.9 11.5 23.1 DZ-2-88 -1.2% 2.11 300.0 10.0 303.7 9.5 252.0 81.0 304.4 10.9 21.7 DZ-2-89 -3.8% 2.65 293.0 13.0 304.0 12.0 260.0 120.0 304.5 13.6 27.2 DZ-2-90 0.3% 2.43 306.0 10.0 305.0 12.0 281.0 96.0 304.8 13.6 27.1 DZ-2-91 -3.4% 2.42 294.1 9.7 304.0 11.0 211.0 72.0 305.4 12.2 24.4 DZ-2-92 -1.1% 1.97 301.9 8.7 305.3 9.6 252.0 65.0 305.7 10.9 21.7 DZ-2-93 1.0% 1.79 309.0 11.0 306.0 12.0 349.0 75.0 306.0 12.9 25.8 DZ-2-94 4.7% 1.79 322.0 13.0 307.0 13.0 394.0 75.0 306.4 13.6 27.2 DZ-2-95 0.6% 1.89 309.0 10.0 307.0 12.0 294.0 68.0 307.1 12.9 25.8 DZ-2-96 0.0% 2.67 307.0 12.0 307.0 10.0 309.0 84.0 307.7 11.6 23.1 DZ-2-97 -2.7% 1.86 300.0 11.0 308.0 13.0 286.0 83.0 308.5 14.3 28.5 DZ-2-98 -2.6% 2.29 301.1 9.7 309.0 11.0 229.0 75.0 309.6 12.2 24.4 DZ-2-99 3.2% 1.99 320.4 8.9 310.2 8.3 336.0 71.0 309.9 9.5 19.0 DZ-2-95 0.6% 1.89 309.0 10.0 307.0 12.0 294.0 68.0 307.1 12.9 25.8 DZ-2-100 -2.9% 1.82 301.0 11.0 309.7 9.9 289.0 88.0 309.9 10.9 21.7 DZ-2-101 -0.8% 1.35 307.5 9.2 310.0 11.0 316.0 66.0 310.2 12.2 24.4 DZ-2-102 0.3% 1.96 311.8 9.4 310.9 6.8 352.0 61.0 310.4 7.5 15.0 DZ-2-103 -1.6% 1.34 306.0 10.0 311.0 11.0 255.0 75.0 311.2 12.2 24.5 DZ-2-104 -0.2% 1.96 311.0 13.0 311.5 7.5 296.0 95.0 311.4 8.2 16.3 DZ-2-105 -2.8% 2.37 304.0 13.0 312.4 8.9 216.0 91.0 313.5 10.2 20.4 DZ-2-106 5.0% 1.54 331.0 12.0 314.6 9.0 434.0 75.0 313.6 10.2 20.4 DZ-2-107 -1.6% 2.16 310.0 11.0 315.0 10.0 267.0 80.0 314.8 10.9 21.7 DZ-2-108 -0.9% 1.57 314.0 12.0 316.9 9.5 285.0 86.0 317.4 10.9 21.7 DZ-2-109 -3.9% 1.91 305.4 9.2 317.2 9.3 268.0 77.0 317.9 10.2 20.4 DZ-2-110 -1.3% 1.37 315.0 14.0 319.0 14.0 335.0 89.0 318.5 15.6 31.2 DZ-2-111 -0.6% 1.92 317.0 12.0 319.0 11.0 358.0 76.0 318.9 11.4 22.9 DZ-2-112 -0.8% 1.75 318.3 9.7 321.0 12.0 284.0 60.0 321.5 13.6 27.2 DZ-2-113 -3.2% 1.87 313.1 9.9 323.2 9.2 332.0 85.0 322.9 10.2 20.4

DZ-1 DZ-1-1 17.3% 3.37 279.0 11.0 230.6 7.6 243.0 69.0 230.3 8.1 16.3 DZ-1-2 13.4% 4.48 268.0 12.0 232.0 11.0 260.0 120.0 232.2 11.5 23.1

123

Grain Disc. Th/U Apparent ages (Ma) Interpreted age (Ma) 207 235 206 238 207 206 Pb*/ U Pb*/ U Pb*/ Pb* Age 1σ Age 1σ Age 1σ Age 1σ 2σ DZ-1-3 29.4% 4.99 330.0 20.0 233.0 12.0 380.0 130.0 232.3 12.9 25.8 DZ-1-4 18.2% 3.93 292.0 15.0 239.0 15.0 320.0 110.0 239.1 17.0 33.9 DZ-1-5 10.4% 3.21 267.0 12.0 239.3 9.7 228.0 75.0 239.3 10.9 21.7 DZ-1-6 17.0% 3.11 289.0 15.0 240.0 10.0 237.0 95.0 239.8 10.9 21.7 DZ-1-7 16.3% 2.51 288.2 9.8 241.2 7.6 216.0 82.0 241.3 8.1 16.3 DZ-1-8 17.1% 4.12 293.0 11.0 242.8 9.7 324.0 87.0 242.3 10.8 21.7 DZ-1-9 15.6% 3.46 288.0 16.0 243.0 13.0 303.0 88.0 242.6 14.3 28.5 DZ-1-10 13.0% 4.94 284.0 15.0 247.0 12.0 380.0 130.0 244.0 12.9 25.8 DZ-1-11 16.4% 4.69 293.0 14.0 245.0 12.0 248.0 93.0 245.2 12.9 25.8 DZ-1-12 2.4% 2.65 254.0 9.2 247.8 9.6 211.0 74.0 248.2 10.2 20.4 DZ-1-13 20.6% 3.54 314.0 12.0 249.4 9.8 344.0 96.0 249.1 10.9 21.7 DZ-1-14 3.6% 3.85 259.0 10.0 249.7 9.7 245.0 85.0 249.6 10.9 21.7 DZ-1-15 12.5% 3.99 288.0 16.0 252.0 13.0 205.0 94.0 252.4 14.9 29.9 DZ-1-16 16.9% 4.30 305.0 12.0 253.5 9.4 328.0 88.0 252.8 10.2 20.4 DZ-1-17 13.0% 3.99 293.0 11.0 255.0 9.9 245.0 78.0 255.4 10.9 21.7 DZ-1-18 15.1% 2.51 304.0 16.0 258.0 11.0 253.0 91.0 256.0 12.9 25.8 DZ-1-19 11.9% 3.92 293.0 19.0 258.0 14.0 290.0 120.0 257.9 15.6 31.2 DZ-1-20 15.5% 3.61 309.0 13.0 261.0 11.0 255.0 73.0 261.5 12.2 24.4 DZ-1-21 -1.9% 3.95 266.0 14.0 271.0 11.0 300.0 110.0 270.4 12.2 24.4 DZ-1-22 14.1% 4.08 319.0 15.0 274.0 16.0 300.0 100.0 274.4 17.0 33.9 DZ-1-23 8.9% 10.64 303.0 19.0 276.0 16.0 340.0 110.0 275.5 17.6 35.3 DZ-1-24 9.1% 3.27 307.0 19.0 279.0 18.0 310.0 120.0 276.4 20.3 40.7 DZ-1-25 -0.6% 2.25 276.6 8.5 278.2 9.2 295.0 67.0 277.9 10.2 20.3 DZ-1-26 3.5% 3.75 289.0 12.0 279.0 10.0 370.0 84.0 278.0 10.9 21.7 DZ-1-27 -4.2% 4.69 265.0 14.0 276.0 14.0 70.0 120.0 278.0 14.9 29.9 DZ-1-28 1.8% 3.25 285.0 12.0 280.0 12.0 251.0 83.0 280.7 13.6 27.1 DZ-1-29 5.7% 3.29 300.1 9.5 283.0 11.0 361.0 73.0 281.7 11.6 23.1 DZ-1-30 9.3% 5.07 312.0 18.0 283.0 13.0 230.0 110.0 283.4 14.9 29.9 DZ-1-31 1.0% 3.34 288.0 12.0 285.0 10.0 275.0 86.0 283.8 10.9 21.7 DZ-1-32 -0.6% 4.34 283.3 8.6 285.0 10.0 322.0 71.0 284.7 10.9 21.7 DZ-1-33 4.1% 3.66 297.0 12.0 284.8 9.8 270.0 91.0 285.1 10.9 21.7 DZ-1-34 -0.7% 4.00 284.0 10.0 285.9 9.6 292.0 83.0 286.1 10.9 21.7 DZ-1-35 17.5% 4.25 349.0 17.0 288.0 13.0 500.0 150.0 286.3 14.3 28.5 DZ-1-36 -0.9% 3.78 284.4 7.0 287.0 7.9 300.0 73.0 286.7 8.8 17.6 DZ-1-37 3.4% 3.43 297.0 10.0 287.0 12.0 307.0 76.0 287.1 13.6 27.2 DZ-1-38 -1.8% 3.02 282.0 11.0 287.0 12.0 245.0 71.0 287.7 12.9 25.8 DZ-1-39 8.5% 3.02 316.0 14.0 289.0 14.0 257.0 73.0 288.2 15.6 31.2 DZ-1-40 -1.0% 3.53 287.0 10.0 290.0 11.0 323.0 79.0 289.6 12.2 24.5 DZ-1-41 -0.6% 4.51 288.0 11.0 289.7 9.1 307.0 80.0 289.8 10.2 20.4 DZ-1-42 -1.1% 3.91 288.0 12.0 291.2 9.1 277.0 67.0 291.3 10.2 20.3 DZ-1-43 3.4% 4.65 302.0 12.0 291.8 9.6 329.0 85.0 291.4 10.9 21.7 DZ-1-44 -3.9% 3.47 281.0 11.0 292.0 12.0 244.0 70.0 292.1 12.9 25.8 DZ-1-45 1.0% 3.95 298.0 13.0 295.0 12.0 303.0 72.0 292.8 12.9 25.8 DZ-1-46 -6.0% 4.65 275.4 9.3 292.0 10.0 223.0 82.0 292.8 11.5 23.1 DZ-1-47 -2.4% 2.79 286.0 12.0 293.0 12.0 328.0 74.0 293.1 12.9 25.8 DZ-1-48 18.6% 2.87 360.0 12.0 293.0 12.0 318.0 84.0 293.3 13.6 27.2 DZ-1-49 -6.3% 3.29 276.0 11.0 293.3 9.6 264.0 67.0 293.9 10.9 21.7 DZ-1-50 -5.4% 3.89 279.0 13.0 294.0 10.0 222.0 70.0 294.3 11.5 23.1 DZ-1-51 1.7% 2.86 300.0 11.0 295.0 10.0 368.0 67.0 294.3 11.6 23.1 DZ-1-52 1.7% 3.38 299.0 12.0 294.0 12.0 312.0 77.0 294.5 12.9 25.8 DZ-1-53 -5.7% 2.42 279.0 10.0 294.8 9.6 239.0 79.0 295.2 10.9 21.7 DZ-1-54 3.0% 3.52 303.0 10.0 294.0 13.0 250.0 110.0 295.2 14.3 28.5 DZ-1-55 15.6% 4.67 352.0 13.0 297.0 12.0 381.0 99.0 295.7 12.9 25.8 DZ-1-56 -4.8% 2.94 282.0 10.0 295.4 9.9 251.0 79.0 295.8 10.9 21.7 DZ-1-57 2.0% 4.04 305.0 14.0 299.0 14.0 317.0 87.0 295.8 14.9 29.9 DZ-1-58 4.5% 4.06 309.9 9.8 296.0 13.0 323.0 79.0 296.0 14.3 28.5 DZ-1-59 1.5% 5.48 300.5 9.9 296.0 10.0 292.0 76.0 296.1 11.5 23.1 DZ-1-60 1.3% 5.26 300.0 13.0 296.0 12.0 258.0 98.0 296.2 12.9 25.8 DZ-1-61 -3.1% 3.86 288.0 11.0 297.0 11.0 320.0 80.0 296.3 12.9 25.8 DZ-1-62 1.3% 3.06 303.0 12.0 299.0 10.0 303.0 69.0 298.4 10.9 21.7 DZ-1-63 -3.7% 3.64 288.3 9.7 299.0 12.0 295.0 70.0 299.1 13.6 27.2 DZ-1-64 -0.7% 3.81 297.0 11.0 299.0 10.0 275.0 81.0 299.5 10.9 21.7

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Grain Disc. Th/U Apparent ages (Ma) Interpreted age (Ma) 207 235 206 238 207 206 Pb*/ U Pb*/ U Pb*/ Pb* Age 1σ Age 1σ Age 1σ Age 1σ 2σ DZ-1-65 2.6% 3.21 308.0 12.0 300.0 11.0 330.0 71.0 300.0 11.5 23.1 DZ-1-66 -1.2% 2.83 296.5 9.2 300.2 9.1 299.0 71.0 300.3 10.2 20.4 DZ-1-67 -6.8% 2.53 280.9 9.7 300.0 11.0 228.0 63.0 300.9 12.2 24.5 DZ-1-68 0.7% 2.59 303.0 11.0 301.0 12.0 308.0 86.0 301.0 13.6 27.2 DZ-1-69 -9.5% 4.23 274.0 12.0 300.0 11.0 144.0 84.0 301.7 11.5 23.1 DZ-1-70 27.1% 3.79 414.0 16.0 302.0 13.0 222.0 78.0 302.8 14.3 28.5 DZ-1-71 7.9% 5.28 330.0 11.0 304.0 11.0 314.0 76.0 302.9 12.9 25.8 DZ-1-72 -8.5% 4.38 280.0 8.3 303.9 9.2 230.0 64.0 304.6 10.2 20.3 DZ-1-73 1.6% 5.37 310.0 12.0 305.0 11.0 252.0 71.0 305.8 12.2 24.5 DZ-1-74 -5.4% 3.05 289.4 9.3 305.1 9.4 235.0 73.0 305.8 10.2 20.4 DZ-1-75 0.0% 3.30 307.0 14.0 307.0 11.0 270.0 100.0 307.3 12.9 25.8 DZ-1-76 19.5% 3.15 383.0 12.0 308.5 8.6 342.0 85.0 307.9 9.5 19.0 DZ-1-77 29.4% 3.20 436.0 16.0 307.6 9.9 278.0 73.0 307.9 10.9 21.7 DZ-1-78 -1.7% 3.67 303.0 10.0 308.0 12.0 259.0 65.0 308.7 12.9 25.8 DZ-1-79 -6.2% 3.88 291.0 10.0 309.0 10.0 258.0 71.0 309.5 10.9 21.7 DZ-1-80 0.3% 3.06 312.0 15.0 311.0 14.0 245.0 70.0 311.3 15.6 31.2 DZ-1-81 21.2% 2.52 396.0 12.0 312.0 11.0 316.0 78.0 312.5 12.2 24.5 DZ-1-82 15.0% 3.25 367.0 11.0 312.0 11.0 148.0 83.0 314.1 12.2 24.4 DZ-1-83 13.8% 2.39 363.0 14.0 313.0 10.0 196.0 74.0 314.2 11.5 23.1 DZ-1-84 -3.6% 4.16 303.0 12.0 314.0 12.0 262.0 67.0 315.0 13.6 27.2 DZ-1-85 -3.6% 2.13 304.0 13.0 315.0 13.0 246.0 65.0 316.2 14.3 28.5 DZ-1-86 18.4% 2.41 398.0 18.0 324.7 9.4 1000.0 110.0 316.5 10.2 20.4 DZ-1-87 -7.4% 2.55 297.0 12.0 319.0 13.0 203.0 81.0 319.7 14.3 28.5 DZ-1-88 -2.9% 3.34 314.0 12.0 323.0 11.0 341.0 74.0 322.1 12.2 24.4 DZ-1-89 19.9% 2.78 407.0 15.0 326.0 14.0 332.0 76.0 326.7 15.6 31.2 DZ-1-90 -5.5% 3.45 309.0 13.0 326.0 13.0 171.0 85.0 326.8 14.9 29.9 DZ-1-91 18.0% 2.87 399.0 15.0 327.0 15.0 430.0 71.0 327.0 16.3 32.6 DZ-1-92 -9.6% 3.26 302.6 9.7 331.5 9.7 304.0 86.0 331.8 10.9 21.7 DZ-1-93 -4.4% 3.97 318.0 13.0 332.0 13.0 360.0 100.0 332.8 14.3 28.5 DZ-1-94 -9.5% 3.46 317.0 15.0 347.0 20.0 371.0 92.0 347.4 21.7 43.4 DZ-1-95 29.2% 0.94 524.0 25.0 371.0 21.0 1053.0 75.0 362.7 23.1 46.2 DZ-1-96 -7.7% 3.68 336.0 17.0 362.0 13.0 300.0 100.0 362.9 14.2 28.5 DZ-1-97 8.8% 3.26 488.0 21.0 445.0 21.0 470.0 100.0 444.4 23.7 47.5 DZ-1-98 23.6% 2.39 602.0 21.0 460.0 17.0 395.0 82.0 461.0 19.0 38.0 DZ-1-99 25.0% 1.10 621.0 20.0 466.0 17.0 519.0 61.0 465.4 19.7 39.4 DZ-1-100 0.4% 2.52 477.0 16.0 475.0 15.0 550.0 71.0 474.8 16.3 32.6 DZ-1-101 0.4% 2.10 515.0 21.0 513.0 25.0 647.0 80.0 511.1 27.8 55.7 DZ-1-102 6.7% 2.88 668.0 16.0 623.0 20.0 980.0 63.0 612.4 23.1 46.1 DZ-1-103 18.6% 4.49 884.0 30.0 720.0 30.0 1060.0 100.0 701.7 38.6 77.3 DZ-1-104 29.2% 8.05 1157.0 57.0 1034.0 39.0 1460.0 120.0 1460.0 120.0 240.0 DZ-1-105 -0.7% 0.81 1754.0 36.0 1753.0 56.0 1740.0 62.0 1740.0 62.0 124.0 DZ-1-106 8.5% 5.32 2261.0 32.0 1618.0 40.0 1769.0 47.0 1769.0 47.0 94.0 DZ-1-107 1.4% 4.31 560.0 19.0 1781.0 67.0 1807.0 84.0 1807.0 84.0 168.0 DZ-1-108 -0.7% 1.57 1816.0 31.0 1837.0 71.0 1825.0 73.0 1825.0 73.0 146.0 DZ-1-109 17.7% 0.84 1272.0 32.0 1539.0 46.0 1869.0 64.0 1869.0 64.0 128.0 DZ-1-110 13.9% 1.47 957.0 25.0 1663.0 56.0 1931.0 58.0 1931.0 58.0 116.0 DZ-1-111 13.1% 1.25 1893.0 30.0 1679.0 60.0 1931.0 48.0 1931.0 48.0 96.0 DZ-1-112 15.5% 0.53 1986.0 47.0 1870.0 66.0 2214.0 65.0 2214.0 65.0 130.0 DZ-1-113 20.5% 0.72 2732.0 48.0 1935.0 77.0 2433.0 49.0 2433.0 49.0 98.0

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