U-Pb Detrital Zircon Signature of the Ouachita Orogenic Belt

Home , Blakely Sandstone, Mazarn Shale, Novaculite, Ouachita orogeny, Womble Shale

U-PB DETRITAL ZIRCON SIGNATURE OF THE OUACHITA OROGENIC BELT

PRESTON REEVES McGUIRE

Bachelor of Arts, 2014

Western State Colorado University

Gunnison, Colorado

Submitted to the Graduate Faculty of

The College of Science and Engineering

Texas Christian University

In partial Fulfillment of the requirements for the degree

MASTERS OF SCIENCE IN GEOLOGY

May 2017

Preston Reeves McGuire

2017

Acknowledgements

I would like to gratefully acknowledge the help, support, and extreme generosity of all individuals and universities while working on the project.

I would first like to thank my graduate advisor, Dr. Xianyang Xie, for giving me this opportunity to study under his guidance. His enthusiasm has kept me motivated and excited about this project during the course of my stay at TCU. I could not have asked for a better advisor who was as dedicated and inspiring as Dr. Xie was. I would also like to thank my other thesis advisors, Dr. Helge Alsleben and Dr. Elizabeth Petrie, for their helpful criticisms and inputs. Their support and critiques during my research were very much appreciated.

Secondly, I would like to thank the help of the other geology departments that graciously offered their facilities and assistance in helping me complete this project: Dr. Fan and the

University of Texas at Arlington, Dr. William Griffin and the University of Texas at Dallas, and

Dr. George Gehrels and Dr. Mark Pecha at the University of Arizona.

I would like to thank Dr. William Thomas for his thoughtful input and assistance.

Without his input, this project would have been incredibly more difficult. Thank you for the guidance.

Lastly, I would like to thank my family and friends. This would not have been possible without the unconditional love and support from my other half, Emily, and my parents, Jane and

Reeves McGuire. Finally, I have to thank the great friends I have made here at TCU: John

Williams, John Weiss, Ali Gomez, Tyler Howe, and Robert White. You guys made my time here at TCU and created memories that will last a lifetime.

Table of Contents Acknowledgements……………………………………………………………………....ii LIST OF FIGURES……………………………………………………………………...v LIST OF TABLES…………………..…………………………………………………...v INTRODUCTION ...... 1 Motivation and Goal of Study...... 1 Previous Studies ...... 2 GEOLOGIC SETTING ...... 2 Tectonic History...... 2 Stratigraphy of the Ouachita Trough system ...... 3 Latest Precambrian – Ordovician ...... 3 Silurian – Mississippian ...... 4 Mississippian – Late Pennsylvanian ...... 5 METHODS ...... 5 Sampling and Unit Descriptions ...... 5 U-Pb detrital zircon geochronology ...... 8 NORTH AMERICAN DETRITAL ZIRCON SOURCES ...... 10 Archean and Paleoproterozoic (>1800 Ma) ...... 10 Late Paleoproterozoic (1600-1800 Ma) ...... 10 Early Mesoproterozoic (1300-1500 Ma) ...... 11 Middle-Late Mesoproterozoic (950-1250 Ma) ...... 11 Neoproterozoic to Early Paleozoic (~500-800 Ma) ...... 12 Paleozoic (320-500 Ma) ...... 12 RESULTS ...... 12 Ordovician Crystal Mountain Sandstone ...... 13 Ordovician Blakely Sandstone ...... 13 Ordovician Womble Shale ...... 13 Ordovician Polk Creek Formation ...... 14 Silurian Blaylock Sandstone ...... 14 Mississippian Hot Spring Sandstone ...... 14 Mississippian Stanley Group ...... 15

Summary ...... 15 DISCUSSIONS...... 15 Sedimentation to the Ouachita trough ...... 15 Ouachita Detrital Zircon Signature ...... 18 Broader implications of regional sediment dispersal in the southern mid-continent region 20 Arkoma Basin Comparison ...... 21 Marathon Basin Comparison ...... 22 CONCLUSIONS ...... 23

REFERENCES ...... 25

FIGURES ...... 32

Tables ...... 41

APPENDIX ...... 42 Tables: U-Pb Detrital Zircon Geochronology Data ...... 42 Concordia Plots ...... 43 VITA

ABSTRACT

List of Figures

1. Tectonic Setting and Study Area...... 33

2. Stratigraphic and Lithologic Column...... 34

3. Sample Location Map…...... 35

4. Pre-Mesozoic Age Belts of North America...... 36

5. Relative Age Probability Plot with Histogram...... 37

6. Normalized Age Probability Plot...... 38

7. Comparison Plot………………...... 39

8. Comparison Plot Excluding Grenville...... 40

9. Zipper Like Model………………...... 41

List of Tables

1. Sample Locations………………………………….…………………………………………42

2. Major age province percentages found in Ouachita samples..………………………………42

INTRODUCTION

Motivation and Goal of Study

During the Mississippian period, a major collision between Gondwana and Laurentia formed the Ouachita orogen, shifting the most active tectonism on the Laurentian continent from the Appalachian orogen to this area (Viele and Thomas, 1989). The Ouachita Mountains in

Arkansas, and the Marathon thrust belt in Texas are the only two exposures of the Ouachita orogenic belt (Keller and Cebull, 1973). In both areas, the pre-Mississippian passive margin sediments of southern Laurentia have been uplifted and provide a perfect window to study this ancient orogenic belt (Fig. 1). These uplifted passive margin strata of the Ouachita orogen have been pointed to as a major sediment source in North America from the Pennsylvanian to the early Cretaceous (Thomas, 1985; Viele and Thomas, 1989; Gleason et al., 2007; Dickinson and

Gehrels, 2009; Soreghan and Soreghan, 2013; Blum and Pecha, 2014). However, no systematic dataset has been established to evaluate sediments thought to be sourced from the recycled strata of the Ouachita orogen.

The Ouachita mountain belt represents the most complete, and by far the largest exposure of the passive margin sediments of the Ouachita orogen that can be easily accessed through different road cuts or state/national parks. In this project, all of the major Ordovician to

Mississippian siliciclastic strata were sampled and analyzed using U-Pb detrital zircon geochronology to document the overall detrital zircon age distributions of the Ouachita trough through the lower Paleozoic. The combined geochronologic data represents the first systematic study of the age signatures for the Ouachita orogen. The results have important implications for sediment dispersal and paleogeographic reconstructions in the mid-continent and surrounding areas.

Previous Studies

Much of the work that has been done on the lower Paleozoic rocks in the Ouachita

Mountain region is based in lithostratigraphy or structural geology. Flawn (1961) conducted much of the early work in the Ouachita Mountains and was the first to compile a complete stratigraphic section and tectonic history of the area. The geophysical study conducted by Keller and Cebull (1973) helped reconstruct the plate tectonic configuration of southern Laurentia.

Thomas (1976, 1985, 1991, 2006, 2010), Lowe (1985), and Viele and Thomas (1989) reconstructed the paleogeography of the Iapetan rifted margin of southern Laurentia and gave the name of the Ouachita trough to the embayment (Fig. 1). Stratigraphy and sedimentology studies of the Ouachita trough were conducted by Morris (1974a, b), Picha and Niem (1974), Sholes and

McBride (1975), Worrell (1984), and Sutherland (1988). The current structural framework of the

Ouachita Mountains has been outlined by Viele and Thomas (1989), and Arbenz (2008).

Graham et al. (1976) and Lowe (1985) were the first to attempt a provenance study on the lower

Paleozoic rocks using the Gazzi-Dickinson method of point counting. Gleason et al. (2002) conducted a U-Pb geochronologic study of two Ordovician sandstones, the Blakely and the

Blaylock, and dated < 25 grains in each as a proxy for sediment provenance of the lower

Paleozoic sediments of the Ouachita trough. However, a thorough and complete provenance study has not been completed in the lower Paleozoic rocks of the Ouachita Mountain area.

GEOLOGIC SETTING

Tectonic History

The breakup of Rodinia and the opening of the Iapetus Ocean is documented by synrift sedimentary and igneous rocks, a post-rift unconformity, and early post-rift sedimentary strata found along the eastern and southeastern United States and shows that Laurentia was isolated by

2 the early Cambrian (Thomas, 2006). Subsequently, younger sedimentary units buried the

Iapetan rift margin, but data from geophysical surveys and deep wells have allowed a palinspastic reconstruction of the rift geometry (Fig. 1B) (Viele and Thomas, 1989; Thomas,

1991, 2006). This zigzag rifted geometry of southern Laurentia created the embayment that is known as the Ouachita trough. Lowe (1985) suggests that this rift system includes additional sedimentary basins such as Southern Oklahoma aulacogen, Reelfoot Rift, Illinois Basin, and

Rome trough.

Over the course of the Paleozoic, there is the opening and closing of the Iapetus Ocean completing a full Wilson cycle (Arbenz, 1989). During the Devonian, a subduction zone developed to the east and southeast of Laurentia. Island arcs created during this period were subsequently accreted to the Laurentian continent during the assembly of Pangea in the

Mississippian (Arbenz, 2008). The assembly of Pangea resulted in the Alleghanian and Ouachita orogenies, which were complete by the Permian time (Keller and Cebull, 1973; Thomas, 1976;

Lowe, 1985; Thomas, 1985; Houseknecht, 1987; Viele and Thomas, 1989; Thomas, 1991, 2006,

2010).

Stratigraphy of the Ouachita Trough system

Latest Precambrian – Ordovician

The rock units that comprise the Ouachita orogen were originally deposited on the southern Laurentian margin in the Ouachita trough (Fig. 1) (Lowe, 1985). Sediments were accumulating in the trough from Cambrian until its closure during the Ouachita orogeny in the

Mississippian (Flawn, 1961). From the Cambrian to the Ordovician, deposition of primarily shallow water marine carbonates with few siliciclastics was occurring on the shelf and slope that formed in the northern part of the Ouachita trough. Deep marine shales were forming off the

3 slope to the south in the basin center (Flawn, 1961). Flawn (1961) recorded no depositional interruptions or angular unconformities in the pre-Mississippian strata. Based on the distribution of shallow and deep water units the paleogeography is interpreted as a marine slope with the margin being close to the north (Flawn, 1961; Arbenz, 1989). During this time there is an overall sea level transgression with 2nd and 3rd order intermitted regressions (Haq and Schutter, 2008).

In the study area there are three sandstone formations that were deposited in this shale and carbonate prone basin from the Cambrian to the Silurian; the Lower Ordovician Crystal

Mountain Sandstone, the Middle Ordovician Blakely Sandstone, and the Upper Ordovician to

Silurian Blaylock Sandstone (Fig. 2). These sandstones are interpreted as extensive turbidite sequences that were fed by deep water sand channels and fans (Morris, 1974a, b; Arbenz, 1989).

Quartzose sands of the Blakely and Crystal Mountain sandstones are interpreted to have come from the continental interior, whereas paleocurrent indicators in the silty arenites of the Blaylock

Sandstone suggest a southeastern source such as offshore island arcs, but uncertainty is high

(Worrell, 1984).

Silurian – Mississippian

From earliest Silurian to Mississippian, the Ouachita trough continues to experience a time of tectonic quiescence as the ocean reached its widest and deepest (Viele and Thomas,

1989). During this time, the Ouachita trough changed from a carbonate and shale prone basin to predominantly carbonate and novaculite deposition throughout the basin with the exception of the deposition of the Blaylock Sandstone. This change is interpreted to represent a basin wide sea level drop during this time favoring a carbonate factory throughout the Ouachita trough and increasing dissolved silica in the water column (Thomas, 1976; Haq and Schutter, 2008). The most dominant formation in the Ouachita system at this time is the Silurian-Late Devonian

Arkansas Novaculite. This is an aerially extensive formation throughout the Ouachita orogen that is characterized by its massive, light-colored, extremely fined grained, homogeneous novaculite with interbedded siliceous chert nodules (Sholes and McBride, 1975).

Mississippian – Late Pennsylvanian

Closure of the Ouachita trough began in the early Mississippian and concluded in the late

Pennsylvanian as shown by the increased sedimentation rates shown by the rapid influx of silty to sandy facies of the Mississippian Stanley Group (Arbenz, 2008). Deformation of the Ouachita trough is thought to end the deposition of the Stanley group, and included thrusting of the deep- water deposits northward onto the shallow marine deposits, which created the Ouachita Orogen

(Morris, 1974a). Limited tectonic activity has occurred in this orogen since the Permian, and weathering and erosion are responsible for the present mountains.

METHODS

Sampling and Unit Descriptions

A total of 27 samples were collected from the major sand bodies and shales that outcrop within and adjacent to the Ouachita thrust belt. Rock units ranging in age from Ordovician to

Mississippian were sampled to document the provenance of sediments deposited within the

Ouachita trough. My sampling strategies include: 1) sandstone formations as the highest priority followed by sandy intervals in the shales; and 2) samples that are known to be taken from correct formations with lower or upper formation contacts found for reference at each sample location.

At the end, seven samples were selected for U-Pb detrital zircon analysis, including Crystal

Mountain Sandstone, Blakely Sandstone, Womble Shale, Polk Creek Shale, Blaylock Sandstone,

Hot Spring Sandstone, and the Stanley Shale (Fig. 2, 3, Table 1).

The Early Ordovician Crystal Mountain Sandstone is described as a tan to light gray, fine to medium grained, well sorted quartz arenite that is quartz cemented thickly bedded and structureless. It is a cliff and ridge former that has minor interbedded gray laminated shales that are <0.5 m thick. The Crystal Mountain Sandstone lies conformably on the Cambrian Collier

Shale, conformably below the Ordovician Mazarn Shale and is up to 260 meters thick (Ferguson,

1920; Morris, 1974b; Arbenz, 1989).

The Early to Middle Ordovician Blakely Sandstone is a varicolored, fine grained and well sorted quartz arenite that has thin interbedded gray, green, and black shales and siltstones with very thin interbedded limestones. Graptolites and conodonts have been reported in the sandstone beds (Ulrich, 1911). The Blakely Sandstone lies conformably on the Ordovician Mazarn Shale and conformably below the Ordovician Womble Shale and ranges in thickness from <3 to 215 meters (Ulrich, 1911; Morris, 1974b).

The Middle Ordovician Womble Shale is a dark gray to black graptolitic shale that is highly fractured and fissile with interbedded phosphatic sandstones in the lower sections of the formation, and grey to blueish limestones in the upper sections. The Womble Shale lies conformably on the Blakely sandstone and conformably under the Bigfork Chert and is 150 to

360 meters thick (Miser, 1917; Morris, 1974b). The sandstone sampled for this study is from the lower section of the formation and is dark grey, very fine to fine grained and well sorted subfelsarenite.

The Late Ordovician Polk Creek Shale is a dark gray to black shale that is thinly bedded, fissile, graptolitic, and highly fractured with minor black chert and gray sandstones and limestones. The Polk Creek lies conformably on the Ordovician Bigfork Chert, conformably below the Silurian Blaylock Sandstone and is 15 to 70 meters thick (Purdue, 1909; Morris,

1974b). The sampled sandstone bed from the middle to upper section of the Polk Creek formation and is a light gray, medium grained, very well sorted and rounded quartz arenite with a quartz cement and is structureless.

The Silurian Blaylock Sandstone consists of gray to greenish, very fine to medium grained, poorly sorted wacke sandstone that is laminated and thinly bedded with the occasional fairly thick bed of ~2 meters. The formation also has some interbedded black fissile shales and fossils are rare with the occasional graptolite and trace fossil. The Silurian Blaylock Sandstone lies conformably on the Ordovician Polk Creek, conformably below the Silurian Missouri

Mountain Shale and is 365 meters thick in the southern Ouachita Mountains then thins drastically to the north, where it is commonly only 1 to 6 meters thick (Purdue, 1909; Morris,

1974b; Worrell, 1984).

The Mississippian Stanley Group is predominantly dark grey to black fissile shale with pyritic nodules and interbedded sandstones, tuffs, and cherts. There is a thick sandstone member called the Hot Springs Sandstone near the base of the sequence that was sampled. The Hot

Springs Sandstone is tan to orange, fine to coarse grained, poorly sorted and structureless subfelsarenite. The Hot Spring Sandstone Member is about 60 meters thick near Hot Springs,

Arkansas, but is less than 5 meters thick in other places in the Ouachita Mountains (Flawn, 1961;

Morris, 1974b).

A thin sandstone in the upper part of the Stanley Group sequence was also sampled. This sandstone is light grey, fine to medium grained, well sorted and quartz dominated. The Stanley

Group lies conformably above the Devonian Arkansas Novaculite, disconformably below the

Pennsylvanian Jackfork Group and varies in thickness from 1065 meters to 3050 meters

(including the Hot Springs Member) (Flawn, 1961; Morris, 1974b).

U-Pb detrital zircon geochronology

Sample preparation was conducted at Texas Christian University, University of Texas at

Dallas, and the University of Texas at Arlington. Samples were first crushed to gravel sized pieces using a jaw crusher, and then pulverized in a disk mill to produce sand sized particles.

Metal filings were removed using a hand magnet before using a gold pan and a Wilfley table to remove the clay minerals. Samples then underwent a magnetic separation using a Frantz LB-1 separator with a front slope of 10º and a side slope of 20º. The sample underwent three passes through the Franz at different magnetic intensities of 0.25, 0.5, and 1 amp. The non-magnetic portion was then subjected to a density separation using the heavy liquid technique. Methylene iodide (ρ = 3.3 g/cm3) and the samples were added to a separatory funnel to allow the heavy mineral fraction to separate and settle. The final heavy portion of the sample was then poured into a petri dish with isopropyl alcohol for further inspection and picking if necessary. Zircon grains were then sent to the University of Arizona LaserChron center where the grains were put into epoxy with the labs standard grains and ground to expose the core of the zircon crystals.

Samples are then imaged using a backscattered electron detector to map laser ablation pits in homogenous portions of the crystal to avoid errors that could occur in fractures, inclusions, or overgrowths.

The U-Pb geochronology was conducted by laser ablation-multicollector-inductively coupled plasma mass spectrometry (LA-MC-ICPMS) at the University of Arizona LaserChron

Center. Approximately 100 grains are analyzed to create a statistical confidence during the interpretation. Crystals are selected at random and only omitted if the grain was smaller than the laser diameter, or if a homogenous section could not be obtained. The analyses involve ablation of zircon with a Photon Machines Analyte G2 excimer laser using a spot diameter of 20 microns.

The ablated material is carried in helium into the plasma source of a Nu HR ICPMS, which is equipped with a flight tube of sufficient width that U, Th, and Pb isotopes are measured simultaneously. All measurements are made in static mode, using Faraday detectors with 3x1011 ohm resistors for 238U, 232Th, 208Pb, 206Pb, and discrete dynode ion counters for 204Pb and 202Hg.

Ion yields are ~0.8 mv per ppm. Each analysis consists of one 15-second integration on peaks with the laser off (for backgrounds), 15 one-second integrations with the laser firing, and a 30 second delay to purge the previous sample and prepare for the next analysis. The ablation pit is

~15 microns in depth.

Common Pb correction is accomplished by using the Hg-corrected 204Pb and assuming an initial Pb composition from Stacey and Kramers (1975). Uncertainties of 1.5 for 206Pb/204Pb and

0.3 for 207Pb/204Pb are applied to these compositional values based on the variation in Pb isotopic composition in modern igneous rocks. Inter-element fractionation of Pb/U is generally ~5%, whereas apparent fractionation of Pb isotopes is generally <0.2%. In-run analysis of fragments of a large zircon crystal (generally every fifth measurement) with known age of 563.5 ± 3.2 Ma

(2-sigma error) is used to correct for this fractionation. The uncertainty resulting from the calibration correction is generally 1-2% (2-sigma) for both 206Pb/207Pb and 206Pb/238U ages. The

206Pb/207Pb age is used for grains that are older than 800 Ma, and the 206Pb/238U age for younger grains.

Concentrations of U and Th are calibrated relative to Arizona LazerChron Center’s Sri

Lanka standard zircon as the main standard used, which contains ~518 ppm of U and 68 ppm Th,

206Pb/204Pb = 18,000, and a concordant age of 563.5 ± 3.2 Ma (2σ). Other standards used were;

R33 derived from a dioritic dyke of the Braintree Complex of Vermont, and FC Duluth Gabbro from Minnesota, which have ID-TIMS ages of 419.3 ± 0.4 Ma and 1099 ± 2 Ma respectively

(Schmitz et al., 2003; Black et al., 2004). Analyses that are greater than 20% discordant or >5% reverse discordant are not used in the final interpretation. These tight cutoffs are selected as only

71 of 908 grains analyzed do not fit the constraints. The age-probability diagrams were created by using Isoplot 3.0 and Excel programs from Arizona Laserchron Lab (Ludwig, 2008).

NORTH AMERICAN DETRITAL ZIRCON SOURCES

Zircon provenance interpretations are based on the correlation of zircon ages to the ages of known basement provinces of North America and accreted terranes (Fig. 4).

Archean and Paleoproterozoic (>1800 Ma)

Crust that could provide detrital grains with these age ranges are found in the northern most portion of the Laurentian continent. Grains with an age of >2500 Ma are correlated to the

Laurentian cratonic crust of the Wyoming-Hearne and Superior provinces (Hoffman, 1989; Van

Schmus et al., 1993; Van Schmus et al., 1996). The Wyoming-Hearne crust was buried during the Paleozoic, so a Superior interpretation is favored for grains that are 2500 Ma or older

(McKee et al., 1967). Grains with an age range 1950-2100 Ma are found in Trans-Amazonian crust, but this crust is not near the Ouachita trough until Mississippian time when the Iapetus

Ocean is closing (Lopez et al, 2001). Grains with an age range of 1800-1950 Ma can be correlated to Penokean basement of the Great Lakes area or the Trans-Hudson crust that separates the Wyoming-Hearne and Superior basements (Van Schmus et al., 1993). Again, the

Trans-Hudson crust is buried during the Paleozoic, so a Penokean interpretation is favored over the Trans-Hudson interpretation for this study (Soreghan and Soreghan, 2013).

Late Paleoproterozoic (1600-1800 Ma)

This age range is typical of the Yavapai (1700-1800 Ma) and Mazatzal (1600-1700 Ma) terranes. These terranes are made up of metavolcanic and metasedimentary aggregated rocks that

10 extend across the central and southwest regions of North America (Van Schmus et al., 1993).

This crust is the main component that makes up the Ancestral Rocky Mountains orogen that began its uplift in latest Mississippian time and ended in the Permian (Dickinson and Gehrels,

2003; Sharrah, 2006; Gehrels et al., 2011; Soreghan and Soreghan, 2013).

Early Mesoproterozoic (1300-1500 Ma)

These ages match the midcontinent igneous activity of the Granite-Rhyolite Province.

This time was characterized by anorogenic magmatism associated with scattered plutons across the midcontinent (Van Schmus et al., 1996). These rocks were also uplifted in the southeast portion of the Ancestral Rocky Mountains (Hoffman, 1989; Van Schmus et al., 1993; Van

Schmus et al., 1996; Gehrels et al., 2011), and were also exposed as a result of the breakup of

Rodina (Thomas, 1976; Viele and Thomas, 1989; Thomas, 1991, 2006).

Middle-Late Mesoproterozoic (950-1250 Ma)

This age population is consistent with the Grenville Orogen of eastern North America, northern Mexico, and parts of Africa (Hoffman, 1989; Van Schmus et al., 1993). This is the most dominant age population in North America and is found in sandstones ranging in age from

Neoproterozoic to Cretaceous (Gleason et al., 2002; Dickinson and Gehrels, 2003; Becker et al.,

2005; Sharrah, 2006; Gleason et al., 2007; Dickinson and Gehrels, 2009; Park et al., 2010;

Gehrels et al., 2011; Soreghan and Soreghan, 2013; Blum and Pecha, 2014). This crust was exposed during the breakup of Rodina and again during the Taconic orogeny (Thomas, 1976;

Viele and Thomas, 1989; Thomas, 1991; Van Schmus et al., 1993; Thomas, 2006). The

Oaxaquia crust (1000-1250 Ma) found in Mexico is equivalent to the Grenville crust and is likely undistinguishable from Grenville sourced zircons in this study (Lopez et al., 2001).

Neoproterozoic to Early Paleozoic (~500-800 Ma)

This population of ages is correlated to peri-Gondwanan terranes (i.e. Coahuila, Sabine,

Suwanee, and Yucatan-Campeche). These terranes were sutured to the Laurentian continent just before the collision with Gondwana (Mueller et al., 1994; Aleinikoff et al., 1995; Ingle-Jenkins et al., 1998; Lopez et al., 2001; Weber et al., 2006). This population also correlates to localized igneous activity on the Laurentian continent like the Wichita Igneous Province (~530 Ma)

(Hanson and Eschberger, 2014), and pre-Iapetan rift plutons of northeastern Laurentia (513-723

Ma) (Dickinson and Gehrels, 2009).

Paleozoic (320-500 Ma)

The Taconic (490-440 Ma) and the Acadian (420-350 Ma) orogenies of the Appalachian

Mountains could have provided sediment to the study area (Simonetti and Doig, 1990; Coath and

Harrison, 2000; Aleinikoff et al., 2002). Additionally, the southern portion of the Yucatan-

Campeche terrane (400-430 Ma) could have potentially shed sediment to the study area after it is sutured to the Laurentian continent (Weber et al., 2006). Note that there is significant overlap between the Acadian and the Yucatan-Campeche ages.

RESULTS

Detrital zircon geochronology analyses yielded 908 acceptable concordance ages from the seven samples. Major age populations include the Superior Province (>2500 Ma),

Yavapai/Mazatzal Terrenes (1600-1800 Ma), Granite-Rhyolite Mid-Continent Province (1360-

1600 Ma), and the Grenville Province (950-1250 Ma) (Hoffman, 1989; Van Schmus et al., 1993;

Mueller et al., 1994; Aleinikoff et al., 1995; Ingle-Jenkins et al., 1998). Grains younger than 950

Ma are grouped together due to significant age overlap between source areas in this age range

12 and this overlap is discussed in detail later. Overall, the data show a clear change in sediment source contributions to the Ouachita trough in the lower Paleozoic (Figs. 5, 6, Table 2).

Ordovician Crystal Mountain Sandstone

The Ordovician Crystal Mountain Sandstone (n = 98) yielded an age range from 1012 Ma to 3169 Ma. It is characterized by three peaks at 1085, 1381, and 2654 Ma with grains related to the Superior Province making up 41% of the total population, Grenville population at ~28% and

Granite-Rhyolite Mid-Continent Provinces at 30%. Additionally, there is one grain at 1856 Ma

(1%) (Fig. 5, Table 2).

Ordovician Blakely Sandstone

The Ordovician Blakely Sandstone (n=108) sample has an age range from 982 Ma to

2712 Ma with the same three major age populations as the Crystal Mountain sample. It includes the Grenville (55%), Granite-Rhyolite Mid-Continent (24%), and the Superior (15%) provinces with peaks at 1077 Ma, 2705 Ma, and a double peak for the Granite-Rhyolite population at 1354

Ma and 1449 Ma (Fig 5, Table 2). There is a minor age cluster of the Yavapai/Mazatzal terranes

(6%). In comparison to the Crystal Mountain Sandstone, the main difference is that the Grenville peak becomes the dominant peak, the Granite-Rhyolite peak shifts from a single to a double peak, and a reduction of the Superior peak (Fig. 5, Table 2).

Ordovician Womble Shale

The Ordovician Womble Shale sample (n=101) contains an age range from 1105 Ma to

1764 Ma, and only has two age populations of Grenville Province (33%) and Granite-Rhyolite

Mid-Continent (63%) with peaks at 1118 Ma and 1366 Ma. Additionally, there are four grains with ages that correlate to the Yavapai/Mazatzal Terranes (4%) (Fig. 5, Table 2). This sample

13 differs from the Blakely as the Granite Rhyolite Province dominates this sample and there are no contributions of grains from the Superior Province.

Ordovician Polk Creek Formation

The Ordovician Polk Creek Formation (n=109) shows an age range from 977 Ma to 2815

Ma, and is dominated by Grenville Province ages (77%), with the dominant peak at 1041 Ma and a less dominant peak at 1157 Ma (Fig. 5, Table 2). Additionally, this sample produced two minor age populations from the Granite-Rhyolite Province (10%) and the Superior Province (13%), with peaks at 1401 Ma and 2677 Ma. In comparison to previous samples, the Grenville Province is the dominant contributor, and there is a significant reduction in the Granite-Rhyolite contribution (from 63% to 10%).

Silurian Blaylock Sandstone

The Silurian Blaylock Sandstone (n=301) produced an age range from 458 Ma to 2694

Ma. It is characterized by a prominent double peaking Grenville population (81%) with the peaks at 1049 Ma and 1163 Ma, a major age population from the Granite-Rhyolite Mid-Continent

Province (15%), and some minor ages from the Yavapai/Mazatzal Terranes (<2%) and the

Superior Province (<2%) (Fig. 5, Table 2). This sample is similar to the Polk Creek with the double peaking Grenville population being dominant, but with less influence from the Superior

Province. In comparison to previous sample, there are two younger grains with ages of 458 Ma and 720 Ma, which normally can be correlated with the Taconic Orogeny and pre-Iapetan rift plutons, respectively. Additionally, the 458 Ma grain is the first Paleozoic grain in this study.

Mississippian Hot Spring Sandstone

The Mississippian Hot Spring Sandstone of the Stanley Group (n=99) yielded an age range from 373 Ma to 2739 Ma, and bears three major age populations from the <950 Ma group

(17%), the Grenville Province (56%), and the Granite-Rhyolite Mid-Continent Province (15%), with the peaks at 423 Ma, 1060 Ma, and 1470 Ma, respectively. This sample also had few grains with age ranges of the Yavapai/Mazatzal Province (8%) and the Superior Province (3%) (Fig. 5,

Table 2). Additionally, this sample had two grains at 2263 Ma and 2268 Ma.

Mississippian Stanley Group

The Mississippian Stanley Group (n=92) produced the broadest age range from 336 Ma to 3228 Ma, with multiple age populations (Fig. 5, Table 2). The dominant age populations are the <950 Ma population (52%) and Grenville Province (24%). Additionally, there are grains with ages from 1952-2094 Ma (11%) that can be correlated to the Trans-Amazonian Province. Among the seven analyzed samples, this is the first sample showing possible contributions from

Gondwanan crust.

Summary

In general, the data can be divided into pre- and post-Mississippian subsets, as the major shift occurs sometime just prior to and definitely after the deposition of the Silurian Blaylock

Sandstone. The Grenville and Mid-Continent peaks dominate pre-Mississippian strata with the depletion of the Superior Province peaks from the North American craton through time. Post-

Mississippian data, on the other hand, shows the major shift with substantial Paleozoic ages.

DISCUSSIONS

Sedimentation to the Ouachita trough

During the Ordovician time, the Ouachita trough received sediments that originated from three major provinces (Figs. 5, 6); the Superior Province (>2500 Ma), Granite-Rhyolite Mid-

Continent Province (1360-1600 Ma), and the Grenville Province (950-1350 Ma). Significant input from these sources are thought to be a result of exposed Mid-Continent Granites-Rhyolites

15 and Grenville crust after the opening of the Iapetus Ocean in the late Precambrian (Fig. 1) (Viele and Thomas, 1989; Thomas, 2006). However, it is difficult to further constrain using the available data if the detritus linked to the Superior Province is due to primary erosion or recycling from secondary sources. Regardless, the number of grains derived from the Superior

Province deposited in the Ouachita trough decreases through the Ordovician. The decrease in the

Superior grains indicates that the trough is only receiving sediment from localized sources due to the local tectonics, such as the uplift of the Ozark Dome that could block sediment coming from the north (Kolata et al., 1986; Kolata and Nelson, 1990). There is also an increase in Grenville ages, while the Granite-Rhyolite ages decrease through the Ordovician, with the exception of the

Womble (see below). This ratio shift in the Grenville and Granite-Rhyolite is interpreted to indicate that the exposed Granite-Rhyolite crust initially exposed after the break apart of Rodinia started to be completely covered by the coastal to shelf carbonate rocks to the north of the

Ouachita trough. Meanwhile, the trough continued to receive input from the Grenville-aged crust to the east and northeast as active tectonism related to the Taconic orogeny continued to uplift

Grenville crust in the Appalachian area during the Ordovician (Aleinikoff et al., 2002).

The dominant Granite-Rhyolite peak of the Womble Shale sample can be interpreted to reflect the initial uplift of the Ozark Dome during the Middle to Late Ordovician (Kolata et al.,

1986; Kolata and Nelson, 1990). The lack of Superior age grains also suggest that the Ozark

Dome might have cut off, or at least temporarily blocked, the influence from the Superior

Province to the north. The Womble Shale sample was collected from the lower sandy section of the formation that is considered equivalent to the unconformity between the Everton and St.

Peter formation in the Ozark region. This unconformity could be attributed to both a sea level low-stand and the continued uplift of the Ozark Dome. Pickell (2012) dated the sandstones of the

Ordovician Everton and the St. Peter Formations in the Ozark region in northern Arkansas. Even though both formations are more proximal to the dome, they lack a very strong Granite-Rhyolite peak that is present in the Womble Shale. This inconsistency can be elucidated by that the

Granite-Rhyolite sediments would most likely bypass and deposit in the sandy section of the

Womble Shale to the south during the sea level low-stand. When the sea level continued to rise

(Haq and Schutter, 2008), the influence of the Granite-Rhyolite Province from the Ozark Dome was substantially reduced again. At the same time, grains of Grenville age are most likely continuing to come from the Appalachian area and Superior Province ages are either coming directly from the north or recycled with the Grenville aged grains. Overall, the Ordovician samples record the influence of local tectonics from the north and east, and the development of the passive margin of southern Laurentia after the breakup of Rodinia.

During the Silurian, the Blaylock continues to record the emerging dominance of

Grenville-aged zircons being supplied to the Ouachita trough with the decrease of grains derived from mid-continental and Superior Province sources (Figs. 5, 6, Table 2). Additionally, the

Silurian Blaylock Sandstone records the initial sediment influx from the approaching

Appalachians terranes to the Ouachita trough area. This is consistent with Gleason et al. (2007), who suggest the arrival of orogenic clastic sediment from the Appalachians by ~455 Ma. The

Blaylock Sample has one grain with an age of 458 ± 11 Ma and one grain dated at 720 Ma ± 12

Ma. The former may be related to the Taconic orogen to the east, whereas the latter could be derived from a peri-Gondwanan terrane or 513-723 Ma plutons along the eastern margin of

Laurentia related to the Neoptroterozoic pre-Iapetan rift (Dickinson and Gehrels, 2009). Both grains are likely recycled into the Ouachita trough with other sediments from the northeast

17 because the Iapetan Ocean is still open and there is no peri-Gondwanan terranes close by at the time.

The Mississippian samples record a major shift in the sedimentation to the Ouachita trough, as 32% of the grains analyzed in these samples are <900 Ma. These grains could be attributed to primary deposition sourced from the Pan-African-Brasiliano orogen and peri-

Gondwana terranes (Coahuila, Sabine, Suwanee, and/or Yucatan) (~400-700 Ma) shortly after the collision of Laurentia and Gondwana (Lopez et al., 2001; Weber et al., 2006), or recycled orogenic detritus from the Appalachian foreland (~320-500 Ma) with possible influence from the

Wichita Igneous Province (~530 Ma) (Becker et al., 2005; Hanson and Eschberger, 2014). The

Trans-Amazonian age grains (1950-2100 Ma) found in the Stanley suggest influence from the

Gondwanan side of the suture, but it is most likely a combination of all three potential sources due to the Ouachita trough being located at the intersection of these tectonic provinces.

Nonetheless, this shift in the detrital zircon age population with the presents of the Trans-

Amazonian grains represents the transformation from a passive to an active margin south of the

Ouachita trough and the suturing of Laurentia and Gondwana.

Ouachita Detrital Zircon Signature

Many workers have pointed to the Ouachita orogen as a major sediment source on the

North American continent from the Pennsylvanian to the Cretaceous (Thomas, 1985; Viele and

Thomas, 1989; Gleason et al., 2007; Dickinson and Gehrels, 2009; Soreghan and Soreghan,

2013; Blum and Pecha, 2014). However, there has been no systematic study to document the detrital zircon signature of sediments stemming from the Ouachita belt, or to discern the difference between sediments stemming from the Appalachian orogen and the Ouachita orogen.

The new detrital zircon data suggest that the Ouachita source is characterized by a strong

Grenville and Granite-Rhyolite peak with minor contributions from the Superior Province and

<950 Ma detrital zircon populations (Fig. 7). Thus, this dataset provides an Ouachita source signature to compare and assess the Ouachita orogen as a sediment source.

The detrital zircons of the pre-Pennsylvanian rocks from the Ouachita trough that were uplifted represent the sediment source of the Ouachita orogen (Fig. 7). Overall, the Ouachita source has roughly ½ Grenville grains, ¼ Granite-Rhyolite grains, and the other ¼ being a combination of <950 Ma and Superior aged grains. The dominant population correlates to the

Grenville Province and makes up more than half of the total population (53%) with a major peak at ~1060 Ma and a minor peak at ~1140 Ma (Fig. 7). The second dominant population is the

Granite-Rhyolite Province making up 22% with a major peak at ~1380 Ma and a minor peak at

~1450 Ma, and the Superior Province is the third major population and makes up 9% peaking at

~2660 Ma. Additionally, there are about 7% of the grains within <950 Ma age range.

It has been a challenge to differentiate between Appalachian sourced sediments and

Ouachita sourced sediments due to potential recycling issues (Gleason et al., 1994). Compiled detrital zircon data from the Appalachian foreland (Park et al., 2010) show that there three major age populations: 1) the Granite-Rhyolite Province (18% with a peak at ~1480 Ma), 2) Grenville

Province (~64%, evenly distributed double peaks at ~1055 Ma and ~1160 Ma), and 3) the

Paleozoic to Neoproterozoic population (10%, peaking at ~460 Ma), plus one minor Superior age cluster (Fig. 7).

There are similarities with the Appalachian data, but differences can be observed when comparing the detrital zircon data from this study. First the Grenville population differs between the two data sets. The Appalachian data set shows an evenly distributed double peak that is approximately 64% of the total population. In contrast, the Ouachita data shows both a major

19 peak and a minor peak and only make up 53% of the total population. Second, the Granite-

Rhyolite population differs. The Appalachian data peak at ~1480 Ma and make up only 18% of the total population, whereas the Ouachita data have a younger Granite-Rhyolite peak at ~1380

Ma and a minor peak at ~1450 Ma and make up 22% of the population. Third, the Superior population is much more significant and defined in the Ouachita data than in the Appalachian data, whereas the <950 Ma population is more defined and substantial in the Appalachian data.

Because the Grenville Province was the most dominant population in all of the data, that age range was removed to emphasize subtle differences between the datasets (Fig. 8). This highlights the difference in the Granite-Rhyolite peaks as the Appalachian data show a younger minor peak at ~1350 Ma and an older major peak at ~1480 Ma. In contrast, the Ouachita data have a younger major peak at ~1380 Ma and an older minor peak at ~1450 Ma. Removing the

Grenville population also emphasizes that the Superior population is more significant in the

Ouachita data and the <950 Ma population is more defined in the Appalachian data.

Broader implications of regional sediment dispersal in the southern mid-continent region

Enormously thick turbidite deposits of the Atoka Formation in the Arkoma Basin and the

Haymond Formation in the Marathon Basin accumulated during the Upper Mississippian to

Middle Pennsylvanian (McBride, 1966; Viele and Thomas, 1989; Sharrah, 2006; Gleason et al.,

2007). Previously, the deformed and uplifted lower Paleozoic rocks of the Ouachita trough were thought to create part of the sediment source for the upper Paleozoic synorogenic turbidites as the fold and thrust belt developed. However, it has been speculated that other sediment sources located to the north and northwest have contributed to the Pennsylvanian Atoka and Haymond

Formations (Houseknecht, 1986, 1987; Viele and Thomas, 1989; Sharrah, 2006; Gleason et al.,

2007).

Arkoma Basin Comparison

The Pennsylvanian Atoka Formation in the Arkoma Basin shows four major age populations associated with Grenville ages (46% with a major peak at ~1050 Ma),

Yavapai/Mazatzal ages (14% with a peak at ~1610 Ma), Granite-Rhyolite ages (13% with double peaks at ~1340 Ma and ~1470 Ma), and a detrital zircon age population <950 Ma (9% with a peak at ~420 Ma) (Sharrah, 2006). Both the Ouachita and Arkoma datasets show the Grenville ages are the most prominent population, but the most noticeable differences are the strong

Yavapai/Mazatzal peak and wider distribution in the Granite-Rhyolite population in the Arkoma data (Fig 7, 8). Also, the <950 Ma population in the Ouachita data has a wider distribution when compared to the Arkoma dataset. These differences, along with paleocurrent data that show sediment transportation from the north and northeast, indicate that there is little or no contribution to the Atoka Formation from the Ouachita orogen, despite the proximal location to the thrust belt. Sharra (2006) suggested that the Atoka Formation was likely derived from the northeast, consistent with Archer and Greb’s (1995) Amazon-scale river system that drained the

Appalachian foreland to the Ouachita embayment area during the Pennsylvanian. When comparing the Atoka data with the Appalachian foreland data from Park et al. (2010) the <950

Ma population is quite similar; however, the absence of evenly distributed double peaks of the

Grenville population seen in the Appalachian foreland, a relatively smaller contribution from the

Mid-Continent province, and a significant contribution from the Yavapai/Mazatzal crust seen in the Arkoma data, which is absent in the Appalachian foreland suggest there are other sources involved.

Marathon Basin Comparison

The Marathon Basin also contains mass accumulations of turbidite and steep fan delta deposits shown by the Pennsylvanian Haymond Formation (McBride, 1966). Gleason et al.

(2007) studied the provenance of the Haymond Formation in detail and provide a great comparison to my dataset. The combined age plot from the Haymond Formation shows few similarities between the Ouachita data and the Haymond data indicating that the Ouachita orogen has little influence on sedimentation to the Marathon basin. The Haymond Formation has two major age populations of the Grenville (39%) with a major peak at ~1125 Ma and a minor peak at ~1237 Ma, and the <950 Ma population (15%) with a major peak at ~530 Ma and two minor peaks at ~321 Ma and ~418 Ma. There is also a significant Granite-Rhyolite population of 9% and a Yavapai/Mazatzal at 13%, with a few grains that correlate to the Trans-Amazonian crust

(1950-2100 Ma) at 4%.

The Ouachita signature is indiscernible in the Haymond data due to proposed source mixing. There is an increase in the <950 Ma population and the significant influence of proximal

Yavapai/Mazatzal crust in the Marathon system. This increase in the Paleozoic grains is most likely due to a heavier influence from the Gondwanan terranes to the south of the suture as shown by the boulder beds in the lower Haymond that were dated at 330 Ma (Palmer et al., 1984;

Denison et al., 2005), where Lopez (2001) documented a 331±4 Ma age for the Las Delician Arc of Mexico thought to represent the Coahuila Terrane. The Trans-Amazonian grains are another piece of evidence for Gondwanan influence. The increase in Paleozoic grains is also thought to be a result of possible influence from the Wichita Igneous Provence based on the strong peak at

530 Ma.

Gleason et al. (2007) interpreted the Haymond to have received sediments from the

Ouachita orogen, the Laurentian craton, uplifted seafloor strata from the remnant ocean to the southwest, and Gondwanan crust. The suturing between Laurentia and Gondwana progressed from northeast to southwest during the Ouachita orogeny in such a way that McBride (1989) described this suturing as “zipper like” (Fig. 9). Gleason et al. (2007) suggests the remnant ocean depocenter (Marathon Embayment) to the southwest of the suturing was receiving significant recycled detritus from the Ouachita Mountains based on paleocurrent data indicating transport from N-NE, along with the other detritus from the other mentioned source areas. Contrary to previous interpretation, the detrital signature defined in this study suggests that the Ouachita orogen was not the main source to the Marathon Embayment. Sedimentation to the Marathon

Embayment was likely a result of mixing local with more distal sources.

CONCLUSIONS

In this study, a total of seven samples that represent the sediments shed from the Ouachita orogenic belt were collected from the core of the Ouachita Mountains and were analyzed using

U-Pb detrital zircon geochronology. The main conclusions from this study include:

1. Overall, the detrital zircon signature of the Ouachita orogenic belt and associated

sediments is characterized by roughly ½ Grenville grains, ¼ Granite-Rhyolite grains, and

the other ¼ being a combination of <950 Ma and Superior Province aged grains.

2. A major source shift occurred sometime after the deposition of the Silurian Blaylock

Sandstone and before the middle Mississippian Stanley Group. This major shift in the

detrital zircon age population around the lower Mississippian boundary is interpreted to

represent the transition from a passive to an active margin in the Ouachita trough system

based on the arrival of sediment stemming from peri-Gondwanan terranes and heavy

influence from the Appalachian region.

3. The Grenville and Mid-Continent Granite-Rhyolite peaks dominate pre-Mississippian

strata with the depletion of the Superior Province peaks from the North American craton

through time. The early Ordovician samples were receiving the majority of their sediment

from the Superior and Granite-Rhyolite provinces. By the late Ordovician, a shift occurs

to a more Grenville sourced sedimentation with the exception of the Womble Shale

sample. The prominent Granite-Rhyolite peak of the Womble Shale sample is interpreted

to represent the initial uplift of the Ozark Dome to the north. Silurian samples show a

return to the Grenville dominance and the initial sediment influence from newly accreted

Appalachian terranes to the north.

4. The signature from this study was used to compare the deformed lower Paleozoic rocks

of the Ouachita trough to the upper Paleozoic synorogenic turbidites that formed in the

Arkoma and Marathon Basins adjacent to the Ouachita orogenic belt. The presence of a

strong Yavapai/Mazatzal peak and wide distribution in the Granite-Rhyolite population

seen in the Pennsylvanian Atoka Formation in the Arkoma Basin indicates that there is

little or no contribution from the Ouachita orogen, despite the proximal location to the

thrust belt. Also, the Ouachita detrital signature is indiscernible in the Haymond data

indicating that the Ouachita orogen did not have significant influence on sedimentation to

the Marathon Basin.

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FIGURES

Figure 1. (A) Map of Appalachian/Ouachita frontal thrust belt showing the study area. (B) Map of Iapetan rifted margin of southern Laurentia, showing rift margins, transform faults, and synrift intracratonic basement fault system of the southern Oklahoma aulacogen (modified from Thomas (2010)). Note the Alabama-Oklahoma transform and the Ouachita rift create the Ouachita trough

geometry. 32

Figure 2. Stratigraphic and lithologic column of the Paleozoic rocks in the Ouachita Mountains and Arkoma Basin. Red dot represents sampled sand bodies. Gray represents unconformity. Black represents shale, yellow is sandstone, grey with (x) is microcrystalline quartz, white with texture (in McAlester) is coal. This figure only depicts depositional time and lithology. Column does not represent formation thickness.

Insert B

Insert A A

Figure 3. (A) Map of the Ouachita Mountain area in Oklahoma and Arkansas showing the pre- Mississippian (black), Mississippian (white), and post-Mississippian (gray) strata. Modified from Gleason et al. (2002). (B) Sample locations (red diamonds) displayed on the geologic map of the Ouachita Mountains with only the major thrust faults displayed. Legend only shows colors of sampled formations. To reference other colors, see map DGM-OMR-001 from the Arkansas Geological Survey.

Figure 4. Map showing pre-Mesozoic major age belts of North America. The hachured areas represent the Ancestral Rocky Mountains. Modified from Gehrels et al. (2011).

Figure 5. Relative age probability plot with histogram from the seven samples.

Figure 6. Normalized probability age plot with known source terranes shaded in color.

Figure 7. Normalized probability age plot comparing the combined Ouachita data representing all of the Ordovician-Mississippian samples (Ouachita signature), combined Appalachia data (Park et al., 2010), Atoka Formation data from the Arkoma Basin (Sharra, 2006), and Haymond Formation data from the Marathon Basin (Gleason et al,, 2007).

Figure 8. Normalized probability age plot of the comparing the data from figure 7 excluding the Grenville age range (950-1250 Ma) to highlight subtle differences.

Figure 9. “Zipper like model” put forth by McBride (1989) and Gleason (2007) showing deposition to the Marathon Embayment.

Tables

Table 1. U-Pb detrital zircon sampling units and sample locations

Sample Location Crystal Mountain N 34º 40’ 16.28”, W 93º 12’ 38.97” Blakely N 34º 31’ 39.25”, W 93º 20’ 08.60” Womble N 34º 32’ 27.11”, W 93º 28’ 34.67” Polk Creek N 34º 33’44.70”, W 93º 01’ 06.03” Blaylock N 34º 21’ 22.01”, W 93º 50’ 51.55” Hot Spring N 34º 34’ 07.13”, W 93º 01’ 08.14” Stanley N 34º 19’ 23.05”, W 93º 50’ 41.28”

Table 2. Percentages of major age provinces found in Ouachita samples

<950 Ma Grenville Granite-Rhyolite Yavapai/Mazatzal Superior Stanley 52.0% 24.0% -- 3.0% 4.0% Hot Spring 16.0% 56.0% 15.0% 8.0% 3.0% Blaylock -- 81.0% 15.0% 1.7% 1.7% Polk Creek -- 77.0% 10.0% -- 13.0% Womble -- 33.0% 63.0% 4.0% -- Blakely -- 55.0% 24.0% 6.0% 15.0% Crystal Mountain -- 28.0% 30.0% -- 41.0%

APPENDIX

Tables: U-Pb Detrital Zircon Geochronology Data

Table 1. Crystal Mountain

Best age CM-12 Isotope ratios Apparent ages (Ma)

Analysis ± ± error ± ± ± ± 207Pb/235U* 206Pb/238U 206Pb/238U 207Pb/235U 206Pb/207Pb (%) (%) corr. (Ma) (Ma) (Ma) (Ma) (Ma)

CM 76 1.7572 3.3 0.1747 3.2 0.97 1038.1 30.4 1029.8 21.3 1012.3 17.1 1012.3 17.1 CM 42 1.8473 3.2 0.1820 3.1 0.96 1077.7 30.4 1062.5 20.9 1031.4 16.9 1031.4 16.9 CM 16 1.8954 3.3 0.1848 3.2 0.97 1093.2 32.3 1079.5 22.1 1051.9 16.7 1051.9 16.7 CM 108 1.9113 3.3 0.1860 3.1 0.96 1099.4 31.6 1085.0 21.8 1056.3 19.1 1056.3 19.1 CM 22 1.8247 3.1 0.1770 3.0 0.96 1050.7 29.0 1054.4 20.5 1062.2 18.4 1062.2 18.4 CM 72 1.8861 2.3 0.1825 2.2 0.93 1080.6 21.5 1076.2 15.4 1067.4 16.5 1067.4 16.5 CM 87 1.9086 2.2 0.1840 2.1 0.94 1088.9 21.0 1084.1 14.9 1074.5 15.8 1074.5 15.8 CM 31 1.9247 2.4 0.1851 2.3 0.94 1094.6 23.0 1089.7 16.3 1079.9 16.7 1079.9 16.7 CM 94 1.9219 2.2 0.1847 2.1 0.94 1092.6 21.4 1088.7 15.0 1081.0 14.8 1081.0 14.8 CM 27 1.8883 2.2 0.1812 2.1 0.94 1073.8 20.4 1077.0 14.6 1083.5 15.3 1083.5 15.3 CM 19 1.9114 3.3 0.1834 3.1 0.96 1085.7 31.3 1085.1 21.8 1083.8 18.3 1083.8 18.3 CM 93 1.9154 2.6 0.1838 2.4 0.93 1087.8 24.2 1086.5 17.4 1083.8 19.4 1083.8 19.4 CM 43 1.8721 2.8 0.1795 2.6 0.95 1064.3 25.9 1071.3 18.4 1085.4 16.8 1085.4 16.8

CM 23 1.8911 1.8 0.1810 1.7 0.94 1072.5 17.1 1078.0 12.2 1089.0 12.9 1089.0 12.9 CM 3 2.0208 1.9 0.1933 1.8 0.91 1139.3 18.3 1122.5 13.1 1090.3 16.0 1090.3 16.0 CM 89 1.9337 3.1 0.1843 3.0 0.97 1090.7 30.2 1092.8 20.7 1097.1 13.8 1097.1 13.8 CM 84 1.9427 2.2 0.1847 2.1 0.96 1092.8 21.5 1095.9 15.0 1102.2 12.8 1102.2 12.8 CM 107 1.9831 2.2 0.1875 2.1 0.96 1107.7 21.9 1109.8 15.2 1113.9 12.9 1113.9 12.9 CM 35 2.0313 3.1 0.1917 2.9 0.95 1130.6 30.1 1126.1 20.8 1117.3 19.5 1117.3 19.5 CM 69 2.0879 2.7 0.1959 2.5 0.93 1153.1 26.7 1144.8 18.6 1129.2 19.9 1129.2 19.9 CM 39 2.0541 2.8 0.1927 2.7 0.96 1135.8 28.2 1133.6 19.3 1129.5 16.2 1129.5 16.2 CM 65 2.0373 2.6 0.1896 2.4 0.94 1119.2 25.1 1128.1 17.7 1145.1 17.8 1145.1 17.8 CM 60 1.9436 4.9 0.1784 4.7 0.97 1058.4 46.2 1096.2 32.9 1172.3 25.1 1172.3 25.1 CM 78 2.8637 2.3 0.2413 2.1 0.94 1393.5 26.5 1372.4 17.0 1339.7 15.4 1339.7 15.4 CM 6 2.8297 3.7 0.2383 3.6 0.98 1377.8 44.6 1363.5 27.6 1341.0 14.5 1341.0 14.5 CM 103 2.8478 3.2 0.2387 3.1 0.95 1380.0 38.0 1368.2 24.1 1349.9 18.4 1349.9 18.4 CM 24 2.7934 4.9 0.2340 4.7 0.96 1355.7 57.8 1353.8 36.7 1350.8 24.8 1350.8 24.8 CM 28 2.9400 3.7 0.2461 3.7 0.98 1418.3 46.6 1392.3 28.4 1352.6 15.4 1352.6 15.4 CM 4 2.7848 4.3 0.2324 4.1 0.97 1347.1 50.2 1351.5 31.9 1358.4 20.6 1358.4 20.6 CM 37 2.8173 3.6 0.2344 3.5 0.97 1357.7 43.3 1360.1 27.3 1364.0 17.0 1364.0 17.0 CM 81 2.8411 2.6 0.2359 2.5 0.95 1365.4 30.8 1366.5 19.9 1368.2 16.5 1368.2 16.5 CM 15 2.9311 2.1 0.2429 2.1 0.96 1401.8 25.9 1390.0 16.3 1371.9 12.2 1371.9 12.2 CM 38 2.8888 2.8 0.2394 2.7 0.97 1383.4 33.4 1379.0 20.8 1372.1 12.4 1372.1 12.4 CM 13 2.9776 2.8 0.2464 2.7 0.97 1420.0 34.8 1401.9 21.3 1374.5 12.6 1374.5 12.6 CM 85 2.9650 2.4 0.2451 2.3 0.95 1413.3 29.1 1398.7 18.3 1376.5 14.7 1376.5 14.7 CM 36 2.9380 2.6 0.2429 2.5 0.96 1401.5 31.9 1391.7 19.9 1376.8 13.5 1376.8 13.5 CM 5 2.8381 2.8 0.2346 2.7 0.96 1358.6 33.4 1365.7 21.2 1376.8 14.3 1376.8 14.3 CM 83 2.8261 2.6 0.2335 2.5 0.95 1352.9 30.2 1362.5 19.5 1377.6 15.0 1377.6 15.0 CM 17 2.8730 2.8 0.2370 2.6 0.94 1370.9 32.3 1374.9 20.9 1381.0 18.0 1381.0 18.0 CM 104 2.9303 3.1 0.2416 2.9 0.94 1394.9 36.8 1389.8 23.6 1381.9 19.9 1381.9 19.9 CM 29 2.8573 3.0 0.2355 2.9 0.96 1363.3 35.5 1370.7 22.6 1382.3 16.3 1382.3 16.3 CM 105 2.9311 3.1 0.2410 3.0 0.98 1392.1 37.8 1390.0 23.4 1386.7 13.1 1386.7 13.1

CM 9 2.9200 2.5 0.2401 2.4 0.96 1387.0 30.0 1387.1 18.9 1387.3 13.1 1387.3 13.1 CM 34 2.8752 2.6 0.2360 2.5 0.95 1366.0 30.7 1375.4 19.8 1390.1 15.9 1390.1 15.9 CM 100 2.9151 2.8 0.2393 2.7 0.97 1382.8 33.6 1385.8 21.2 1390.5 14.0 1390.5 14.0 CM 25 2.5936 3.6 0.2128 3.5 0.98 1244.0 39.9 1298.8 26.4 1390.7 14.5 1390.7 14.5 CM 46 2.8965 2.4 0.2370 2.3 0.94 1371.2 28.1 1381.0 18.3 1396.1 15.7 1396.1 15.7 CM 77 2.9531 2.5 0.2416 2.4 0.96 1395.1 29.6 1395.6 18.6 1396.4 12.7 1396.4 12.7 CM 32 3.1708 2.2 0.2530 2.1 0.96 1454.1 27.9 1450.1 17.2 1444.2 12.1 1444.2 12.1 CM 56 3.1026 2.9 0.2474 2.7 0.93 1425.0 34.7 1433.3 22.3 1445.7 19.6 1445.7 19.6 CM 73 3.2251 2.5 0.2538 2.4 0.95 1458.2 31.6 1463.2 19.7 1470.5 14.5 1470.5 14.5 CM 90 3.2369 2.8 0.2546 2.7 0.97 1462.3 35.3 1466.0 21.6 1471.5 12.7 1471.5 12.7 CM 49 3.3811 2.6 0.2629 2.5 0.97 1504.9 33.5 1500.0 20.3 1493.2 12.8 1493.2 12.8 CM 96 3.3666 2.5 0.2606 2.4 0.96 1492.7 31.5 1496.7 19.2 1502.3 12.5 1502.3 12.5 CM 11 3.1805 3.4 0.2399 2.8 0.80 1386.3 34.3 1452.4 26.4 1550.6 38.1 1550.6 38.1 CM 48 3.2376 6.7 0.2390 5.9 0.88 1381.3 73.8 1466.2 52.3 1591.5 59.3 1591.5 59.3 CM 50 5.2398 2.5 0.3348 2.4 0.95 1861.7 38.9 1859.1 21.5 1856.2 13.5 1856.2 13.5 CM 30 11.1264 2.9 0.4915 2.8 0.96 2577.2 58.7 2533.8 26.7 2499.2 13.0 2499.2 13.0 CM 98 10.8554 2.1 0.4779 1.9 0.94 2518.1 40.3 2510.8 19.1 2505.0 11.5 2505.0 11.5 CM 20 12.3512 1.9 0.5125 1.8 0.95 2667.3 40.4 2631.5 18.3 2604.0 10.2 2604.0 10.2 CM 71 12.2417 2.9 0.5066 2.8 0.98 2642.1 60.6 2623.1 26.9 2608.5 10.4 2608.5 10.4 CM 80 12.3387 3.3 0.5083 3.2 0.98 2649.3 69.7 2630.5 30.8 2616.1 10.9 2616.1 10.9 CM 68 12.3101 2.1 0.5059 1.9 0.93 2639.0 41.9 2628.3 19.6 2620.1 13.2 2620.1 13.2 CM 82 11.4615 2.1 0.4704 2.0 0.95 2485.3 41.8 2561.5 19.9 2622.2 11.1 2622.2 11.1 CM 1 12.5965 4.2 0.5159 4.1 0.98 2681.9 91.0 2650.0 39.9 2625.6 14.8 2625.6 14.8 CM 44 12.6194 2.1 0.5122 2.0 0.96 2666.1 44.6 2651.7 20.0 2640.7 9.8 2640.7 9.8 CM 66 12.8982 3.3 0.5232 3.2 0.98 2712.5 71.2 2672.2 30.8 2641.9 9.6 2641.9 9.6 CM 75 12.8681 2.4 0.5218 2.3 0.97 2706.9 50.8 2670.0 22.4 2642.2 9.7 2642.2 9.7 CM 70 12.4905 3.5 0.5061 3.4 0.98 2640.0 74.6 2642.0 33.0 2643.6 11.2 2643.6 11.2 CM 62 12.5247 2.0 0.5069 1.9 0.94 2643.5 40.6 2644.6 18.6 2645.4 10.8 2645.4 10.8 CM 61 12.4769 2.0 0.5045 1.9 0.95 2633.0 41.7 2641.0 19.2 2647.1 11.0 2647.1 11.0

CM 14 12.7925 1.9 0.5160 1.8 0.93 2682.3 39.9 2664.5 18.3 2651.0 11.6 2651.0 11.6 CM 53 12.7343 3.3 0.5135 3.2 0.98 2671.5 69.7 2660.2 30.7 2651.6 11.9 2651.6 11.9 CM 57 13.0540 3.1 0.5260 3.0 0.96 2724.6 66.3 2683.6 29.2 2652.8 13.7 2652.8 13.7 CM 64 13.0777 2.2 0.5252 2.1 0.96 2721.1 46.2 2685.3 20.6 2658.4 10.7 2658.4 10.7 CM 8 13.1160 2.5 0.5262 2.4 0.96 2725.5 53.4 2688.0 23.7 2660.0 12.2 2660.0 12.2 CM 92 12.7669 4.3 0.5115 4.2 0.99 2662.9 92.2 2662.6 40.3 2662.4 11.1 2662.4 11.1 CM 2 12.9434 3.7 0.5185 3.6 0.98 2693.0 79.2 2675.5 34.7 2662.4 12.8 2662.4 12.8 CM 45 13.0514 2.5 0.5222 2.4 0.97 2708.7 53.8 2683.4 23.7 2664.4 10.2 2664.4 10.2 CM 88 13.1720 2.3 0.5266 2.2 0.96 2727.2 49.9 2692.1 22.0 2665.8 10.8 2665.8 10.8 CM 67 13.0276 2.6 0.5203 2.4 0.95 2700.3 53.2 2681.7 24.1 2667.6 13.8 2667.6 13.8 CM 110 12.6263 3.1 0.5042 3.1 0.98 2631.7 66.4 2652.2 29.6 2667.8 11.3 2667.8 11.3 CM 91 12.9599 2.8 0.5169 2.7 0.97 2686.0 58.6 2676.7 26.0 2669.7 11.4 2669.7 11.4 CM 40 12.6717 2.9 0.5049 2.8 0.97 2635.0 60.5 2655.6 27.2 2671.3 11.9 2671.3 11.9 CM 47 12.7197 2.9 0.5037 2.8 0.98 2629.6 61.3 2659.1 27.3 2681.6 9.7 2681.6 9.7 CM 86 13.2608 2.4 0.5246 2.3 0.96 2718.5 50.5 2698.4 22.4 2683.4 11.3 2683.4 11.3 CM 109 12.9843 2.8 0.5120 2.8 0.98 2665.0 60.2 2678.5 26.6 2688.7 9.8 2688.7 9.8 CM 59 13.0815 2.9 0.5157 2.8 0.97 2680.7 61.2 2685.5 27.1 2689.2 11.0 2689.2 11.0 CM 41 13.4689 2.6 0.5301 2.4 0.94 2742.0 54.7 2713.1 24.5 2691.7 14.2 2691.7 14.2 CM 55 13.4123 3.7 0.5244 3.6 0.98 2717.8 80.8 2709.1 35.0 2702.7 11.2 2702.7 11.2 CM 106 13.5341 2.6 0.5276 2.4 0.95 2731.3 54.0 2717.7 24.1 2707.5 13.1 2707.5 13.1 CM 58 13.6588 2.5 0.5323 2.4 0.96 2751.0 54.2 2726.3 23.7 2708.1 10.9 2708.1 10.9 CM 54 13.3085 3.0 0.5165 3.0 0.99 2684.2 65.8 2701.8 28.6 2715.0 7.6 2715.0 7.6 CM 7 13.1555 3.5 0.5071 3.4 0.98 2644.2 74.0 2690.9 32.8 2726.1 10.9 2726.1 10.9 CM 95 13.8982 2.8 0.5306 2.7 0.96 2743.9 59.8 2742.8 26.3 2742.0 12.2 2742.0 12.2 CM 99 13.4580 3.2 0.5120 3.1 0.97 2665.0 67.0 2712.3 29.9 2747.8 12.5 2747.8 12.5 CM 33 14.7035 2.4 0.5516 2.3 0.95 2832.0 53.5 2796.2 23.3 2770.6 12.1 2770.6 12.1 CM 21 22.0171 2.7 0.6450 2.6 0.97 3208.7 66.1 3184.5 26.2 3169.3 10.1 3169.3 10.1

Table 2. Blakely

Isotope ratios Apparent ages (Ma) Best age BL-18

Analysis ± ± error ± ± ± ± 207Pb/235U* 206Pb/238U 206Pb/238U 207Pb/235U 206Pb/207Pb (%) (%) corr. (Ma) (Ma) (Ma) (Ma) (Ma)

BL 101 1.7021 2.1 0.1718 2.0 0.93 1022.2 18.6 1009.3 13.5 981.6 15.7 981.6 15.7 BL 12 1.6415 2.5 0.1650 2.5 0.97 984.7 22.5 986.3 16.0 989.7 12.9 989.7 12.9 BL 105 1.6903 2.3 0.1695 2.2 0.96 1009.3 20.5 1004.9 14.7 995.3 13.5 995.3 13.5 BL 62 1.7036 3.8 0.1708 3.7 0.96 1016.4 34.4 1009.9 24.5 995.7 22.8 995.7 22.8 BL 23 1.7215 2.6 0.1718 2.5 0.96 1022.2 23.9 1016.6 16.9 1004.4 15.0 1004.4 15.0 BL 28 1.6945 2.5 0.1691 2.4 0.97 1007.2 22.3 1006.5 15.8 1004.9 12.6 1004.9 12.6 BL 48 1.6741 2.3 0.1670 2.2 0.95 995.8 20.0 998.7 14.5 1005.2 14.3 1005.2 14.3 BL 14 1.7010 1.9 0.1697 1.7 0.92 1010.4 15.9 1008.9 11.9 1005.6 15.0 1005.6 15.0 BL 75 1.7214 2.9 0.1709 2.8 0.96 1017.1 26.1 1016.5 18.5 1015.3 15.8 1015.3 15.8 BL 76 1.7236 2.7 0.1702 2.5 0.93 1013.3 23.7 1017.4 17.4 1026.1 19.8 1026.1 19.8 BL 35 1.8215 3.0 0.1799 2.8 0.96 1066.2 28.0 1053.2 19.5 1026.5 17.5 1026.5 17.5 BL 104 1.7778 2.4 0.1755 2.3 0.95 1042.5 22.3 1037.4 15.8 1026.5 14.8 1026.5 14.8 BL 82 1.7315 2.1 0.1709 2.0 0.96 1017.0 18.9 1020.3 13.5 1027.4 11.8 1027.4 11.8 BL 3 1.7519 2.7 0.1720 2.6 0.97 1023.3 24.5 1027.9 17.2 1037.7 12.1 1037.7 12.1 BL 72 1.8499 2.3 0.1815 2.2 0.94 1075.3 21.5 1063.4 15.2 1039.0 15.7 1039.0 15.7 BL 1 1.8629 3.0 0.1827 2.9 0.96 1081.5 28.4 1068.0 19.6 1040.5 15.9 1040.5 15.9 BL 47 1.7756 2.5 0.1738 2.4 0.96 1033.3 23.3 1036.6 16.5 1043.5 14.2 1043.5 14.2 BL 100 1.7715 1.9 0.1732 1.8 0.92 1029.6 17.0 1035.1 12.7 1046.7 15.9 1046.7 15.9 BL 70 1.8135 3.8 0.1771 3.7 0.97 1050.9 35.5 1050.4 24.7 1049.3 18.7 1049.3 18.7

BL 97 1.7799 3.1 0.1736 2.9 0.96 1032.1 28.1 1038.1 19.9 1051.0 17.2 1051.0 17.2 BL 39 1.7639 3.3 0.1717 3.3 0.97 1021.7 30.8 1032.3 21.7 1054.9 15.7 1054.9 15.7 BL 51 1.8464 2.8 0.1794 2.7 0.96 1063.6 26.3 1062.1 18.5 1059.0 16.6 1059.0 16.6 BL 53 1.9430 4.4 0.1884 4.2 0.96 1112.8 43.2 1096.0 29.4 1062.8 24.0 1062.8 24.0 BL 31 1.8864 2.0 0.1828 1.9 0.93 1082.0 18.7 1076.3 13.4 1064.8 14.6 1064.8 14.6 BL 61 1.8109 4.2 0.1754 4.0 0.97 1042.0 39.0 1049.4 27.3 1064.9 19.8 1064.9 19.8 BL 5 1.8686 2.6 0.1809 2.5 0.94 1071.7 24.2 1070.0 17.3 1066.7 18.1 1066.7 18.1 BL 59 1.9007 2.9 0.1840 2.8 0.95 1088.6 27.7 1081.3 19.4 1066.8 18.4 1066.8 18.4 BL 43 1.8412 3.9 0.1780 3.8 0.98 1056.3 37.4 1060.3 25.9 1068.5 16.9 1068.5 16.9 BL 34 1.8560 2.6 0.1792 2.6 0.97 1062.7 25.1 1065.6 17.5 1071.4 13.4 1071.4 13.4 BL 50 1.8540 3.3 0.1786 3.1 0.94 1059.5 30.0 1064.9 21.5 1075.9 21.4 1075.9 21.4 BL 99 1.8495 1.7 0.1782 1.6 0.92 1057.0 15.3 1063.2 11.3 1076.1 13.3 1076.1 13.3 BL 19 1.8752 2.5 0.1805 2.4 0.97 1069.5 23.5 1072.4 16.3 1078.3 12.2 1078.3 12.2 BL 90 1.8335 2.2 0.1762 2.1 0.94 1046.4 19.9 1057.5 14.5 1080.5 15.7 1080.5 15.7 BL 57 1.9140 2.2 0.1835 2.1 0.94 1086.0 20.8 1086.0 14.8 1085.9 15.4 1085.9 15.4 BL 42 1.8477 2.8 0.1770 2.7 0.96 1050.8 26.3 1062.6 18.5 1086.9 14.8 1086.9 14.8 BL 93 1.8400 2.9 0.1755 2.8 0.97 1042.5 26.6 1059.9 18.8 1095.9 14.2 1095.9 14.2 BL 85 1.9181 3.9 0.1827 3.7 0.95 1081.6 37.1 1087.4 26.1 1099.0 24.3 1099.0 24.3 BL 110 1.9330 2.3 0.1840 2.2 0.96 1088.7 22.2 1092.6 15.4 1100.3 12.5 1100.3 12.5 BL 36 1.9436 2.6 0.1850 2.5 0.96 1094.1 25.1 1096.3 17.5 1100.5 14.5 1100.5 14.5 BL 27 1.8546 2.5 0.1765 2.4 0.94 1047.7 22.9 1065.1 16.5 1100.9 16.7 1100.9 16.7 BL 16 2.0569 4.2 0.1955 4.1 0.98 1151.1 43.1 1134.6 28.5 1103.2 16.8 1103.2 16.8 BL 21 1.8310 2.5 0.1722 2.4 0.95 1024.0 22.8 1056.6 16.6 1124.7 15.7 1124.7 15.7 BL 66 1.9802 2.7 0.1855 2.6 0.95 1097.2 26.1 1108.8 18.3 1131.5 16.7 1131.5 16.7 BL 102 2.0827 2.4 0.1946 2.3 0.95 1146.3 23.9 1143.1 16.4 1137.1 14.6 1137.1 14.6 BL 7 2.1283 2.4 0.1988 2.3 0.95 1168.7 24.3 1158.0 16.4 1138.2 14.2 1138.2 14.2 BL 54 2.0327 4.1 0.1896 3.9 0.96 1119.4 40.6 1126.5 28.0 1140.3 23.1 1140.3 23.1 BL 8 2.1301 2.9 0.1972 2.8 0.97 1160.4 29.8 1158.6 20.1 1155.3 14.6 1155.3 14.6 BL 49 1.9217 2.4 0.1765 2.2 0.92 1047.7 21.1 1088.7 15.8 1171.6 18.2 1171.6 18.2

BL 64 2.2331 2.4 0.2047 2.4 0.97 1200.6 25.9 1191.5 17.1 1175.0 11.8 1175.0 11.8 BL 4 2.1729 3.2 0.1986 3.1 0.97 1167.7 32.9 1172.4 22.0 1181.1 14.4 1181.1 14.4 BL 55 1.9295 4.4 0.1763 4.3 0.98 1046.7 41.1 1091.4 29.2 1181.6 18.8 1181.6 18.8 BL 56 2.1546 2.4 0.1964 2.3 0.95 1156.2 24.0 1166.5 16.6 1185.8 15.5 1185.8 15.5 BL 38 2.2802 2.0 0.2059 1.8 0.90 1206.7 19.6 1206.2 14.0 1205.2 17.2 1205.2 17.2 BL 41 2.2311 3.2 0.2012 3.1 0.96 1182.0 33.2 1190.9 22.4 1207.1 17.2 1207.1 17.2 BL 20 2.1863 2.8 0.1951 2.6 0.93 1148.7 27.3 1176.7 19.4 1228.5 19.6 1228.5 19.6 BL 33 2.4228 2.7 0.2152 2.7 0.97 1256.6 30.3 1249.4 19.6 1237.0 12.0 1237.0 12.0 BL 24 2.4164 3.6 0.2098 3.4 0.95 1227.8 37.8 1247.5 25.5 1281.6 21.6 1281.6 21.6 BL 65 2.6808 3.1 0.2260 2.9 0.96 1313.6 35.0 1323.2 22.6 1338.7 16.3 1338.7 16.3 BL 26 2.7298 2.4 0.2295 2.3 0.96 1331.7 27.2 1336.6 17.6 1344.5 13.4 1344.5 13.4 BL 60 2.7580 2.9 0.2308 2.8 0.97 1338.7 34.0 1344.2 21.6 1353.0 13.4 1353.0 13.4 BL 40 2.7124 3.0 0.2265 2.9 0.96 1316.4 34.6 1331.9 22.5 1356.9 16.2 1356.9 16.2 BL 13 2.7236 2.6 0.2274 2.5 0.96 1320.8 29.7 1334.9 19.2 1357.7 13.4 1357.7 13.4 BL 6 2.8034 2.4 0.2339 2.3 0.93 1355.2 27.6 1356.4 18.1 1358.5 16.6 1358.5 16.6 BL 91 2.8860 2.4 0.2404 2.3 0.96 1388.7 29.2 1378.3 18.4 1362.2 13.3 1362.2 13.3 BL 32 2.8898 2.7 0.2402 2.6 0.95 1387.5 32.3 1379.3 20.5 1366.5 15.8 1366.5 15.8 BL 10 2.9073 3.2 0.2416 3.1 0.97 1394.9 38.9 1383.8 24.1 1366.7 14.5 1366.7 14.5 BL 83 2.9130 2.7 0.2393 2.6 0.96 1382.9 31.7 1385.3 20.1 1389.0 14.5 1389.0 14.5 BL 106 2.9153 1.8 0.2395 1.7 0.96 1383.9 21.7 1385.9 13.8 1389.0 10.3 1389.0 10.3 BL 9 2.8755 2.1 0.2362 2.0 0.95 1366.7 24.4 1375.5 15.8 1389.1 13.0 1389.1 13.0 BL 86 2.8483 2.9 0.2331 2.8 0.97 1350.9 33.9 1368.4 21.6 1395.7 13.9 1395.7 13.9 BL 15 3.0318 4.7 0.2467 4.6 0.99 1421.6 59.2 1415.7 35.9 1406.8 14.2 1406.8 14.2 BL 88 3.0162 2.9 0.2445 2.8 0.97 1409.8 35.7 1411.7 22.1 1414.6 12.9 1414.6 12.9 BL 81 3.1313 3.3 0.2509 3.3 0.98 1443.1 42.2 1440.4 25.7 1436.5 13.8 1436.5 13.8 BL 67 3.1171 2.1 0.2496 2.0 0.95 1436.4 25.2 1436.9 15.9 1437.7 12.9 1437.7 12.9 BL 103 2.9614 2.5 0.2370 2.5 0.97 1370.9 30.5 1397.8 19.3 1439.0 11.6 1439.0 11.6 BL 22 3.1218 2.6 0.2488 2.5 0.96 1432.3 31.5 1438.1 19.7 1446.6 13.9 1446.6 13.9 BL 92 3.1044 3.1 0.2473 3.0 0.96 1424.4 38.7 1433.8 24.2 1447.6 16.4 1447.6 16.4

BL 78 3.2008 2.5 0.2543 2.4 0.96 1460.7 31.5 1457.4 19.4 1452.5 13.6 1452.5 13.6 BL 68 3.2243 2.9 0.2561 2.8 0.96 1469.7 36.8 1463.0 22.6 1453.3 16.0 1453.3 16.0 BL 73 3.1030 3.3 0.2458 3.2 0.98 1416.5 40.4 1433.4 25.0 1458.6 13.8 1458.6 13.8 BL 87 3.1617 2.6 0.2499 2.6 0.97 1437.9 32.9 1447.9 20.2 1462.5 11.6 1462.5 11.6 BL 89 3.2859 2.8 0.2594 2.6 0.95 1486.7 35.1 1477.7 21.5 1464.8 15.7 1464.8 15.7 BL 107 3.1862 2.2 0.2511 2.1 0.96 1444.2 27.0 1453.8 16.7 1467.9 11.2 1467.9 11.2 BL 74 3.2843 3.7 0.2575 3.6 0.97 1476.9 47.1 1477.3 28.5 1477.9 15.5 1477.9 15.5 BL 96 3.2847 2.4 0.2550 2.3 0.96 1464.3 29.9 1477.4 18.5 1496.4 12.7 1496.4 12.7 BL 46 3.5907 3.7 0.2642 3.6 0.98 1511.5 48.7 1547.5 29.4 1596.9 15.1 1596.9 15.1 BL 17 3.8174 2.8 0.2778 2.8 0.97 1580.0 38.6 1596.4 22.7 1618.1 12.0 1618.1 12.0 BL 58 3.7868 3.6 0.2740 3.6 0.98 1560.9 49.5 1590.0 29.2 1628.7 12.6 1628.7 12.6 BL 69 3.9543 2.3 0.2858 2.3 0.96 1620.6 32.3 1624.9 19.0 1630.4 11.7 1630.4 11.7 BL 30 4.1049 2.2 0.2921 2.1 0.94 1651.8 30.2 1655.3 17.9 1659.6 13.3 1659.6 13.3 BL 95 4.1376 2.7 0.2923 2.6 0.96 1653.1 38.0 1661.8 22.3 1672.8 14.5 1672.8 14.5 BL 94 4.4830 2.3 0.3050 2.2 0.95 1716.1 32.5 1727.8 18.8 1742.1 12.4 1742.1 12.4 BL 44 10.2343 2.8 0.4265 2.6 0.95 2290.0 50.8 2456.2 25.6 2596.7 13.8 2596.7 13.8 BL 37 10.1195 2.0 0.4198 1.9 0.95 2259.7 36.1 2445.8 18.5 2604.3 10.8 2604.3 10.8 BL 108 12.2319 2.7 0.5001 2.6 0.95 2614.3 55.4 2622.4 25.4 2628.6 13.5 2628.6 13.5 BL 2 12.8345 3.0 0.5172 2.9 0.96 2687.4 63.9 2667.6 28.5 2652.6 13.6 2652.6 13.6 BL 71 12.9293 3.4 0.5171 3.3 0.98 2687.0 72.8 2674.5 32.0 2665.1 12.2 2665.1 12.2 BL 63 12.6310 3.4 0.5044 3.3 0.98 2632.5 71.8 2652.5 31.9 2667.9 10.8 2667.9 10.8 BL 98 13.0736 2.1 0.5189 2.0 0.96 2694.6 44.4 2685.0 19.7 2677.7 9.1 2677.7 9.1 BL 80 12.7471 2.2 0.5055 2.1 0.95 2637.3 45.4 2661.1 20.7 2679.3 11.0 2679.3 11.0 BL 45 13.2725 2.0 0.5231 1.9 0.94 2712.3 42.3 2699.2 19.3 2689.4 11.9 2689.4 11.9 BL 52 13.7807 3.1 0.5410 2.9 0.93 2787.8 65.0 2734.8 29.3 2695.8 18.8 2695.8 18.8 BL 25 13.3643 3.5 0.5244 3.4 0.98 2718.0 75.9 2705.7 33.0 2696.6 11.2 2696.6 11.2 BL 11 13.2296 2.9 0.5179 2.8 0.96 2690.1 61.2 2696.2 27.4 2700.7 13.6 2700.7 13.6 BL 84 13.1834 3.4 0.5160 3.3 0.98 2682.2 73.3 2692.9 32.2 2700.9 11.3 2700.9 11.3 BL 18 13.0802 2.8 0.5107 2.7 0.96 2659.6 58.0 2685.5 26.0 2705.0 12.0 2705.0 12.0

BL 79 13.0405 2.3 0.5087 2.2 0.96 2651.3 48.9 2682.6 22.1 2706.3 10.9 2706.3 10.9 BL 29 13.0511 2.6 0.5073 2.5 0.97 2645.2 54.5 2683.4 24.3 2712.2 9.6 2712.2 9.6

Table 3. Womble

Isotope ratios Apparent ages (Ma) Best age 23-WB

Analysis ± ± error ± ± ± ± 207Pb/235U 206Pb/238U 206Pb/238U 207Pb/235U 206Pb/207Pb (%) (%) corr. (Ma) (Ma) (Ma) (Ma) (Ma)

WB 104 2.0140 2.8 0.1913 2.7 0.96 1128.3 27.9 1120.3 19.1 1104.7 15.5 1104.7 15.5 WB 18 1.9990 2.6 0.1898 2.5 0.95 1120.4 25.8 1115.2 17.9 1105.0 16.8 1105.0 16.8 WB 13 2.0309 3.0 0.1927 2.8 0.96 1136.2 29.5 1125.9 20.1 1106.2 17.4 1106.2 17.4 WB 8 2.0701 4.1 0.1964 4.0 0.97 1155.7 42.7 1139.0 28.4 1107.2 19.3 1107.2 19.3 WB 29 2.0539 2.9 0.1948 2.8 0.97 1147.3 29.4 1133.6 19.8 1107.4 15.1 1107.4 15.1 WB 34 2.0370 3.4 0.1923 3.2 0.96 1133.8 33.4 1128.0 22.9 1116.7 19.8 1116.7 19.8 WB 45 2.0177 3.1 0.1904 3.1 0.97 1123.7 31.5 1121.5 21.3 1117.3 14.3 1117.3 14.3 WB 52 2.0489 3.2 0.1932 3.1 0.97 1138.9 32.2 1131.9 21.7 1118.6 15.8 1118.6 15.8 WB 2 2.0666 2.6 0.1943 2.5 0.96 1144.8 26.2 1137.8 17.8 1124.5 13.9 1124.5 13.9 WB 70 2.0727 2.6 0.1948 2.4 0.93 1147.4 25.1 1139.8 17.5 1125.4 18.1 1125.4 18.1 WB 68 2.0220 2.7 0.1897 2.5 0.96 1119.8 26.2 1122.9 18.1 1129.1 15.6 1129.1 15.6 WB 35 2.1303 3.7 0.1997 3.6 0.97 1173.8 38.1 1158.7 25.3 1130.6 17.4 1130.6 17.4 WB 71 2.0878 3.1 0.1956 3.0 0.96 1151.9 31.9 1144.8 21.6 1131.4 17.8 1131.4 17.8 WB 31 2.0609 3.0 0.1928 2.9 0.95 1136.3 30.2 1135.9 20.8 1135.2 18.6 1135.2 18.6

WB 38 2.0459 2.9 0.1911 2.8 0.97 1127.2 29.2 1130.9 19.8 1138.1 14.1 1138.1 14.1 WB 42 2.1187 2.0 0.1975 1.9 0.94 1162.0 20.2 1154.9 13.9 1141.6 13.6 1141.6 13.6 WB 82 2.0427 2.9 0.1901 2.7 0.95 1122.0 28.1 1129.9 19.6 1144.9 18.6 1144.9 18.6 WB 32 2.0601 3.1 0.1915 3.1 0.97 1129.3 31.6 1135.7 21.5 1147.8 15.2 1147.8 15.2 WB 33 2.0469 3.9 0.1902 3.7 0.97 1122.4 38.4 1131.3 26.3 1148.3 19.8 1148.3 19.8 WB 43 2.0759 3.1 0.1928 3.0 0.96 1136.8 31.3 1140.9 21.5 1148.7 17.5 1148.7 17.5 WB 96 2.0794 3.8 0.1921 3.6 0.95 1132.8 37.2 1142.0 25.9 1159.7 23.8 1159.7 23.8 WB 110 2.0874 3.6 0.1901 3.4 0.94 1121.8 34.8 1144.7 24.6 1188.3 23.5 1188.3 23.5 WB 99 2.2276 3.9 0.2028 3.8 0.97 1190.6 40.9 1189.8 27.2 1188.3 19.3 1188.3 19.3 WB 40 2.3680 2.2 0.2011 2.1 0.95 1181.2 22.6 1233.0 15.7 1324.8 13.1 1324.8 13.1 WB 39 2.8519 3.4 0.2412 3.3 0.98 1393.0 41.8 1369.3 25.6 1332.4 13.4 1332.4 13.4 WB 4 2.8655 3.2 0.2423 3.1 0.97 1398.6 38.7 1372.9 23.8 1333.0 13.7 1333.0 13.7 WB 26 2.8592 3.9 0.2409 3.7 0.96 1391.2 46.4 1371.2 29.0 1340.3 20.7 1340.3 20.7 WB 67 2.8065 2.6 0.2360 2.5 0.95 1365.9 30.3 1357.3 19.4 1343.7 15.5 1343.7 15.5 WB 22 2.8865 3.6 0.2425 3.4 0.97 1399.5 43.4 1378.4 26.8 1345.8 17.0 1345.8 17.0 WB 62 2.7927 3.6 0.2339 3.5 0.97 1355.1 42.7 1353.6 26.8 1351.2 15.7 1351.2 15.7 WB 78 2.8729 2.5 0.2406 2.4 0.95 1389.9 30.1 1374.8 19.1 1351.4 15.0 1351.4 15.0 WB 49 2.8445 3.5 0.2382 3.4 0.97 1377.5 42.4 1367.3 26.4 1351.5 15.5 1351.5 15.5 WB 25 2.9020 3.1 0.2425 3.0 0.96 1399.8 37.8 1382.4 23.5 1355.7 16.1 1355.7 16.1 WB 97 2.8792 3.4 0.2406 3.2 0.95 1389.7 40.0 1376.5 25.3 1356.1 19.2 1356.1 19.2 WB 7 2.8836 4.2 0.2408 4.1 0.98 1391.0 51.9 1377.6 32.0 1356.9 16.9 1356.9 16.9 WB 72 2.8705 2.5 0.2396 2.4 0.97 1384.8 30.3 1374.2 18.9 1357.7 12.2 1357.7 12.2 WB 44 2.8422 2.8 0.2373 2.7 0.96 1372.5 33.2 1366.8 20.9 1357.8 14.1 1357.8 14.1 WB 92 2.6856 2.1 0.2242 2.0 0.96 1304.0 23.3 1324.5 15.2 1357.9 10.8 1357.9 10.8 WB 15 2.8365 3.3 0.2367 3.2 0.97 1369.7 38.9 1365.2 24.4 1358.2 15.4 1358.2 15.4 WB 86 2.9288 2.5 0.2444 2.4 0.95 1409.6 30.3 1389.4 19.0 1358.5 14.9 1358.5 14.9 WB 84 2.8974 2.3 0.2417 2.2 0.95 1395.5 27.5 1381.2 17.5 1359.1 14.5 1359.1 14.5 WB 80 2.6525 3.0 0.2212 3.0 0.98 1288.0 34.6 1315.3 22.4 1360.1 12.8 1360.1 12.8 WB 73 2.8954 3.0 0.2410 2.9 0.96 1392.1 35.8 1380.7 22.6 1363.1 16.7 1363.1 16.7

WB 109 2.8090 2.7 0.2337 2.6 0.96 1354.0 31.7 1357.9 20.3 1364.1 15.3 1364.1 15.3 WB 75 2.8492 2.9 0.2370 2.8 0.97 1371.1 34.5 1368.6 21.8 1364.6 14.6 1364.6 14.6 WB 41 2.8232 2.7 0.2348 2.6 0.95 1359.5 31.7 1361.7 20.5 1365.1 17.2 1365.1 17.2 WB 81 2.8714 3.1 0.2388 3.0 0.95 1380.3 37.2 1374.4 23.7 1365.3 18.5 1365.3 18.5 WB 55 2.8412 2.5 0.2363 2.5 0.98 1367.2 30.3 1366.5 18.9 1365.3 10.6 1365.3 10.6 WB 53 2.9430 3.6 0.2446 3.5 0.97 1410.6 44.9 1393.0 27.5 1366.2 15.6 1366.2 15.6 WB 17 2.9151 2.5 0.2423 2.3 0.94 1398.5 29.4 1385.8 18.7 1366.3 15.7 1366.3 15.7 WB 51 2.8343 2.8 0.2354 2.7 0.97 1362.8 32.8 1364.7 20.7 1367.5 12.8 1367.5 12.8 WB 83 2.9188 3.3 0.2424 3.2 0.96 1399.2 39.9 1386.8 25.1 1367.7 18.7 1367.7 18.7 WB 79 2.9040 2.9 0.2411 2.8 0.95 1392.6 35.0 1383.0 22.3 1368.0 17.8 1368.0 17.8 WB 19 2.9556 3.4 0.2454 3.3 0.98 1414.6 41.7 1396.3 25.5 1368.3 14.3 1368.3 14.3 WB 74 2.9398 3.0 0.2440 2.9 0.96 1407.4 36.8 1392.2 23.0 1369.0 16.4 1369.0 16.4 WB 94 2.8781 3.5 0.2388 3.4 0.97 1380.6 41.9 1376.2 26.2 1369.3 16.3 1369.3 16.3 WB 63 2.9023 4.3 0.2407 4.2 0.97 1390.4 52.1 1382.5 32.4 1370.3 19.9 1370.3 19.9 WB 23 2.8109 3.4 0.2331 3.3 0.97 1350.8 40.5 1358.4 25.5 1370.4 14.6 1370.4 14.6 WB 76 2.9354 3.1 0.2434 3.0 0.97 1404.5 38.3 1391.1 23.7 1370.5 14.9 1370.5 14.9 WB 6 2.8840 3.4 0.2390 3.3 0.97 1381.5 41.4 1377.7 25.9 1371.9 16.1 1371.9 16.1 WB 90 2.8494 3.3 0.2361 3.2 0.97 1366.4 38.9 1368.7 24.5 1372.1 15.7 1372.1 15.7 WB 91 2.9334 4.9 0.2429 4.9 0.99 1402.0 61.6 1390.6 37.5 1373.1 15.0 1373.1 15.0 WB 95 2.9110 2.9 0.2410 2.8 0.97 1391.7 35.6 1384.8 22.2 1374.0 13.7 1374.0 13.7 WB 98 2.8803 2.8 0.2384 2.7 0.96 1378.4 33.8 1376.8 21.3 1374.2 14.4 1374.2 14.4 WB 59 2.8403 3.2 0.2350 3.2 0.98 1360.9 38.9 1366.3 24.3 1374.6 12.5 1374.6 12.5 WB 36 2.8455 3.4 0.2354 3.3 0.96 1363.0 40.3 1367.6 25.7 1374.8 18.4 1374.8 18.4 WB 3 2.8854 2.3 0.2388 2.3 0.97 1380.2 28.3 1378.1 17.7 1374.9 10.7 1374.9 10.7 WB 12 2.9283 3.2 0.2423 3.1 0.96 1398.5 38.6 1389.3 24.3 1375.1 18.1 1375.1 18.1 WB 64 2.9607 2.5 0.2450 2.4 0.95 1412.4 30.1 1397.6 19.0 1375.1 15.6 1375.1 15.6 WB 101 2.8918 2.9 0.2391 2.7 0.96 1382.3 34.2 1379.8 21.7 1375.9 15.9 1375.9 15.9 WB 66 2.9226 3.6 0.2413 3.5 0.96 1393.6 43.6 1387.8 27.4 1378.9 18.9 1378.9 18.9 WB 20 2.8666 3.8 0.2365 3.7 0.96 1368.5 45.1 1373.2 28.5 1380.5 19.4 1380.5 19.4

WB 57 2.7874 3.5 0.2299 3.4 0.97 1334.1 40.6 1352.2 26.0 1380.9 16.6 1380.9 16.6 WB 88 2.9730 3.7 0.2452 3.5 0.95 1413.7 44.3 1400.7 28.0 1381.1 23.2 1381.1 23.2 WB 46 2.9458 2.8 0.2428 2.6 0.96 1401.2 33.3 1393.8 21.0 1382.4 15.6 1382.4 15.6 WB 9 2.8893 2.7 0.2381 2.6 0.96 1376.6 32.2 1379.1 20.4 1383.0 14.5 1383.0 14.5 WB 28 2.9201 3.9 0.2405 3.7 0.97 1389.2 46.6 1387.1 29.2 1384.0 18.6 1384.0 18.6 WB 107 2.8421 2.2 0.2337 2.0 0.92 1354.0 24.2 1366.7 16.2 1386.7 16.1 1386.7 16.1 WB 27 2.9294 2.3 0.2408 2.3 0.97 1390.6 28.2 1389.5 17.6 1387.8 11.1 1387.8 11.1 WB 85 2.7503 3.9 0.2256 3.7 0.96 1311.4 44.1 1342.2 28.9 1391.6 21.1 1391.6 21.1 WB 102 2.9696 3.1 0.2430 3.0 0.97 1402.3 37.7 1399.9 23.5 1396.1 14.9 1396.1 14.9 WB 56 2.9581 3.0 0.2419 2.8 0.93 1396.8 34.7 1396.9 22.6 1397.1 21.4 1397.1 21.4 WB 16 2.9628 3.3 0.2423 3.2 0.97 1398.7 40.9 1398.1 25.4 1397.2 14.9 1397.2 14.9 WB 50 2.9016 4.0 0.2372 3.9 0.96 1372.1 47.6 1382.3 30.3 1398.1 21.7 1398.1 21.7 WB 77 2.8948 2.8 0.2366 2.7 0.95 1368.8 33.2 1380.5 21.5 1398.7 17.4 1398.7 17.4 WB 47 2.9236 2.9 0.2386 2.8 0.97 1379.2 35.0 1388.0 21.9 1401.7 13.3 1401.7 13.3 WB 108 2.9144 3.5 0.2369 3.4 0.96 1370.5 41.4 1385.7 26.3 1409.1 17.7 1409.1 17.7 WB 69 3.0311 4.4 0.2461 4.1 0.94 1418.5 52.2 1415.5 33.3 1410.9 28.2 1410.9 28.2 WB 87 2.8377 3.2 0.2303 3.1 0.95 1336.3 37.0 1365.6 24.1 1411.7 18.2 1411.7 18.2 WB 105 3.0090 3.1 0.2438 2.9 0.94 1406.2 37.2 1409.9 23.9 1415.5 20.5 1415.5 20.5 WB 93 2.8902 3.0 0.2335 2.8 0.93 1352.9 33.9 1379.4 22.4 1420.5 20.4 1420.5 20.4 WB 10 2.9461 3.2 0.2375 2.9 0.92 1373.5 36.0 1393.9 24.1 1425.2 24.2 1425.2 24.2 WB 100 3.1965 2.2 0.2564 2.1 0.96 1471.4 27.8 1456.3 17.1 1434.3 12.3 1434.3 12.3 WB 65 3.0799 2.9 0.2462 2.7 0.93 1418.9 34.7 1427.7 22.4 1440.8 19.9 1440.8 19.9 WB 48 3.1819 2.8 0.2486 2.5 0.88 1431.5 31.5 1452.8 21.4 1484.1 24.7 1484.1 24.7 WB 5 3.2088 2.7 0.2458 2.5 0.91 1417.0 31.7 1459.3 21.2 1521.4 21.4 1521.4 21.4 WB 61 3.2897 4.2 0.2438 3.4 0.81 1406.4 42.6 1478.6 32.5 1583.8 46.0 1583.8 46.0 WB 60 3.7273 2.4 0.2702 2.3 0.97 1542.0 31.8 1577.2 19.2 1624.6 11.4 1624.6 11.4 WB 24 4.0517 3.6 0.2891 3.5 0.98 1636.9 51.0 1644.6 29.3 1654.6 13.3 1654.6 13.3 WB 21 4.6102 2.3 0.3143 2.2 0.93 1762.0 33.5 1751.1 19.4 1738.1 15.3 1738.1 15.3 WB 37 3.7995 3.2 0.2554 2.6 0.81 1466.5 33.8 1592.6 25.6 1763.9 34.2 1763.9 34.2

Table 4. Polk Creek

Isotope ratios Apparent ages (Ma) Best age PC-14

Analysis ± ± error ± ± ± ± 207Pb/235U 206Pb/238U 206Pb/238U 207Pb/235U 206Pb/207Pb (%) (%) corr. (Ma) (Ma) (Ma) (Ma) (Ma)

PC 91 1.6867 2.4 0.1707 2.3 0.95 1015.7 21.7 1003.5 15.6 977.0 16.3 977.0 16.3 PC 63 1.6957 3.2 0.1705 3.0 0.95 1015.1 28.3 1006.9 20.2 989.1 19.7 989.1 19.7 PC 69 1.6721 3.1 0.1676 2.9 0.94 998.9 26.9 998.0 19.5 996.1 20.5 996.1 20.5 PC 107 1.6854 3.0 0.1689 2.8 0.95 1006.0 26.1 1003.0 18.8 996.5 18.9 996.5 18.9 PC 54 1.7221 2.9 0.1723 2.7 0.95 1024.9 26.0 1016.8 18.6 999.4 18.4 999.4 18.4 PC 103 1.6834 2.0 0.1683 1.9 0.94 1002.6 17.5 1002.3 12.7 1001.6 13.5 1001.6 13.5 PC 61 1.7355 2.6 0.1734 2.4 0.95 1030.7 23.3 1021.8 16.5 1002.9 15.8 1002.9 15.8 PC 17 1.7186 2.3 0.1715 2.2 0.94 1020.6 20.7 1015.5 14.9 1004.6 15.8 1004.6 15.8 PC 14 1.6869 2.2 0.1683 2.1 0.95 1002.6 19.5 1003.6 14.1 1005.9 14.2 1005.9 14.2 PC 12 1.7053 2.1 0.1695 1.9 0.93 1009.4 17.9 1010.5 13.1 1013.0 14.9 1013.0 14.9 PC 5 1.7643 2.1 0.1750 2.1 0.96 1039.6 19.7 1032.4 13.9 1017.2 12.4 1017.2 12.4 PC 60 1.6936 2.2 0.1679 2.1 0.96 1000.5 19.4 1006.1 13.9 1018.4 12.1 1018.4 12.1 PC 68 1.7271 2.7 0.1711 2.6 0.94 1018.3 24.2 1018.7 17.6 1019.3 18.7 1019.3 18.7 PC 36 1.7388 2.7 0.1718 2.6 0.95 1021.8 24.3 1023.0 17.4 1025.5 16.2 1025.5 16.2 PC 106 1.7425 2.3 0.1719 2.1 0.93 1022.8 20.2 1024.4 14.8 1027.8 16.8 1027.8 16.8 PC 48 1.6926 1.8 0.1670 1.7 0.94 995.6 16.0 1005.7 11.7 1028.0 12.7 1028.0 12.7 PC 53 1.7315 2.6 0.1707 2.5 0.95 1015.8 23.7 1020.3 17.0 1029.9 16.5 1029.9 16.5

PC 77 1.7339 3.0 0.1709 2.9 0.98 1017.2 27.2 1021.2 19.0 1029.9 12.7 1029.9 12.7 PC 44 1.8252 2.6 0.1799 2.5 0.96 1066.4 25.0 1054.6 17.3 1030.1 14.3 1030.1 14.3 PC 57 1.6834 2.2 0.1658 2.1 0.95 989.2 19.1 1002.3 13.9 1031.0 13.3 1031.0 13.3 PC 59 1.7969 2.6 0.1769 2.4 0.94 1049.8 23.2 1044.3 16.7 1032.9 18.3 1032.9 18.3 PC 71 1.7348 2.3 0.1706 2.2 0.95 1015.4 20.9 1021.5 15.1 1034.8 14.7 1034.8 14.7 PC 82 1.8085 2.9 0.1778 2.8 0.94 1054.8 27.0 1048.6 19.2 1035.6 19.7 1035.6 19.7 PC 85 1.7981 2.6 0.1766 2.4 0.94 1048.6 23.5 1044.8 16.8 1036.6 17.1 1036.6 17.1 PC 87 1.7123 3.4 0.1676 3.4 0.97 999.1 31.0 1013.1 22.1 1043.5 15.9 1043.5 15.9 PC 93 1.7245 2.5 0.1687 2.3 0.95 1005.2 21.7 1017.7 15.8 1044.6 15.9 1044.6 15.9 PC 11 1.7826 2.7 0.1744 2.6 0.94 1036.3 24.8 1039.1 17.9 1045.0 18.8 1045.0 18.8 PC 1 1.8207 3.2 0.1778 3.1 0.97 1054.9 30.4 1052.9 21.2 1048.9 16.2 1048.9 16.2 PC 84 1.7034 2.0 0.1663 1.9 0.95 991.9 17.1 1009.8 12.5 1049.0 11.9 1049.0 11.9 PC 19 1.8125 2.9 0.1769 2.8 0.95 1049.8 26.9 1050.0 19.1 1050.3 18.7 1050.3 18.7 PC 40 1.8064 2.9 0.1763 2.7 0.94 1046.6 26.1 1047.8 18.7 1050.3 18.9 1050.3 18.9 PC 97 1.7677 2.3 0.1725 2.3 0.97 1025.8 21.4 1033.7 15.1 1050.5 12.0 1050.5 12.0 PC 110 1.8923 3.3 0.1843 3.1 0.93 1090.4 31.1 1078.4 22.2 1054.3 24.6 1054.3 24.6 PC 98 1.7695 3.2 0.1722 3.1 0.97 1024.3 29.1 1034.3 20.6 1055.5 16.5 1055.5 16.5 PC 37 1.8037 2.6 0.1755 2.4 0.93 1042.5 23.4 1046.8 17.0 1055.8 18.9 1055.8 18.9 PC 95 1.8370 2.7 0.1788 2.6 0.94 1060.2 25.3 1058.8 18.0 1056.0 18.1 1056.0 18.1 PC 20 1.7609 2.7 0.1713 2.5 0.94 1019.3 23.7 1031.2 17.3 1056.6 18.8 1056.6 18.8 PC 43 1.8376 2.3 0.1786 2.1 0.94 1059.6 20.8 1059.0 14.8 1057.9 14.9 1057.9 14.9 PC 76 1.7239 3.0 0.1674 2.8 0.95 997.6 26.0 1017.5 19.0 1060.5 18.2 1060.5 18.2 PC 65 1.8874 2.6 0.1832 2.5 0.95 1084.4 24.5 1076.7 17.1 1061.0 15.8 1061.0 15.8 PC 99 1.8565 2.8 0.1800 2.7 0.96 1066.8 26.4 1065.7 18.4 1063.4 16.0 1063.4 16.0 PC 23 1.8385 2.5 0.1782 2.4 0.96 1057.3 23.2 1059.3 16.3 1063.5 14.5 1063.5 14.5 PC 100 1.8369 3.0 0.1779 2.9 0.98 1055.7 28.2 1058.8 19.5 1065.1 12.7 1065.1 12.7 PC 74 1.7133 2.3 0.1657 2.2 0.95 988.5 19.9 1013.5 14.7 1068.0 14.6 1068.0 14.6 PC 73 1.8807 2.2 0.1817 2.1 0.94 1076.1 20.8 1074.3 14.8 1070.7 14.8 1070.7 14.8 PC 80 1.8595 2.3 0.1791 2.1 0.94 1061.8 20.9 1066.8 15.0 1077.1 15.7 1077.1 15.7

PC 72 1.8156 2.5 0.1748 2.4 0.96 1038.7 22.7 1051.1 16.2 1077.1 14.7 1077.1 14.7 PC 30 1.8434 2.6 0.1774 2.4 0.95 1052.8 23.7 1061.1 16.9 1078.2 16.6 1078.2 16.6 PC 86 1.8656 2.5 0.1795 2.3 0.94 1064.3 22.7 1069.0 16.3 1078.4 16.7 1078.4 16.7 PC 33 1.8239 2.7 0.1753 2.6 0.96 1041.1 24.6 1054.1 17.5 1081.2 15.0 1081.2 15.0 PC 42 1.8812 2.0 0.1800 1.9 0.94 1066.7 18.8 1074.5 13.5 1090.2 14.5 1090.2 14.5 PC 22 1.8605 2.6 0.1777 2.5 0.96 1054.3 23.9 1067.2 16.8 1093.7 14.0 1093.7 14.0 PC 62 1.9112 3.7 0.1823 3.6 0.97 1079.3 35.5 1085.0 24.5 1096.5 17.3 1096.5 17.3 PC 108 1.9700 2.7 0.1875 2.6 0.96 1107.9 26.5 1105.3 18.2 1100.1 14.9 1100.1 14.9 PC 38 1.9228 2.9 0.1827 2.8 0.96 1081.5 27.6 1089.0 19.3 1104.1 16.0 1104.1 16.0 PC 7 1.9252 3.2 0.1826 3.1 0.97 1080.9 30.8 1089.9 21.3 1107.8 16.0 1107.8 16.0 PC 9 2.0584 2.7 0.1939 2.6 0.94 1142.3 26.8 1135.1 18.7 1121.3 19.0 1121.3 19.0 PC 26 1.9078 2.7 0.1795 2.6 0.96 1064.3 25.2 1083.8 17.9 1123.3 15.3 1123.3 15.3 PC 39 2.0703 3.7 0.1934 3.5 0.96 1139.8 36.9 1139.0 25.1 1137.6 19.4 1137.6 19.4 PC 81 2.0687 2.6 0.1932 2.5 0.96 1138.7 26.1 1138.5 17.9 1138.2 14.6 1138.2 14.6 PC 28 2.0755 2.7 0.1932 2.5 0.95 1138.8 26.6 1140.8 18.4 1144.5 17.0 1144.5 17.0 PC 79 2.1566 3.1 0.2006 3.0 0.97 1178.5 31.9 1167.2 21.3 1146.2 15.8 1146.2 15.8 PC 45 1.9817 2.7 0.1841 2.6 0.95 1089.5 26.0 1109.3 18.5 1148.4 17.2 1148.4 17.2 PC 89 2.0562 2.7 0.1910 2.6 0.97 1126.6 27.0 1134.4 18.4 1149.3 12.6 1149.3 12.6 PC 75 2.1284 2.9 0.1972 2.7 0.94 1160.3 28.9 1158.1 20.0 1153.8 19.3 1153.8 19.3 PC 66 2.0756 3.2 0.1923 3.0 0.96 1133.6 31.6 1140.8 21.7 1154.5 17.4 1154.5 17.4 PC 10 2.0873 2.3 0.1933 2.2 0.96 1139.3 22.6 1144.6 15.5 1154.8 12.9 1154.8 12.9 PC 49 2.0862 2.6 0.1928 2.5 0.95 1136.6 26.0 1144.3 18.1 1158.9 16.7 1158.9 16.7 PC 18 2.1329 2.9 0.1968 2.8 0.97 1158.3 30.0 1159.5 20.2 1161.7 14.7 1161.7 14.7 PC 3 2.0324 3.6 0.1870 3.3 0.93 1105.3 33.8 1126.4 24.4 1167.3 26.5 1167.3 26.5 PC 88 2.1595 3.0 0.1986 2.9 0.96 1167.9 30.6 1168.1 20.7 1168.4 16.9 1168.4 16.9 PC 31 2.1656 2.2 0.1988 2.1 0.97 1169.1 22.6 1170.1 15.2 1171.9 11.0 1171.9 11.0 PC 96 2.2006 2.5 0.2010 2.4 0.96 1180.6 25.7 1181.2 17.4 1182.4 14.5 1182.4 14.5 PC 24 2.1948 3.4 0.1999 3.3 0.95 1174.6 35.1 1179.4 24.0 1188.2 21.1 1188.2 21.1 PC 64 2.1685 5.2 0.1955 5.0 0.96 1151.3 52.7 1171.0 36.0 1207.6 26.9 1207.6 26.9

PC 55 2.2441 3.1 0.2021 3.0 0.96 1186.4 32.7 1194.9 22.1 1210.4 17.6 1210.4 17.6 PC 6 2.4118 2.8 0.2169 2.7 0.97 1265.6 31.4 1246.1 20.2 1212.6 13.1 1212.6 13.1 PC 90 2.2544 2.6 0.2016 2.4 0.96 1183.7 26.5 1198.2 18.0 1224.3 14.3 1224.3 14.3 PC 104 2.3554 2.2 0.2097 2.1 0.93 1227.1 23.2 1229.2 15.9 1232.9 16.4 1232.9 16.4 PC 35 2.3584 2.0 0.2079 1.9 0.93 1217.8 20.8 1230.1 14.3 1251.8 14.0 1251.8 14.0 PC 46 2.6866 3.1 0.2304 3.0 0.97 1336.6 36.8 1324.8 23.3 1305.8 15.1 1305.8 15.1 PC 34 2.6089 3.8 0.2218 3.7 0.97 1291.5 43.8 1303.2 28.3 1322.4 17.7 1322.4 17.7 PC 15 2.4886 4.9 0.2108 4.8 0.98 1232.8 54.1 1268.7 35.6 1330.0 18.2 1330.0 18.2 PC 101 2.5731 3.4 0.2178 3.3 0.96 1270.0 37.6 1293.0 24.8 1331.4 17.7 1331.4 17.7 PC 21 2.8697 2.2 0.2384 2.1 0.94 1378.4 26.3 1374.0 16.9 1367.2 14.3 1367.2 14.3 PC 27 2.8866 2.8 0.2377 2.7 0.97 1374.8 34.0 1378.4 21.3 1383.9 12.9 1383.9 12.9 PC 13 2.9313 3.0 0.2394 2.9 0.95 1383.8 36.1 1390.0 23.0 1399.6 17.7 1399.6 17.7 PC 4 2.9014 2.3 0.2369 2.2 0.96 1370.5 27.8 1382.3 17.7 1400.5 12.9 1400.5 12.9 PC 16 2.8679 2.7 0.2339 2.6 0.97 1354.6 32.3 1373.5 20.6 1403.0 13.0 1403.0 13.0 PC 25 2.9385 2.8 0.2395 2.6 0.93 1383.8 32.2 1391.9 21.1 1404.2 20.0 1404.2 20.0 PC 109 2.9990 2.6 0.2438 2.6 0.98 1406.3 32.5 1407.4 20.0 1409.0 11.0 1409.0 11.0 PC 29 3.0416 2.7 0.2433 2.6 0.96 1403.6 33.2 1418.1 20.8 1439.9 13.6 1439.9 13.6 PC 78 3.1188 2.4 0.2492 2.4 0.97 1434.1 30.3 1437.3 18.6 1442.0 10.4 1442.0 10.4 PC 70 3.2156 3.0 0.2503 2.9 0.96 1439.9 37.7 1460.9 23.5 1491.7 15.8 1491.7 15.8 PC 8 3.7555 4.4 0.2779 4.4 0.99 1581.0 61.4 1583.3 35.6 1586.3 13.6 1586.3 13.6 PC 56 10.4828 2.9 0.4516 2.8 0.96 2402.3 55.3 2478.4 26.6 2541.3 13.4 2541.3 13.4 PC 51 12.0347 4.1 0.5028 4.0 0.98 2625.7 86.2 2607.1 38.2 2592.7 13.0 2592.7 13.0 PC 2 11.4901 2.1 0.4696 1.9 0.92 2481.8 39.3 2563.8 19.2 2629.3 13.0 2629.3 13.0 PC 50 11.5237 2.7 0.4695 2.6 0.97 2481.6 53.8 2566.5 25.1 2634.3 10.2 2634.3 10.2 PC 41 11.8287 3.6 0.4804 3.5 0.99 2529.1 73.5 2590.9 33.4 2639.7 10.0 2639.7 10.0 PC 102 12.4356 3.0 0.5028 2.9 0.97 2625.6 62.3 2637.9 27.9 2647.3 11.1 2647.3 11.1 PC 58 12.1450 2.1 0.4877 2.0 0.95 2560.6 42.5 2615.7 20.0 2658.6 11.4 2658.6 11.4 PC 52 12.9620 2.7 0.5173 2.6 0.97 2687.7 56.8 2676.9 25.2 2668.7 11.6 2668.7 11.6 PC 32 12.5738 3.1 0.5017 3.0 0.98 2621.2 65.6 2648.3 29.4 2669.0 11.4 2669.0 11.4

PC 105 13.1994 3.9 0.5231 3.8 0.99 2712.2 84.5 2694.0 36.6 2680.4 10.8 2680.4 10.8 PC 47 13.2496 2.1 0.5246 2.0 0.95 2718.6 43.9 2697.6 19.7 2681.9 11.1 2681.9 11.1 PC 67 12.9381 3.0 0.5075 2.9 0.97 2646.1 63.9 2675.2 28.5 2697.2 11.1 2697.2 11.1 PC 92 13.7736 2.6 0.5229 2.6 0.97 2711.5 56.6 2734.3 24.9 2751.1 10.5 2751.1 10.5 PC 94 15.1926 3.7 0.5546 3.6 0.97 2844.4 82.2 2827.4 34.9 2815.3 13.3 2815.3 13.3

Table 5. Blaylock

Isotope ratios Apparent ages (Ma) Best age BOK-27

Analysis ± ± error ± ± ± ± 207Pb/235U* 206Pb/238U 206Pb/238U 207Pb/235U 206Pb/207Pb (%) (%) corr. (Ma) (Ma) (Ma) (Ma) (Ma)

BOK 113 0.5702 2.7 0.0737 2.6 0.95 458.3 11.3 458.1 9.9 457.0 18.3 458.3 11.3 BOK 137 1.0317 1.9 0.1181 1.7 0.93 719.8 11.9 719.8 9.6 719.6 14.1 719.8 11.9 BOK 84 1.6004 4.5 0.1649 4.3 0.97 983.9 39.6 970.4 28.0 939.8 22.3 939.8 22.3 BOK 1 1.6017 2.7 0.1622 2.6 0.96 968.9 23.0 970.9 16.6 975.4 14.9 975.4 14.9 BOK 95 1.7100 2.5 0.1718 2.3 0.95 1021.8 22.2 1012.3 15.9 991.8 16.0 991.8 16.0 BOK 172 1.6950 2.6 0.1702 2.4 0.94 1013.2 22.9 1006.7 16.6 992.3 18.3 992.3 18.3 BOK 67 1.6085 2.5 0.1615 2.4 0.95 965.1 21.7 973.5 15.9 992.6 15.8 992.6 15.8 BOK 119 1.6938 2.8 0.1697 2.7 0.96 1010.4 25.5 1006.2 18.2 997.0 16.2 997.0 16.2 BOK 109 1.6941 3.0 0.1696 2.8 0.94 1009.7 25.9 1006.3 18.9 999.0 21.3 999.0 21.3 BOK 274 1.6443 2.9 0.1644 2.7 0.95 981.4 24.9 987.4 18.2 1000.7 18.4 1000.7 18.4 BOK 87 1.7559 2.1 0.1754 1.9 0.91 1041.8 18.3 1029.3 13.6 1002.9 18.1 1002.9 18.1 BOK 181 1.7237 2.8 0.1720 2.6 0.95 1023.1 24.9 1017.4 17.7 1005.0 16.7 1005.0 16.7

BOK 246 1.7212 2.6 0.1716 2.4 0.95 1020.7 23.0 1016.5 16.5 1007.3 15.9 1007.3 15.9 BOK 292 1.7757 2.8 0.1769 2.6 0.96 1049.9 25.6 1036.6 18.0 1008.8 16.6 1008.8 16.6 BOK 9 1.6029 3.4 0.1596 3.2 0.93 954.6 28.2 971.3 21.3 1009.3 24.8 1009.3 24.8 BOK 94 1.7730 2.6 0.1765 2.5 0.95 1047.6 24.0 1035.6 17.0 1010.4 16.8 1010.4 16.8 BOK 298 1.7468 3.1 0.1737 2.9 0.95 1032.3 27.7 1026.0 19.7 1012.5 19.1 1012.5 19.1 BOK 55 1.6826 2.7 0.1673 2.6 0.95 996.9 23.9 1002.0 17.3 1013.0 17.0 1013.0 17.0 BOK 234 1.6386 3.2 0.1628 3.0 0.96 972.1 27.5 985.2 19.9 1014.3 16.8 1014.3 16.8 BOK 43 1.6732 3.1 0.1661 2.9 0.95 990.8 26.9 998.4 19.6 1015.0 19.9 1015.0 19.9 BOK 100 1.8074 2.8 0.1795 2.7 0.97 1064.1 26.4 1048.1 18.2 1015.1 14.1 1015.1 14.1 BOK 226 1.7719 1.8 0.1759 1.7 0.93 1044.5 16.2 1035.2 11.7 1015.6 13.1 1015.6 13.1 BOK 8 1.7506 2.2 0.1737 2.1 0.95 1032.6 20.3 1027.4 14.4 1016.3 13.6 1016.3 13.6 BOK 155 1.7759 2.7 0.1759 2.5 0.94 1044.5 24.5 1036.7 17.6 1020.1 19.3 1020.1 19.3 BOK 52 1.7424 2.5 0.1726 2.4 0.96 1026.2 22.7 1024.3 16.1 1020.3 14.2 1020.3 14.2 BOK 92 1.7502 3.6 0.1732 3.4 0.94 1029.6 32.5 1027.2 23.4 1022.1 24.5 1022.1 24.5 BOK 263 1.7331 3.2 0.1714 3.1 0.96 1020.1 28.8 1020.9 20.5 1022.7 18.1 1022.7 18.1 BOK 258 1.7689 3.1 0.1750 3.0 0.97 1039.4 28.8 1034.1 20.1 1023.0 15.7 1023.0 15.7 BOK 21 1.6348 2.8 0.1617 2.6 0.94 966.2 23.2 983.7 17.3 1023.1 18.8 1023.1 18.8 BOK 103 1.7162 3.3 0.1697 3.1 0.95 1010.6 29.3 1014.6 21.1 1023.2 20.5 1023.2 20.5 BOK 230 1.7784 2.7 0.1758 2.5 0.94 1044.0 24.5 1037.6 17.6 1024.1 19.3 1024.1 19.3 BOK 99 1.7895 2.3 0.1768 2.2 0.96 1049.5 21.1 1041.6 14.8 1025.0 13.5 1025.0 13.5 BOK 192 1.6738 3.2 0.1654 3.1 0.96 986.6 28.0 998.6 20.3 1025.2 18.3 1025.2 18.3 BOK 28 1.6854 2.7 0.1665 2.6 0.97 992.7 24.3 1003.0 17.4 1025.6 13.9 1025.6 13.9 BOK 185 1.7807 3.5 0.1758 3.4 0.96 1044.0 33.0 1038.4 23.1 1026.7 19.2 1026.7 19.2 BOK 202 1.7436 2.6 0.1720 2.5 0.94 1023.4 23.4 1024.8 17.0 1027.9 18.0 1027.9 18.0 BOK 304 1.7097 3.0 0.1686 2.9 0.97 1004.3 26.9 1012.2 19.1 1029.2 15.2 1029.2 15.2 BOK 73 1.7867 2.6 0.1761 2.4 0.94 1045.7 23.3 1040.6 16.8 1030.1 18.3 1030.1 18.3 BOK 134 1.7872 2.5 0.1761 2.3 0.95 1045.8 22.7 1040.8 16.0 1030.4 15.0 1030.4 15.0 BOK 310 1.7702 2.6 0.1744 2.6 0.97 1036.4 24.5 1034.6 17.1 1030.6 13.1 1030.6 13.1 BOK 179 1.8079 3.9 0.1781 3.8 0.97 1056.7 36.9 1048.3 25.5 1031.0 18.7 1031.0 18.7

BOK 300 1.7566 2.9 0.1730 2.8 0.96 1028.8 26.8 1029.6 18.9 1031.3 16.0 1031.3 16.0 BOK 215 1.7169 3.8 0.1691 3.7 0.97 1007.2 34.1 1014.9 24.1 1031.5 18.0 1031.5 18.0 BOK 279 1.7746 2.3 0.1748 2.1 0.94 1038.4 20.6 1036.2 14.8 1031.6 15.7 1031.6 15.7 BOK 163 1.8218 3.5 0.1794 3.4 0.97 1063.5 33.6 1053.3 23.1 1032.3 17.2 1032.3 17.2 BOK 262 1.7699 2.9 0.1742 2.8 0.96 1035.2 26.5 1034.5 18.8 1033.0 17.4 1033.0 17.4 BOK 77 1.7352 2.4 0.1707 2.2 0.92 1015.8 20.8 1021.7 15.6 1034.3 19.5 1034.3 19.5 BOK 165 1.7680 3.8 0.1739 3.6 0.95 1033.5 34.8 1033.8 24.9 1034.3 24.6 1034.3 24.6 BOK 148 1.8283 2.6 0.1798 2.5 0.95 1065.9 24.3 1055.7 17.1 1034.6 16.8 1034.6 16.8 BOK 158 1.8057 2.7 0.1773 2.6 0.94 1052.3 24.9 1047.5 17.9 1037.4 19.1 1037.4 19.1 BOK 123 1.7673 3.3 0.1735 3.3 0.98 1031.3 31.1 1033.5 21.6 1038.2 13.8 1038.2 13.8 BOK 198 1.8630 3.6 0.1829 3.5 0.97 1082.6 34.7 1068.1 23.7 1038.4 17.3 1038.4 17.3 BOK 241 1.8363 3.9 0.1802 3.8 0.96 1067.9 37.1 1058.5 25.9 1039.3 23.4 1039.3 23.4 BOK 259 1.8537 3.0 0.1819 2.9 0.95 1077.1 28.3 1064.8 19.8 1039.6 18.5 1039.6 18.5 BOK 41 1.8067 2.7 0.1772 2.5 0.93 1051.8 23.9 1047.9 17.4 1039.6 20.4 1039.6 20.4 BOK 68 1.6695 2.9 0.1637 2.6 0.90 977.3 23.4 997.0 18.3 1040.6 25.7 1040.6 25.7 BOK 233 1.8164 3.3 0.1780 3.2 0.95 1056.1 30.8 1051.4 21.9 1041.6 21.4 1041.6 21.4 BOK 76 1.5236 2.8 0.1493 2.6 0.93 896.9 21.7 939.9 17.1 1042.1 20.9 1042.1 20.9 BOK 305 1.7387 2.5 0.1703 2.4 0.96 1013.8 22.7 1023.0 16.3 1042.6 14.7 1042.6 14.7 BOK 237 1.7379 3.1 0.1702 2.9 0.96 1013.2 27.5 1022.7 19.7 1043.1 17.8 1043.1 17.8 BOK 79 1.7316 4.2 0.1695 4.1 0.97 1009.6 37.9 1020.3 27.0 1043.4 22.2 1043.4 22.2 BOK 205 1.7882 3.2 0.1751 3.0 0.96 1039.9 29.0 1041.2 20.6 1043.8 18.7 1043.8 18.7 BOK 169 1.8030 2.9 0.1765 2.8 0.96 1047.8 26.6 1046.5 18.8 1043.8 16.7 1043.8 16.7 BOK 54 1.7821 2.2 0.1745 2.1 0.95 1036.6 20.2 1039.0 14.5 1043.9 14.4 1043.9 14.4 BOK 112 1.7566 3.4 0.1719 3.3 0.96 1022.3 30.9 1029.6 22.0 1045.1 19.5 1045.1 19.5 BOK 127 1.8328 4.5 0.1792 4.4 0.97 1062.4 43.0 1057.3 29.7 1046.6 21.0 1046.6 21.0 BOK 102 1.7298 5.4 0.1691 5.2 0.97 1007.1 48.6 1019.7 34.5 1046.7 24.8 1046.7 24.8 BOK 221 1.7801 2.8 0.1740 2.6 0.95 1033.9 25.1 1038.2 17.9 1047.3 16.9 1047.3 16.9 BOK 270 1.7494 2.3 0.1709 2.2 0.94 1017.1 20.8 1026.9 15.2 1047.9 15.8 1047.9 15.8 BOK 159 1.8275 2.7 0.1785 2.5 0.94 1058.6 24.4 1055.4 17.4 1048.7 17.9 1048.7 17.9

BOK 286 1.8469 6.2 0.1803 5.9 0.96 1068.8 58.4 1062.3 40.6 1049.1 33.3 1049.1 33.3 BOK 60 1.7879 3.3 0.1745 3.2 0.98 1036.6 31.0 1041.1 21.5 1050.5 13.0 1050.5 13.0 BOK 23 1.7791 4.3 0.1735 4.0 0.94 1031.6 38.1 1037.8 27.7 1051.0 29.1 1051.0 29.1 BOK 25 1.8005 3.0 0.1755 2.9 0.96 1042.5 27.8 1045.6 19.7 1052.2 17.4 1052.2 17.4 BOK 255 1.9162 3.5 0.1868 3.4 0.95 1104.0 34.1 1086.7 23.5 1052.3 21.3 1052.3 21.3 BOK 88 1.6687 2.2 0.1627 2.1 0.94 971.6 19.1 996.7 14.2 1052.4 15.1 1052.4 15.1 BOK 252 1.8405 2.9 0.1793 2.8 0.96 1063.4 27.3 1060.0 19.1 1053.3 16.1 1053.3 16.1 BOK 208 1.6437 2.2 0.1601 2.1 0.95 957.5 18.6 987.1 13.9 1053.7 13.8 1053.7 13.8 BOK 142 1.7918 3.4 0.1745 3.2 0.95 1036.6 31.1 1042.5 22.2 1054.8 21.1 1054.8 21.1 BOK 15 1.7761 2.4 0.1728 2.2 0.93 1027.6 21.4 1036.8 15.7 1056.1 17.6 1056.1 17.6 BOK 97 1.5134 2.5 0.1472 2.4 0.96 885.5 20.1 935.8 15.6 1056.3 15.2 1056.3 15.2 BOK 20 1.7875 2.6 0.1738 2.4 0.93 1033.2 23.4 1040.9 17.2 1057.1 19.6 1057.1 19.6 BOK 115 1.9194 3.0 0.1866 2.8 0.96 1103.2 28.9 1087.9 19.8 1057.3 16.8 1057.3 16.8 BOK 122 1.8616 3.2 0.1808 3.0 0.96 1071.2 30.0 1067.5 21.0 1060.1 18.7 1060.1 18.7 BOK 250 1.8366 2.6 0.1783 2.5 0.97 1057.9 24.9 1058.6 17.3 1060.2 13.4 1060.2 13.4 BOK 315 1.8459 2.4 0.1792 2.3 0.94 1062.6 22.4 1062.0 16.0 1060.6 16.8 1060.6 16.8 BOK 75 1.7282 3.5 0.1677 3.3 0.95 999.3 30.9 1019.1 22.5 1061.8 21.7 1061.8 21.7 BOK 166 1.9259 6.0 0.1869 5.9 0.98 1104.3 59.9 1090.1 40.1 1061.9 21.1 1061.9 21.1 BOK 276 1.8397 2.6 0.1784 2.5 0.95 1058.0 24.4 1059.7 17.2 1063.3 16.0 1063.3 16.0 BOK 313 1.8580 3.0 0.1801 2.9 0.96 1067.7 28.6 1066.3 20.0 1063.5 17.2 1063.5 17.2 BOK 242 1.8026 3.1 0.1748 3.0 0.97 1038.2 28.8 1046.4 20.3 1063.5 15.6 1063.5 15.6 BOK 216 1.8077 3.1 0.1752 3.0 0.97 1040.4 28.5 1048.2 20.0 1064.6 15.4 1064.6 15.4 BOK 136 1.8384 3.3 0.1781 3.1 0.95 1056.6 30.3 1059.3 21.5 1064.8 20.0 1064.8 20.0 BOK 66 1.7849 4.1 0.1728 3.9 0.96 1027.4 37.5 1040.0 26.8 1066.4 23.5 1066.4 23.5 BOK 117 1.8230 2.9 0.1764 2.8 0.96 1047.1 26.9 1053.8 19.1 1067.5 16.8 1067.5 16.8 BOK 46 1.8649 2.7 0.1803 2.6 0.94 1068.9 25.1 1068.7 17.8 1068.5 17.8 1068.5 17.8 BOK 133 1.9324 2.6 0.1869 2.4 0.93 1104.3 24.7 1092.4 17.4 1068.7 18.6 1068.7 18.6 BOK 294 1.9151 4.1 0.1852 4.0 0.98 1095.2 40.1 1086.4 27.1 1068.7 16.3 1068.7 16.3 BOK 44 1.8435 2.4 0.1782 2.2 0.93 1057.4 21.9 1061.1 15.9 1068.8 18.1 1068.8 18.1

BOK 31 1.8353 3.6 0.1774 3.4 0.94 1052.8 33.4 1058.2 24.0 1069.3 24.5 1069.3 24.5 BOK 249 1.8385 3.5 0.1777 3.2 0.94 1054.3 31.6 1059.3 22.7 1069.7 23.8 1069.7 23.8 BOK 121 1.8124 2.9 0.1751 2.7 0.95 1040.2 26.4 1049.9 19.0 1070.2 18.3 1070.2 18.3 BOK 193 1.8828 4.1 0.1819 3.9 0.95 1077.3 38.6 1075.1 27.1 1070.6 25.0 1070.6 25.0 BOK 194 1.9189 2.1 0.1854 1.9 0.93 1096.2 19.6 1087.7 13.9 1070.8 15.2 1070.8 15.2 BOK 281 1.9173 2.7 0.1852 2.6 0.95 1095.2 25.8 1087.1 18.0 1071.1 16.4 1071.1 16.4 BOK 183 1.8123 2.7 0.1750 2.6 0.95 1039.6 24.9 1049.9 17.9 1071.5 17.5 1071.5 17.5 BOK 4 1.8714 2.2 0.1806 2.1 0.94 1070.5 20.3 1071.0 14.5 1072.1 15.5 1072.1 15.5 BOK 301 1.8809 2.9 0.1814 2.8 0.97 1074.4 27.9 1074.4 19.2 1074.4 13.5 1074.4 13.5 BOK 89 1.8039 4.7 0.1739 4.6 0.98 1033.6 43.7 1046.9 30.6 1074.7 20.5 1074.7 20.5 BOK 293 1.8601 4.0 0.1792 3.9 0.97 1062.9 38.2 1067.0 26.6 1075.6 20.5 1075.6 20.5 BOK 229 1.7062 3.5 0.1644 3.4 0.98 981.0 31.2 1010.8 22.5 1076.1 15.3 1076.1 15.3 BOK 170 1.8581 5.6 0.1789 5.4 0.97 1061.1 53.0 1066.3 37.0 1077.1 28.6 1077.1 28.6 BOK 40 1.8378 3.2 0.1769 3.1 0.96 1050.1 30.2 1059.1 21.3 1077.7 17.9 1077.7 17.9 BOK 296 1.9389 3.9 0.1866 3.8 0.97 1103.0 38.5 1094.6 26.3 1078.0 19.7 1078.0 19.7 BOK 253 1.8531 3.4 0.1783 3.2 0.94 1057.9 31.1 1064.5 22.4 1078.1 23.6 1078.1 23.6 BOK 17 1.8743 2.5 0.1804 2.4 0.95 1069.0 23.7 1072.1 16.8 1078.3 15.9 1078.3 15.9 BOK 116 1.9217 2.3 0.1849 2.1 0.93 1093.7 21.6 1088.7 15.4 1078.6 16.7 1078.6 16.7 BOK 63 1.8857 3.8 0.1814 3.7 0.98 1074.6 36.5 1076.1 25.0 1079.1 15.6 1079.1 15.6 BOK 11 1.8525 2.9 0.1782 2.7 0.95 1057.0 26.6 1064.3 19.0 1079.4 18.1 1079.4 18.1 BOK 225 1.9777 2.1 0.1900 1.9 0.92 1121.2 19.8 1107.9 14.2 1082.0 16.9 1082.0 16.9 BOK 27 1.8953 2.5 0.1820 2.4 0.95 1078.1 23.9 1079.5 16.8 1082.1 15.1 1082.1 15.1 BOK 129 1.9006 3.1 0.1825 2.9 0.93 1080.6 28.8 1081.3 20.8 1082.8 23.6 1082.8 23.6 BOK 153 1.8476 2.8 0.1773 2.7 0.94 1052.1 25.9 1062.6 18.6 1084.2 18.6 1084.2 18.6 BOK 154 1.9043 3.7 0.1827 3.5 0.96 1081.5 35.2 1082.6 24.6 1084.8 21.7 1084.8 21.7 BOK 188 1.9469 3.2 0.1867 3.1 0.96 1103.3 31.1 1097.4 21.5 1085.6 18.8 1085.6 18.8 BOK 244 1.9057 2.3 0.1826 2.2 0.95 1081.1 22.1 1083.1 15.6 1087.2 15.3 1087.2 15.3 BOK 167 1.9295 2.9 0.1848 2.8 0.95 1093.3 28.2 1091.4 19.6 1087.6 17.6 1087.6 17.6 BOK 203 1.9422 3.2 0.1859 3.0 0.95 1099.0 30.5 1095.8 21.2 1089.3 19.6 1089.3 19.6

BOK 254 1.8410 3.4 0.1761 3.1 0.93 1045.8 30.2 1060.2 22.1 1090.0 24.2 1090.0 24.2 BOK 65 1.8951 2.9 0.1812 2.8 0.96 1073.5 27.6 1079.4 19.3 1091.2 16.2 1091.2 16.2 BOK 71 1.7941 2.8 0.1713 2.8 0.97 1019.3 26.0 1043.3 18.5 1094.0 13.3 1094.0 13.3 BOK 101 1.9579 3.3 0.1868 3.2 0.97 1104.0 32.0 1101.2 21.9 1095.5 16.5 1095.5 16.5 BOK 207 1.8976 2.6 0.1810 2.5 0.95 1072.3 24.5 1080.2 17.3 1096.2 16.0 1096.2 16.0 BOK 56 1.8245 2.8 0.1740 2.7 0.95 1034.0 25.7 1054.3 18.6 1096.7 17.7 1096.7 17.7 BOK 224 1.8873 2.7 0.1799 2.5 0.94 1066.4 25.0 1076.6 18.0 1097.5 18.8 1097.5 18.8 BOK 218 1.8439 3.4 0.1756 3.2 0.93 1042.9 30.8 1061.3 22.5 1099.3 24.5 1099.3 24.5 BOK 69 1.9529 3.5 0.1860 3.4 0.97 1099.5 34.7 1099.5 23.7 1099.3 16.1 1099.3 16.1 BOK 175 1.9194 3.2 0.1825 3.1 0.96 1080.7 30.4 1087.9 21.2 1102.2 17.2 1102.2 17.2 BOK 245 1.8631 2.9 0.1766 2.8 0.96 1048.3 27.2 1068.1 19.4 1108.8 17.1 1108.8 17.1 BOK 47 1.8823 2.7 0.1784 2.5 0.94 1058.1 24.6 1074.9 17.7 1109.1 17.5 1109.1 17.5 BOK 306 1.9876 3.0 0.1881 3.0 0.98 1111.1 30.4 1111.3 20.6 1111.6 12.3 1111.6 12.3 BOK 191 1.9305 2.7 0.1826 2.6 0.95 1081.1 25.6 1091.7 18.2 1113.0 17.6 1113.0 17.6 BOK 62 2.0286 3.6 0.1918 3.5 0.97 1131.3 36.0 1125.2 24.3 1113.3 17.2 1113.3 17.2 BOK 178 1.9199 3.4 0.1814 3.2 0.95 1074.6 31.7 1088.0 22.6 1115.0 21.9 1115.0 21.9 BOK 80 1.9559 3.3 0.1845 3.1 0.95 1091.3 31.2 1100.5 21.9 1118.7 19.7 1118.7 19.7 BOK 50 2.0108 3.1 0.1896 2.9 0.96 1119.2 30.2 1119.2 20.7 1119.0 16.4 1119.0 16.4 BOK 156 1.8992 2.8 0.1791 2.7 0.96 1061.9 26.4 1080.8 18.7 1119.1 15.9 1119.1 15.9 BOK 256 2.0493 3.5 0.1930 3.4 0.97 1137.7 35.2 1132.0 23.8 1121.3 17.6 1121.3 17.6 BOK 299 2.0760 2.9 0.1955 2.7 0.95 1151.2 28.8 1140.9 19.8 1121.4 18.6 1121.4 18.6 BOK 297 1.8467 3.7 0.1737 2.6 0.69 1032.5 24.5 1062.2 24.6 1123.8 53.8 1123.8 53.8 BOK 86 1.8122 2.7 0.1702 2.6 0.96 1013.5 24.0 1049.9 17.5 1126.4 15.8 1126.4 15.8 BOK 236 2.0254 3.5 0.1900 3.4 0.96 1121.3 35.1 1124.1 24.1 1129.5 19.5 1129.5 19.5 BOK 271 2.0482 2.7 0.1921 2.6 0.94 1132.8 26.8 1131.7 18.8 1129.6 19.1 1129.6 19.1 BOK 247 2.0850 2.9 0.1955 2.7 0.94 1150.9 28.6 1143.9 19.9 1130.6 20.4 1130.6 20.4 BOK 174 2.0815 2.6 0.1948 2.5 0.96 1147.1 25.8 1142.7 17.5 1134.4 14.0 1134.4 14.0 BOK 64 1.9656 4.3 0.1836 4.2 0.98 1086.8 42.3 1103.8 29.1 1137.4 17.9 1137.4 17.9 BOK 168 2.0050 2.7 0.1871 2.5 0.94 1105.7 25.3 1117.2 18.0 1139.6 18.7 1139.6 18.7

BOK 78 1.9936 3.4 0.1860 3.3 0.97 1099.9 33.5 1113.3 23.1 1139.7 16.4 1139.7 16.4 BOK 312 2.0309 2.9 0.1895 2.8 0.96 1118.5 28.6 1125.9 19.8 1140.3 16.5 1140.3 16.5 BOK 275 2.1296 2.9 0.1987 2.8 0.96 1168.1 29.6 1158.5 19.9 1140.5 15.5 1140.5 15.5 BOK 110 2.0552 4.1 0.1916 3.9 0.95 1129.8 40.4 1134.0 27.9 1142.1 24.3 1142.1 24.3 BOK 91 2.0672 4.5 0.1924 4.4 0.97 1134.3 45.6 1138.0 31.0 1145.1 21.9 1145.1 21.9 BOK 13 1.8772 3.3 0.1747 3.2 0.96 1037.8 30.2 1073.1 21.8 1145.4 19.2 1145.4 19.2 BOK 45 2.0569 2.6 0.1912 2.4 0.94 1127.8 25.3 1134.6 17.8 1147.6 17.6 1147.6 17.6 BOK 217 2.0596 2.5 0.1913 2.4 0.96 1128.4 24.6 1135.5 16.9 1149.1 14.0 1149.1 14.0 BOK 182 2.1120 2.3 0.1961 2.2 0.96 1154.5 23.6 1152.7 16.1 1149.5 13.6 1149.5 13.6 BOK 5 2.0509 3.0 0.1904 2.9 0.96 1123.6 29.7 1132.6 20.5 1149.8 16.5 1149.8 16.5 BOK 135 2.0941 2.4 0.1944 2.2 0.90 1145.2 22.6 1146.9 16.5 1150.0 21.1 1150.0 21.1 BOK 220 2.1255 3.3 0.1971 3.2 0.96 1159.6 33.8 1157.1 22.9 1152.5 18.6 1152.5 18.6 BOK 308 2.0147 2.5 0.1865 2.4 0.95 1102.5 23.9 1120.5 16.8 1155.5 15.1 1155.5 15.1 BOK 70 2.0559 3.6 0.1903 3.6 0.98 1123.1 36.6 1134.3 24.8 1155.6 14.9 1155.6 14.9 BOK 201 2.1008 3.3 0.1944 3.2 0.96 1145.4 33.7 1149.1 22.9 1156.1 17.5 1156.1 17.5 BOK 144 2.1081 2.5 0.1951 2.4 0.95 1148.7 25.1 1151.4 17.3 1156.5 15.8 1156.5 15.8 BOK 161 2.1505 3.1 0.1988 2.9 0.96 1168.9 31.5 1165.2 21.2 1158.4 16.6 1158.4 16.6 BOK 141 2.0758 2.5 0.1918 2.4 0.96 1131.2 25.3 1140.9 17.5 1159.3 14.9 1159.3 14.9 BOK 210 1.8605 4.2 0.1719 4.1 0.97 1022.6 38.7 1067.2 27.9 1159.4 20.9 1159.4 20.9 BOK 284 2.0688 3.3 0.1911 3.2 0.96 1127.5 33.4 1138.5 22.9 1159.6 17.6 1159.6 17.6 BOK 291 2.1290 3.1 0.1966 3.0 0.97 1157.0 32.1 1158.3 21.7 1160.6 15.9 1160.6 15.9 BOK 222 2.0851 5.2 0.1924 4.9 0.95 1134.6 51.0 1143.9 35.4 1161.7 31.8 1161.7 31.8 BOK 278 2.1911 3.6 0.2020 3.5 0.97 1185.9 37.6 1178.2 25.0 1164.1 17.5 1164.1 17.5 BOK 3 2.1147 2.9 0.1949 2.7 0.93 1148.0 28.1 1153.6 19.7 1164.1 20.2 1164.1 20.2 BOK 289 2.1571 2.9 0.1987 2.8 0.97 1168.2 29.8 1167.3 20.0 1165.6 14.4 1165.6 14.4 BOK 227 2.1409 3.1 0.1971 2.9 0.95 1160.0 30.9 1162.1 21.3 1166.1 19.8 1166.1 19.8 BOK 85 2.0967 2.4 0.1930 2.2 0.93 1137.7 23.1 1147.7 16.3 1166.7 17.3 1166.7 17.3 BOK 214 2.0863 3.7 0.1920 3.6 0.97 1132.4 37.6 1144.3 25.5 1166.8 16.6 1166.8 16.6 BOK 83 2.1811 1.9 0.2007 1.8 0.95 1178.9 19.6 1175.0 13.4 1168.0 12.4 1168.0 12.4

BOK 277 2.1706 3.3 0.1996 3.2 0.96 1173.2 34.1 1171.7 23.1 1168.8 19.3 1168.8 19.3 BOK 240 2.1614 2.6 0.1987 2.5 0.97 1168.1 27.2 1168.7 18.1 1169.9 11.6 1169.9 11.6 BOK 96 2.0369 3.4 0.1871 2.9 0.85 1105.5 29.5 1127.9 23.3 1171.5 35.6 1171.5 35.6 BOK 146 2.0901 4.7 0.1917 4.5 0.96 1130.7 47.1 1145.5 32.3 1173.7 24.6 1173.7 24.6 BOK 105 2.1583 3.1 0.1979 2.9 0.96 1163.9 31.4 1167.7 21.4 1174.8 17.7 1174.8 17.7 BOK 211 2.1563 2.1 0.1976 1.9 0.93 1162.6 20.6 1167.1 14.4 1175.4 14.8 1175.4 14.8 BOK 106 2.2063 3.4 0.2017 3.3 0.97 1184.5 36.0 1183.0 24.0 1180.3 16.5 1180.3 16.5 BOK 30 2.1331 2.2 0.1950 2.1 0.95 1148.5 22.5 1159.6 15.5 1180.4 13.4 1180.4 13.4 BOK 90 2.1791 2.2 0.1988 2.0 0.91 1168.6 21.8 1174.4 15.6 1185.1 18.6 1185.1 18.6 BOK 162 2.2078 2.7 0.2011 2.6 0.95 1181.5 27.9 1183.5 18.9 1187.2 15.8 1187.2 15.8 BOK 124 2.2594 2.8 0.2054 2.6 0.94 1204.4 28.7 1199.7 19.6 1191.4 18.6 1191.4 18.6 BOK 238 2.1379 4.0 0.1942 3.8 0.97 1144.2 40.2 1161.1 27.5 1192.8 20.4 1192.8 20.4 BOK 196 2.2077 2.4 0.2005 2.3 0.95 1177.9 25.0 1183.5 17.1 1193.7 15.1 1193.7 15.1 BOK 151 2.3151 2.3 0.2101 2.1 0.92 1229.4 23.3 1216.9 16.0 1194.9 17.4 1194.9 17.4 BOK 239 2.2069 3.7 0.2000 3.5 0.97 1175.3 38.1 1183.2 25.7 1197.8 18.6 1197.8 18.6 BOK 295 2.2475 5.4 0.2032 5.3 0.98 1192.3 58.1 1196.0 38.2 1202.6 18.9 1202.6 18.9 BOK 2 2.1044 4.1 0.1902 3.8 0.93 1122.6 38.8 1150.2 27.9 1202.8 29.7 1202.8 29.7 BOK 280 2.1545 4.3 0.1946 4.1 0.96 1146.4 43.5 1166.5 30.0 1203.9 24.2 1203.9 24.2 BOK 290 2.2441 3.2 0.2021 3.0 0.94 1186.3 32.6 1194.9 22.5 1210.5 21.8 1210.5 21.8 BOK 243 2.0624 3.8 0.1855 3.5 0.91 1096.8 35.0 1136.4 26.1 1212.9 31.5 1212.9 31.5 BOK 164 2.3266 3.2 0.2089 3.1 0.97 1223.1 34.0 1220.4 22.4 1215.8 15.4 1215.8 15.4 BOK 219 2.3038 3.2 0.2058 3.0 0.94 1206.2 33.3 1213.5 22.7 1226.5 20.9 1226.5 20.9 BOK 213 2.2690 3.9 0.2025 3.8 0.97 1188.7 41.0 1202.7 27.5 1227.9 18.5 1227.9 18.5 BOK 39 2.0678 4.6 0.1844 4.5 0.97 1091.2 44.8 1138.2 31.6 1229.0 23.6 1229.0 23.6 BOK 260 2.4162 2.6 0.2155 2.5 0.94 1257.9 28.2 1247.4 18.9 1229.4 17.8 1229.4 17.8 BOK 14 2.2507 2.3 0.2004 2.1 0.95 1177.7 23.0 1197.0 15.9 1232.1 14.3 1232.1 14.3 BOK 126 2.4131 2.4 0.2149 2.4 0.97 1254.8 26.8 1246.5 17.5 1232.3 12.4 1232.3 12.4 BOK 282 2.4250 2.6 0.2146 2.5 0.96 1253.1 28.7 1250.0 18.9 1244.7 14.9 1244.7 14.9 BOK 48 2.4413 3.0 0.2158 2.9 0.96 1259.9 33.3 1254.9 21.9 1246.3 17.2 1246.3 17.2

BOK 264 2.4486 3.1 0.2165 3.0 0.94 1263.3 33.9 1257.0 22.6 1246.3 20.1 1246.3 20.1 BOK 209 2.2410 2.7 0.1980 2.5 0.92 1164.6 26.8 1194.0 19.1 1247.6 20.3 1247.6 20.3 BOK 104 2.4730 3.5 0.2184 3.3 0.97 1273.5 38.5 1264.2 25.0 1248.3 17.7 1248.3 17.7 BOK 272 2.3963 4.2 0.2111 4.0 0.96 1234.8 45.0 1241.5 29.8 1253.1 22.2 1253.1 22.2 BOK 265 2.3908 2.7 0.2104 2.6 0.98 1230.8 29.6 1239.9 19.3 1255.6 10.8 1255.6 10.8 BOK 98 2.4966 2.5 0.2191 2.4 0.96 1277.2 28.2 1271.1 18.3 1260.8 13.1 1260.8 13.1 BOK 51 2.4767 3.6 0.2171 3.4 0.95 1266.4 39.0 1265.2 25.8 1263.2 21.6 1263.2 21.6 BOK 190 2.3949 4.5 0.2095 4.4 0.97 1226.4 48.9 1241.1 32.2 1266.7 20.4 1266.7 20.4 BOK 19 2.4225 3.0 0.2114 2.9 0.95 1236.5 32.2 1249.3 21.5 1271.5 17.3 1271.5 17.3 BOK 111 2.4395 2.7 0.2125 2.5 0.96 1242.0 28.8 1254.3 19.1 1275.5 14.7 1275.5 14.7 BOK 149 2.5094 2.6 0.2185 2.5 0.95 1274.0 28.3 1274.8 18.7 1276.0 15.0 1276.0 15.0 BOK 33 2.4462 2.2 0.2129 2.1 0.93 1244.5 23.5 1256.3 16.0 1276.6 15.6 1276.6 15.6 BOK 26 2.5687 3.0 0.2221 2.9 0.97 1293.0 33.8 1291.8 21.8 1289.6 15.0 1289.6 15.0 BOK 138 2.5391 2.9 0.2188 2.7 0.95 1275.6 31.5 1283.3 20.9 1296.2 17.4 1296.2 17.4 BOK 93 2.6404 3.9 0.2271 3.8 0.98 1319.1 45.4 1312.0 28.6 1300.2 15.5 1300.2 15.5 BOK 204 2.5031 4.2 0.2144 4.1 0.98 1252.0 46.8 1272.9 30.6 1308.5 17.5 1308.5 17.5 BOK 34 2.5401 3.8 0.2165 3.7 0.97 1263.3 42.8 1283.6 27.9 1317.8 17.5 1317.8 17.5 BOK 72 2.5233 8.2 0.2150 8.1 0.99 1255.3 92.5 1278.8 59.6 1318.4 22.4 1318.4 22.4 BOK 130 2.6968 2.5 0.2297 2.3 0.94 1333.0 28.1 1327.6 18.3 1318.9 15.8 1318.9 15.8 BOK 10 2.5262 2.7 0.2150 2.5 0.94 1255.6 28.5 1279.6 19.3 1320.0 17.2 1320.0 17.2 BOK 206 2.6287 2.7 0.2237 2.6 0.95 1301.3 30.4 1308.7 20.0 1320.8 16.5 1320.8 16.5 BOK 160 2.6248 4.1 0.2233 4.0 0.96 1299.4 46.6 1307.6 30.2 1321.2 21.3 1321.2 21.3 BOK 132 2.6834 3.2 0.2282 3.1 0.96 1325.2 37.1 1323.9 23.9 1321.8 18.3 1321.8 18.3 BOK 147 2.7781 3.3 0.2360 3.2 0.96 1365.7 39.6 1349.7 24.9 1324.3 17.1 1324.3 17.1 BOK 12 2.7233 2.3 0.2313 2.2 0.96 1341.3 26.5 1334.8 16.9 1324.4 12.2 1324.4 12.2 BOK 53 2.7181 2.8 0.2309 2.7 0.96 1339.0 32.1 1333.4 20.5 1324.5 14.3 1324.5 14.3 BOK 38 2.6844 4.5 0.2278 4.3 0.97 1322.9 52.0 1324.2 33.0 1326.2 19.8 1326.2 19.8 BOK 189 2.7159 2.9 0.2304 2.8 0.97 1336.8 34.4 1332.8 21.9 1326.5 14.3 1326.5 14.3 BOK 177 2.6124 3.6 0.2202 3.5 0.97 1283.1 40.6 1304.1 26.5 1338.9 17.9 1338.9 17.9

BOK 49 2.2828 4.8 0.1924 4.0 0.83 1134.5 41.4 1207.0 33.7 1339.1 50.9 1339.1 50.9 BOK 267 2.7162 3.4 0.2282 3.3 0.95 1324.9 39.4 1332.9 25.6 1345.8 19.9 1345.8 19.9 BOK 303 2.7889 3.7 0.2330 3.5 0.96 1350.1 43.2 1352.6 27.7 1356.4 20.8 1356.4 20.8 BOK 143 2.3821 3.3 0.1983 2.7 0.82 1166.4 28.4 1237.2 23.3 1362.7 36.4 1362.7 36.4 BOK 16 2.6429 2.2 0.2197 2.1 0.94 1280.4 24.4 1312.7 16.4 1365.7 14.2 1365.7 14.2 BOK 18 2.7415 2.8 0.2276 2.7 0.95 1321.8 32.2 1339.8 21.2 1368.7 17.6 1368.7 17.6 BOK 307 2.7195 3.2 0.2247 3.0 0.93 1306.7 35.3 1333.8 23.8 1377.6 22.2 1377.6 22.2 BOK 187 2.8768 3.0 0.2376 2.8 0.95 1374.0 35.0 1375.9 22.5 1378.7 18.6 1378.7 18.6 BOK 140 2.9029 3.2 0.2396 3.1 0.98 1384.6 38.6 1382.7 24.0 1379.7 13.5 1379.7 13.5 BOK 57 2.7707 5.1 0.2284 5.0 0.99 1326.3 59.9 1347.7 37.9 1381.8 16.7 1381.8 16.7 BOK 125 2.8087 3.8 0.2313 3.8 0.98 1341.3 45.7 1357.9 28.8 1384.0 14.9 1384.0 14.9 BOK 197 2.9177 3.1 0.2401 3.0 0.96 1387.4 37.4 1386.5 23.7 1385.1 17.7 1385.1 17.7 BOK 231 2.9251 6.1 0.2406 6.0 0.99 1389.6 75.0 1388.4 45.8 1386.5 15.6 1386.5 15.6 BOK 235 2.9243 3.3 0.2402 3.1 0.94 1387.9 39.3 1388.2 25.2 1388.8 21.2 1388.8 21.2 BOK 150 2.9683 3.3 0.2431 3.2 0.96 1402.9 40.0 1399.5 25.0 1394.3 16.7 1394.3 16.7 BOK 199 2.7966 3.1 0.2287 3.0 0.96 1327.7 35.5 1354.6 23.1 1397.4 16.7 1397.4 16.7 BOK 212 2.9640 2.3 0.2423 2.2 0.95 1398.6 28.0 1398.4 17.8 1398.1 14.0 1398.1 14.0 BOK 287 2.9701 3.9 0.2425 3.7 0.97 1399.7 47.1 1400.0 29.3 1400.3 18.2 1400.3 18.2 BOK 251 2.9864 4.0 0.2436 3.8 0.95 1405.5 47.5 1404.2 30.1 1402.1 23.3 1402.1 23.3 BOK 309 3.0264 2.3 0.2468 2.2 0.95 1421.8 28.5 1414.3 17.9 1403.0 13.5 1403.0 13.5 BOK 180 2.9520 3.9 0.2404 3.8 0.97 1388.5 46.9 1395.3 29.3 1405.8 16.9 1405.8 16.9 BOK 35 2.8969 3.2 0.2351 3.1 0.96 1361.3 38.0 1381.1 24.4 1411.9 17.9 1411.9 17.9 BOK 120 2.9278 2.1 0.2376 1.9 0.91 1374.1 23.8 1389.1 15.9 1412.2 16.5 1412.2 16.5 BOK 302 3.0877 2.3 0.2496 2.1 0.91 1436.7 26.4 1429.7 17.3 1419.2 17.7 1419.2 17.7 BOK 157 3.0313 3.0 0.2447 2.9 0.97 1411.2 36.6 1415.5 22.9 1422.0 14.8 1422.0 14.8 BOK 268 3.1437 3.3 0.2530 3.1 0.96 1454.1 40.7 1443.5 25.1 1427.8 17.1 1427.8 17.1 BOK 7 3.0658 3.3 0.2454 3.2 0.97 1414.8 40.8 1424.2 25.4 1438.3 15.8 1438.3 15.8 BOK 74 3.1267 3.7 0.2500 3.6 0.98 1438.7 47.0 1439.3 28.6 1440.2 14.4 1440.2 14.4 BOK 269 3.0839 3.3 0.2465 3.1 0.96 1420.2 39.8 1428.7 25.1 1441.4 18.2 1441.4 18.2

BOK 24 2.9180 4.1 0.2317 4.0 0.97 1343.3 48.6 1386.6 31.3 1453.8 19.1 1453.8 19.1 BOK 29 3.1576 3.1 0.2501 3.0 0.96 1438.8 38.8 1446.8 24.3 1458.7 17.5 1458.7 17.5 BOK 283 3.1762 3.0 0.2514 2.9 0.96 1445.9 37.9 1451.4 23.5 1459.5 15.5 1459.5 15.5 BOK 139 3.2241 2.4 0.2549 2.3 0.96 1463.8 30.0 1463.0 18.6 1461.8 13.4 1461.8 13.4 BOK 108 3.1242 3.0 0.2461 2.8 0.94 1418.4 35.6 1438.7 23.0 1468.7 20.0 1468.7 20.0 BOK 36 3.3255 3.0 0.2619 2.9 0.96 1499.8 39.3 1487.1 23.8 1468.9 15.6 1468.9 15.6 BOK 128 3.1928 3.7 0.2509 3.6 0.97 1443.4 46.5 1455.4 28.6 1473.0 15.9 1473.0 15.9 BOK 145 3.2232 2.3 0.2532 2.1 0.92 1454.9 27.3 1462.8 17.7 1474.2 17.2 1474.2 17.2 BOK 223 3.3388 2.5 0.2621 2.4 0.97 1500.6 32.0 1490.2 19.4 1475.4 12.3 1475.4 12.3 BOK 195 3.2126 3.3 0.2520 3.2 0.97 1448.8 41.8 1460.2 25.8 1476.9 16.5 1476.9 16.5 BOK 61 3.1507 3.9 0.2471 3.8 0.97 1423.4 48.1 1445.2 29.9 1477.3 17.1 1477.3 17.1 BOK 32 3.2684 3.4 0.2562 3.4 0.98 1470.2 44.1 1473.6 26.8 1478.4 14.5 1478.4 14.5 BOK 176 3.3950 2.8 0.2660 2.6 0.94 1520.3 35.2 1503.2 21.7 1479.2 18.0 1479.2 18.0 BOK 171 3.3213 2.5 0.2601 2.4 0.96 1490.6 31.5 1486.1 19.3 1479.6 13.2 1479.6 13.2 BOK 186 3.3493 3.6 0.2604 3.5 0.97 1492.0 47.2 1492.6 28.5 1493.5 15.9 1493.5 15.9 BOK 22 3.2920 3.6 0.2558 3.5 0.97 1468.4 45.9 1479.2 28.1 1494.6 17.1 1494.6 17.1 BOK 228 3.2428 3.1 0.2506 2.6 0.83 1441.7 33.0 1467.5 23.9 1505.0 32.4 1505.0 32.4 BOK 131 3.4169 2.9 0.2636 2.8 0.95 1508.5 37.6 1508.3 23.1 1508.0 17.6 1508.0 17.6 BOK 184 4.3294 2.8 0.3086 2.7 0.96 1733.8 41.3 1699.0 23.3 1656.3 14.5 1656.3 14.5 BOK 273 4.0251 2.8 0.2865 2.7 0.96 1623.9 38.3 1639.3 22.6 1659.1 14.7 1659.1 14.7 BOK 58 4.5661 3.0 0.3153 2.9 0.96 1766.7 45.2 1743.1 25.3 1714.8 15.0 1714.8 15.0 BOK 59 4.4716 3.6 0.3055 3.5 0.96 1718.5 52.7 1725.7 30.2 1734.5 18.6 1734.5 18.6 BOK 6 4.7630 2.4 0.3216 2.3 0.96 1797.5 36.9 1778.4 20.5 1756.0 12.1 1756.0 12.1 BOK 107 11.2361 3.0 0.4815 2.9 0.97 2534.0 60.8 2542.9 28.0 2550.0 12.8 2550.0 12.8 BOK 261 12.6573 3.3 0.5160 3.2 0.97 2682.2 69.8 2654.5 30.7 2633.5 12.3 2633.5 12.3 BOK 118 10.3669 3.9 0.4225 3.8 0.98 2271.9 72.6 2468.1 35.9 2633.9 13.0 2633.9 13.0 BOK 266 9.7105 5.0 0.3925 5.0 0.99 2134.6 90.5 2407.7 46.4 2647.5 12.9 2647.5 12.9 BOK 257 12.7106 3.7 0.4995 3.6 0.97 2611.6 76.7 2658.4 34.6 2694.2 14.3 2694.2 14.3

Table 6. Hot Spring

Isotope ratios Apparent ages (Ma) Best age HS-15

Analysis ± ± error ± ± ± ± 207Pb/235U 206Pb/238U 206Pb/238U 207Pb/235U 206Pb/207Pb (%) (%) corr. (Ma) (Ma) (Ma) (Ma) (Ma)

HS 91 0.4420 2.3 0.0596 2.2 0.93 373.1 7.8 371.7 7.2 362.8 19.3 373.1 7.8 HS 85 0.5077 2.1 0.0663 2.0 0.93 413.7 7.9 416.9 7.2 434.6 17.4 413.7 7.9 HS 90 0.5068 2.3 0.0669 2.0 0.90 417.6 8.3 416.3 7.8 409.1 21.9 417.6 8.3 HS 105 0.5299 2.7 0.0676 2.3 0.85 421.7 9.4 431.7 9.5 485.8 31.5 421.7 9.4 HS 58 0.5241 2.8 0.0677 2.6 0.95 422.5 10.7 427.9 9.7 457.0 19.6 422.5 10.7 HS 43 0.5233 2.1 0.0678 1.9 0.90 422.6 7.8 427.4 7.4 452.9 20.6 422.6 7.8 HS 54 0.5181 2.2 0.0684 1.9 0.89 426.6 7.9 423.9 7.5 409.2 22.2 426.6 7.9 HS 19 0.5282 2.3 0.0695 2.2 0.93 433.4 9.1 430.6 8.2 415.9 19.3 433.4 9.1 HS 79 0.5310 1.9 0.0698 1.7 0.90 434.8 7.1 432.5 6.7 420.0 18.7 434.8 7.1 HS 42 0.5546 2.4 0.0723 2.2 0.92 449.8 9.5 448.0 8.6 439.0 20.1 449.8 9.5 HS 82 0.5878 3.6 0.0735 3.4 0.94 457.1 14.9 469.5 13.5 530.3 27.4 457.1 14.9 HS 64 0.5814 2.1 0.0745 1.9 0.91 463.4 8.5 465.4 7.8 475.2 18.8 463.4 8.5 HS 93 0.6150 1.7 0.0779 1.5 0.91 483.8 7.2 486.7 6.6 500.7 15.9 483.8 7.2 HS 95 0.7142 4.0 0.0892 2.7 0.68 551.0 14.4 547.2 17.0 531.7 64.8 551.0 14.4 HS 77 1.1441 1.9 0.1263 1.8 0.94 766.8 12.8 774.5 10.2 796.6 13.3 766.8 12.8 HS 32 1.4833 3.6 0.1555 3.5 0.96 931.5 30.3 923.6 22.1 904.7 21.9 904.7 21.9 HS 38 1.6569 3.0 0.1663 2.8 0.95 991.6 25.7 992.2 18.7 993.5 19.1 993.5 19.1

HS 10 1.5308 2.9 0.1533 2.8 0.95 919.5 24.0 942.8 18.1 997.6 18.5 997.6 18.5 HS 101 1.6799 2.4 0.1681 2.3 0.95 1001.7 21.0 1000.9 15.2 999.4 15.4 999.4 15.4 HS 110 1.7406 4.4 0.1735 4.2 0.96 1031.5 39.7 1023.7 28.1 1007.0 25.7 1007.0 25.7 HS 12 1.6694 2.1 0.1654 1.9 0.93 986.8 17.5 997.0 13.1 1019.3 15.8 1019.3 15.8 HS 48 1.7655 3.3 0.1746 3.0 0.91 1037.2 28.5 1032.9 21.1 1023.8 27.0 1023.8 27.0 HS 28 1.7725 3.3 0.1748 3.2 0.96 1038.7 30.7 1035.4 21.6 1028.5 18.3 1028.5 18.3 HS 69 1.7377 2.6 0.1714 2.4 0.93 1019.6 22.6 1022.6 16.6 1028.9 18.9 1028.9 18.9 HS 74 1.8261 2.6 0.1799 2.5 0.94 1066.2 24.3 1054.9 17.3 1031.5 18.6 1031.5 18.6 HS 92 1.8037 3.6 0.1772 3.5 0.97 1051.4 33.6 1046.8 23.3 1037.2 18.1 1037.2 18.1 HS 66 1.7299 2.7 0.1698 2.5 0.95 1010.8 23.5 1019.7 17.1 1038.9 17.2 1038.9 17.2 HS 16 1.7515 2.3 0.1715 2.1 0.89 1020.2 19.4 1027.7 14.8 1043.7 20.7 1043.7 20.7 HS 67 1.8309 2.0 0.1791 1.9 0.95 1061.9 18.9 1056.6 13.3 1045.8 12.9 1045.8 12.9 HS 71 1.7807 2.3 0.1739 2.1 0.91 1033.6 19.8 1038.4 14.8 1048.6 18.6 1048.6 18.6 HS 24 1.7451 2.4 0.1704 2.3 0.94 1014.1 21.3 1025.3 15.7 1049.4 17.1 1049.4 17.1 HS 45 1.8527 2.4 0.1805 2.2 0.94 1069.9 22.0 1064.4 15.7 1053.0 16.6 1053.0 16.6 HS 96 1.8317 2.1 0.1785 1.9 0.93 1058.7 18.9 1056.9 13.6 1053.2 15.1 1053.2 15.1 HS 7 1.7643 2.0 0.1715 1.9 0.93 1020.3 17.9 1032.4 13.3 1058.2 15.4 1058.2 15.4 HS 109 1.7442 3.3 0.1694 3.1 0.94 1009.0 28.7 1025.0 21.1 1059.3 22.3 1059.3 22.3 HS 29 1.8343 2.8 0.1779 2.5 0.91 1055.7 24.6 1057.8 18.2 1062.1 23.3 1062.1 23.3 HS 22 1.9216 3.2 0.1864 3.1 0.97 1101.8 31.3 1088.6 21.3 1062.4 16.2 1062.4 16.2 HS 2 1.7703 2.7 0.1716 2.5 0.93 1020.6 23.5 1034.6 17.3 1064.4 19.6 1064.4 19.6 HS 39 1.9475 2.4 0.1887 2.2 0.93 1114.3 23.0 1097.6 16.1 1064.5 17.2 1064.5 17.2 HS 102 1.9180 2.6 0.1858 2.4 0.95 1098.3 24.6 1087.4 17.1 1065.5 16.6 1065.5 16.6 HS 9 1.8706 3.7 0.1807 3.5 0.95 1070.9 34.7 1070.7 24.5 1070.4 23.1 1070.4 23.1 HS 1 1.8725 3.0 0.1804 2.9 0.94 1069.4 28.2 1071.4 20.2 1075.6 21.3 1075.6 21.3 HS 37 1.8219 3.0 0.1755 2.9 0.95 1042.6 27.8 1053.4 19.9 1075.8 19.0 1075.8 19.0 HS 3 1.8358 2.2 0.1767 2.1 0.93 1049.0 19.9 1058.3 14.6 1077.7 16.8 1077.7 16.8 HS 20 1.8938 3.4 0.1820 3.2 0.95 1077.7 31.8 1078.9 22.3 1081.5 20.1 1081.5 20.1 HS 17 1.7765 2.2 0.1704 2.0 0.93 1014.4 19.1 1036.9 14.2 1084.6 15.7 1084.6 15.7

HS 13 1.8529 2.7 0.1773 2.6 0.95 1052.0 24.8 1064.5 17.8 1090.1 17.6 1090.1 17.6 HS 8 1.9701 2.5 0.1883 2.4 0.94 1112.0 24.1 1105.4 17.0 1092.3 17.5 1092.3 17.5 HS 61 1.8195 2.2 0.1735 2.0 0.92 1031.3 19.5 1052.5 14.5 1096.7 16.9 1096.7 16.9 HS 108 1.9184 2.8 0.1824 2.7 0.95 1080.0 26.7 1087.5 18.8 1102.6 17.1 1102.6 17.1 HS 97 1.9870 3.8 0.1889 3.6 0.95 1115.2 37.4 1111.1 26.0 1103.1 24.2 1103.1 24.2 HS 53 1.9423 2.3 0.1845 2.2 0.96 1091.4 22.2 1095.8 15.5 1104.5 13.6 1104.5 13.6 HS 65 1.9452 3.3 0.1847 3.2 0.96 1092.7 32.0 1096.8 22.2 1104.8 18.2 1104.8 18.2 HS 107 1.9867 2.0 0.1882 1.8 0.93 1111.5 18.6 1111.0 13.2 1110.0 14.2 1110.0 14.2 HS 25 2.0106 4.9 0.1880 4.8 0.97 1110.8 48.6 1119.1 33.3 1135.2 24.3 1135.2 24.3 HS 36 2.1066 2.4 0.1966 2.3 0.94 1157.0 24.0 1151.0 16.6 1139.6 16.5 1139.6 16.5 HS 106 2.0071 2.1 0.1862 2.0 0.92 1100.7 19.9 1117.9 14.4 1151.5 16.3 1151.5 16.3 HS 60 2.1294 3.2 0.1975 2.9 0.92 1161.8 30.9 1158.4 21.9 1152.0 25.2 1152.0 25.2 HS 84 2.0775 2.5 0.1921 2.4 0.97 1132.5 25.3 1141.4 17.2 1158.4 11.9 1158.4 11.9 HS 80 2.1360 2.2 0.1965 2.1 0.94 1156.7 22.3 1160.5 15.4 1167.6 14.9 1167.6 14.9 HS 62 2.0164 3.2 0.1838 3.1 0.96 1087.6 30.7 1121.1 21.7 1186.4 18.4 1186.4 18.4 HS 73 2.2879 2.7 0.2085 2.5 0.93 1220.7 27.6 1208.6 18.8 1187.0 19.0 1187.0 19.0 HS 31 2.2376 2.5 0.2031 2.3 0.95 1192.0 25.3 1192.9 17.2 1194.5 15.4 1194.5 15.4 HS 78 2.3225 1.8 0.2069 1.7 0.93 1212.5 18.2 1219.2 12.6 1231.1 12.9 1231.1 12.9 HS 40 2.3924 3.4 0.2117 3.2 0.95 1238.0 36.5 1240.3 24.6 1244.3 21.8 1244.3 21.8 HS 21 2.5896 3.0 0.2259 2.8 0.95 1312.9 33.5 1297.7 21.8 1272.6 18.0 1272.6 18.0 HS 88 2.4126 2.6 0.2104 2.5 0.97 1231.1 28.3 1246.3 18.8 1272.9 13.0 1272.9 13.0 HS 72 2.6867 1.9 0.2314 1.8 0.96 1341.6 21.9 1324.8 14.0 1297.6 10.8 1297.6 10.8 HS 99 2.6368 2.9 0.2236 2.8 0.96 1300.9 32.6 1311.0 21.3 1327.5 16.4 1327.5 16.4 HS 18 2.6592 2.3 0.2249 2.1 0.94 1307.9 25.1 1317.2 16.7 1332.3 15.3 1332.3 15.3 HS 51 2.7280 2.1 0.2288 2.0 0.96 1328.0 24.6 1336.1 15.9 1349.1 11.9 1349.1 11.9 HS 52 2.6280 2.4 0.2186 2.3 0.93 1274.4 26.0 1308.5 17.7 1364.8 16.5 1364.8 16.5 HS 94 2.9388 1.8 0.2425 1.7 0.93 1399.9 20.8 1392.0 13.5 1379.8 12.9 1379.8 12.9 HS 5 2.9635 2.5 0.2432 2.4 0.96 1403.3 30.4 1398.3 19.1 1390.6 13.6 1390.6 13.6 HS 55 2.8642 4.1 0.2348 4.0 0.98 1359.8 48.5 1372.5 30.5 1392.4 16.8 1392.4 16.8

HS 86 3.1613 2.0 0.2531 1.8 0.90 1454.3 22.9 1447.7 15.1 1438.2 16.1 1438.2 16.1 HS 59 3.1830 2.2 0.2526 2.1 0.96 1451.7 27.5 1453.0 17.0 1455.0 11.7 1455.0 11.7 HS 41 2.6083 4.2 0.2066 3.1 0.72 1210.6 33.7 1303.0 31.1 1458.4 55.9 1458.4 55.9 HS 50 3.2090 2.7 0.2541 2.6 0.96 1459.5 34.1 1459.3 21.1 1459.1 15.2 1459.1 15.2 HS 63 3.2648 2.7 0.2570 2.5 0.95 1474.6 33.1 1472.7 20.7 1470.0 16.5 1470.0 16.5 HS 6 3.1481 1.8 0.2475 1.7 0.94 1425.4 21.4 1444.5 13.8 1472.8 11.9 1472.8 11.9 HS 47 3.0506 2.4 0.2385 2.2 0.94 1378.7 27.4 1420.4 18.0 1483.4 15.5 1483.4 15.5 HS 76 3.4094 2.8 0.2630 2.7 0.96 1505.0 35.7 1506.6 21.7 1508.7 14.6 1508.7 14.6 HS 89 3.2925 2.9 0.2532 2.8 0.95 1455.2 36.4 1479.3 22.9 1514.0 17.8 1514.0 17.8 HS 23 3.4808 2.3 0.2633 2.2 0.94 1506.7 29.2 1522.9 18.2 1545.4 14.3 1545.4 14.3 HS 57 3.3635 2.4 0.2508 2.3 0.96 1442.6 29.3 1495.9 18.5 1572.4 12.6 1572.4 12.6 HS 75 4.0394 2.3 0.2922 2.2 0.94 1652.7 31.8 1642.2 18.9 1628.7 14.9 1628.7 14.9 HS 83 3.6864 3.3 0.2663 3.2 0.96 1521.9 42.9 1568.4 26.2 1631.5 16.3 1631.5 16.3 HS 70 3.8211 3.3 0.2757 3.2 0.97 1569.9 44.1 1597.2 26.3 1633.3 15.2 1633.3 15.2 HS 81 4.5885 1.9 0.3165 1.8 0.95 1772.8 27.5 1747.2 15.6 1716.6 10.9 1716.6 10.9 HS 30 4.5037 2.8 0.3103 2.7 0.97 1742.2 41.5 1731.7 23.2 1718.9 12.0 1718.9 12.0 HS 35 4.4389 3.6 0.3038 3.4 0.96 1710.0 51.4 1719.6 29.4 1731.3 17.4 1731.3 17.4 HS 33 4.8471 3.7 0.3205 3.6 0.98 1792.0 56.1 1793.1 31.0 1794.3 14.8 1794.3 14.8 HS 46 5.0492 2.6 0.3312 2.5 0.94 1844.0 40.0 1827.6 22.4 1809.0 16.0 1809.0 16.0 HS 4 8.4989 2.3 0.4311 2.2 0.97 2310.9 43.5 2285.8 21.0 2263.4 10.1 2263.4 10.1 HS 26 8.6960 2.7 0.4352 2.6 0.96 2329.0 50.7 2306.7 24.7 2286.9 13.5 2286.9 13.5 HS 87 13.4019 2.4 0.5235 2.2 0.91 2713.9 49.0 2708.4 22.9 2704.3 16.2 2704.3 16.2 HS 100 13.3300 3.1 0.5174 3.0 0.97 2688.0 66.9 2703.3 29.6 2714.8 12.4 2714.8 12.4 HS 49 13.8918 2.4 0.5313 2.2 0.92 2747.0 49.3 2742.4 22.8 2738.9 15.7 2738.9 15.7

Table 7. Stanley

Isotope ratios Apparent ages (Ma) Best age ST-26

Analysis ± ± error ± ± ± ± 207Pb/235U 206Pb/238U 206Pb/238U 207Pb/235U 206Pb/207Pb (%) (%) corr. (Ma) (Ma) (Ma) (Ma) (Ma)

ST 101 0.4086 2.5 0.0535 2.1 0.84 336.0 6.9 347.9 7.3 428.2 30.0 336.0 6.9 ST 27 0.4377 3.2 0.0583 2.7 0.85 365.3 9.6 368.6 9.8 389.2 37.0 365.3 9.6 ST 62 0.5429 2.3 0.0700 2.1 0.88 436.1 8.7 440.4 8.3 462.5 24.1 436.1 8.7 ST 104 0.5841 2.2 0.0754 2.0 0.92 468.5 9.2 467.1 8.2 460.1 18.8 468.5 9.2 ST 35 0.5944 2.3 0.0764 2.1 0.91 474.4 9.5 473.7 8.6 470.5 20.9 474.4 9.5 ST 42 0.5929 2.1 0.0767 1.9 0.93 476.5 8.8 472.7 7.8 454.4 17.2 476.5 8.8 ST 105 0.6188 2.3 0.0778 2.2 0.94 482.9 10.0 489.1 8.9 518.4 17.0 482.9 10.0 ST 43 0.6272 2.5 0.0778 2.4 0.95 483.1 11.1 494.4 9.8 546.7 17.4 483.1 11.1 ST 51 0.6079 2.1 0.0783 1.9 0.94 486.1 9.1 482.2 7.9 463.9 15.5 486.1 9.1 ST 8 0.6087 3.6 0.0783 3.4 0.96 486.3 16.1 482.7 13.8 466.0 23.2 486.3 16.1 ST 19 0.6571 1.8 0.0808 1.6 0.89 501.1 7.6 512.9 7.2 565.4 17.9 501.1 7.6 ST 100 0.6580 2.2 0.0819 2.0 0.90 507.4 9.8 513.4 9.1 540.1 21.7 507.4 9.8 ST 79 0.6776 2.2 0.0844 2.1 0.94 522.1 10.5 525.3 9.2 539.3 16.9 522.1 10.5 ST 31 0.6843 2.5 0.0857 2.4 0.95 530.3 12.2 529.3 10.5 525.0 18.1 530.3 12.2 ST 106 0.7111 1.8 0.0864 1.7 0.94 534.1 8.5 545.4 7.5 592.9 13.3 534.1 8.5 ST 91 0.6982 2.4 0.0864 2.3 0.95 534.3 11.6 537.7 9.9 552.1 15.9 534.3 11.6 ST 70 0.7238 2.4 0.0870 2.2 0.93 537.5 11.4 552.9 10.1 616.9 18.5 537.5 11.4 ST 98 0.7259 2.9 0.0871 2.7 0.93 538.4 13.8 554.1 12.2 619.2 22.4 538.4 13.8 ST 88 0.7077 2.1 0.0876 1.9 0.94 541.6 10.1 543.4 8.8 550.8 16.0 541.6 10.1

ST 76 0.7091 2.1 0.0878 1.9 0.92 542.2 9.9 544.2 8.8 552.5 18.1 542.2 9.9 ST 49 0.7120 3.0 0.0887 2.8 0.95 547.6 14.8 545.9 12.6 539.0 20.9 547.6 14.8 ST 5 0.7426 1.9 0.0888 1.7 0.92 548.2 9.1 563.9 8.2 627.9 16.1 548.2 9.1 ST 86 0.7160 2.6 0.0889 2.4 0.94 549.0 12.8 548.3 11.0 545.5 19.1 549.0 12.8 ST 110 0.7307 1.9 0.0904 1.8 0.94 557.9 9.7 556.9 8.3 553.0 14.7 557.9 9.7 ST 54 0.7541 2.6 0.0925 2.5 0.95 570.4 13.5 570.6 11.4 571.2 18.0 570.4 13.5 ST 59 0.7785 2.1 0.0933 1.9 0.89 574.9 10.2 584.6 9.2 622.8 20.2 574.9 10.2 ST 84 0.7890 1.9 0.0957 1.7 0.92 589.2 9.6 590.6 8.3 596.2 16.2 589.2 9.6 ST 4 0.7793 2.4 0.0959 2.3 0.95 590.2 12.9 585.1 10.7 565.3 15.8 590.2 12.9 ST 7 0.8022 2.1 0.0971 1.9 0.93 597.6 11.1 598.0 9.4 599.7 16.8 597.6 11.1 ST 41 0.8092 2.8 0.0979 2.7 0.94 601.9 15.4 602.0 12.9 602.6 20.4 601.9 15.4 ST 81 0.8411 2.2 0.1006 2.0 0.93 617.7 11.8 619.7 10.0 627.2 16.8 617.7 11.8 ST 18 0.8713 1.8 0.1018 1.6 0.91 624.8 9.6 636.3 8.4 677.3 16.0 624.8 9.6 ST 83 0.8702 2.4 0.1027 2.3 0.94 630.3 13.5 635.7 11.3 654.8 17.1 630.3 13.5 ST 44 0.8912 2.9 0.1035 2.7 0.93 635.0 16.3 647.0 13.9 689.3 22.7 635.0 16.3 ST 107 0.9071 2.2 0.1054 1.9 0.88 646.1 11.8 655.5 10.6 687.8 22.3 646.1 11.8 ST 47 0.9179 3.4 0.1058 3.3 0.96 648.2 20.1 661.3 16.6 706.2 21.4 648.2 20.1 ST 22 0.8991 2.5 0.1059 2.3 0.94 648.6 14.3 651.3 11.9 660.4 18.6 648.6 14.3 ST 50 0.9019 2.3 0.1061 2.2 0.96 649.9 13.5 652.8 10.9 662.6 13.8 649.9 13.5 ST 46 1.0726 2.7 0.1206 2.6 0.94 733.9 17.8 740.0 14.3 758.5 19.3 733.9 17.8 ST 87 1.1956 2.7 0.1296 2.6 0.96 785.5 19.3 798.6 15.1 835.1 16.6 785.5 19.3 ST 34 1.2595 2.7 0.1309 2.6 0.97 793.0 19.5 827.7 15.3 922.0 13.7 793.0 19.5 ST 13 1.1803 2.2 0.1310 2.0 0.93 793.5 15.1 791.4 12.0 785.7 17.4 793.5 15.1 ST 24 1.2802 2.7 0.1384 2.5 0.94 835.4 19.7 836.9 15.2 841.0 18.9 835.4 19.7 ST 67 1.3686 2.1 0.1408 2.0 0.93 848.9 15.9 875.6 12.6 943.6 15.8 848.9 15.9 ST 39 1.3079 1.5 0.1410 1.4 0.90 850.4 11.1 849.2 8.8 846.0 13.6 850.4 11.1 ST 99 1.3603 2.1 0.1451 2.0 0.96 873.6 16.3 872.0 12.2 868.1 11.9 873.6 16.3 ST 92 1.4350 2.4 0.1498 2.3 0.97 899.6 19.7 903.6 14.5 913.5 12.6 913.5 12.6 ST 30 1.4085 3.5 0.1448 3.3 0.93 871.5 27.0 892.5 21.0 945.0 25.7 945.0 25.7

ST 103 1.5210 2.0 0.1553 1.9 0.96 930.7 16.8 938.9 12.4 958.0 11.8 958.0 11.8 ST 65 1.6578 2.9 0.1644 2.8 0.96 981.0 25.5 992.5 18.5 1018.0 17.1 1018.0 17.1 ST 17 1.6629 2.1 0.1640 2.0 0.94 979.2 18.0 994.5 13.3 1028.3 14.1 1028.3 14.1 ST 94 1.6615 2.1 0.1638 2.0 0.93 978.0 17.9 994.0 13.5 1029.3 16.2 1029.3 16.2 ST 97 1.7489 2.1 0.1719 2.0 0.96 1022.4 19.3 1026.8 13.8 1036.1 12.0 1036.1 12.0 ST 23 1.8104 2.5 0.1779 2.4 0.94 1055.2 23.1 1049.2 16.6 1036.7 18.2 1036.7 18.2 ST 102 1.7100 2.4 0.1673 2.3 0.96 997.0 21.0 1012.3 15.1 1045.5 12.9 1045.5 12.9 ST 82 1.7803 2.1 0.1735 1.9 0.94 1031.4 18.5 1038.3 13.4 1052.9 13.9 1052.9 13.9 ST 58 1.7622 2.2 0.1717 2.1 0.94 1021.6 19.4 1031.7 14.2 1053.0 15.3 1053.0 15.3 ST 61 1.8396 2.5 0.1792 2.4 0.97 1062.7 23.5 1059.7 16.4 1053.7 13.1 1053.7 13.1 ST 89 1.8573 2.8 0.1807 2.7 0.98 1071.1 27.0 1066.0 18.5 1055.8 12.5 1055.8 12.5 ST 15 1.7000 2.4 0.1653 2.3 0.96 986.3 21.4 1008.5 15.6 1057.1 13.6 1057.1 13.6 ST 37 1.8404 2.0 0.1779 1.9 0.92 1055.6 18.2 1060.0 13.3 1069.0 15.8 1069.0 15.8 ST 29 1.8225 2.4 0.1760 2.3 0.96 1045.3 21.8 1053.6 15.4 1070.8 13.6 1070.8 13.6 ST 1 1.9574 2.0 0.1863 1.9 0.94 1101.5 19.1 1101.0 13.4 1100.0 13.1 1100.0 13.1 ST 21 1.8565 2.5 0.1761 2.4 0.97 1045.8 23.5 1065.8 16.6 1106.9 12.4 1106.9 12.4 ST 48 2.0462 2.1 0.1901 2.0 0.94 1121.7 20.4 1131.0 14.4 1149.0 13.9 1149.0 13.9 ST 38 2.2408 1.9 0.2055 1.8 0.95 1205.0 20.3 1193.9 13.6 1174.0 11.6 1174.0 11.6 ST 10 2.2242 1.8 0.2029 1.7 0.95 1191.0 18.7 1188.7 12.8 1184.5 11.7 1184.5 11.7 ST 95 2.2658 2.2 0.2054 2.1 0.95 1204.2 23.4 1201.7 15.8 1197.2 13.4 1197.2 13.4 ST 69 2.7072 2.3 0.2302 2.1 0.93 1335.8 25.5 1330.4 16.8 1321.8 15.8 1321.8 15.8 ST 2 3.8203 2.3 0.2752 2.3 0.97 1567.0 31.5 1597.0 18.8 1636.9 10.9 1636.9 10.9 ST 32 3.8424 3.2 0.2699 2.5 0.76 1540.2 33.7 1601.7 26.0 1683.5 38.5 1683.5 38.5 ST 20 4.7742 2.2 0.3192 2.1 0.97 1785.6 33.1 1780.4 18.5 1774.3 10.4 1774.3 10.4 ST 64 5.3579 3.0 0.3381 2.9 0.96 1877.3 46.6 1878.1 25.6 1879.0 15.6 1879.0 15.6 ST 3 5.3326 3.3 0.3357 3.2 0.97 1865.7 51.5 1874.1 28.0 1883.4 13.7 1883.4 13.7 ST 55 5.2274 3.1 0.3287 3.0 0.98 1832.1 47.7 1857.1 26.0 1885.2 10.9 1885.2 10.9 ST 14 5.3943 2.1 0.3266 2.0 0.95 1822.0 31.1 1884.0 17.7 1952.9 11.8 1952.9 11.8 ST 40 5.5547 2.5 0.3362 2.4 0.96 1868.5 38.1 1909.1 21.1 1953.5 12.3 1953.5 12.3

ST 72 5.2698 2.9 0.3188 2.8 0.96 1783.9 43.8 1864.0 24.9 1954.5 14.0 1954.5 14.0 ST 68 5.9491 1.9 0.3574 1.8 0.95 1969.6 30.9 1968.4 16.7 1967.1 11.1 1967.1 11.1 ST 33 5.4740 2.6 0.3274 2.4 0.95 1825.9 38.6 1896.5 21.9 1974.8 14.3 1974.8 14.3 ST 73 6.5156 2.4 0.3789 2.3 0.96 2071.0 41.3 2048.0 21.4 2025.0 12.0 2025.0 12.0 ST 45 5.2577 3.4 0.3041 3.3 0.97 1711.5 49.7 1862.0 29.0 2034.5 13.6 2034.5 13.6 ST 28 6.4691 3.3 0.3691 3.2 0.97 2025.1 56.0 2041.7 29.1 2058.5 13.1 2058.5 13.1 ST 11 6.8035 2.6 0.3843 2.5 0.97 2096.2 45.4 2086.2 23.1 2076.3 10.7 2076.3 10.7 ST 93 6.9573 2.4 0.3889 2.3 0.97 2117.7 41.7 2106.0 21.2 2094.6 10.8 2094.6 10.8 ST 25 7.1013 2.2 0.3894 2.1 0.96 2119.8 38.7 2124.2 19.9 2128.4 11.5 2128.4 11.5 ST 80 7.4059 2.9 0.3931 2.7 0.96 2137.3 49.9 2161.7 25.7 2184.9 14.7 2184.9 14.7 ST 85 8.1009 2.3 0.3890 2.1 0.92 2118.2 38.2 2242.4 20.7 2357.6 15.2 2357.6 15.2 ST 77 9.8514 2.0 0.4413 1.9 0.94 2356.5 37.2 2421.0 18.5 2475.6 11.4 2475.6 11.4 ST 90 10.2948 2.3 0.4478 2.3 0.96 2385.6 44.9 2461.6 21.7 2525.0 11.2 2525.0 11.2 ST 26 19.7288 2.3 0.6309 2.2 0.96 3153.1 54.1 3078.2 21.8 3029.6 9.7 3029.6 9.7 ST 78 22.4746 2.4 0.6344 2.3 0.97 3166.9 57.3 3204.5 22.9 3228.0 8.4 3228.0 8.4

Concordia Plots

Normal Concordia Plot

Tara-Wasserburg Concordia Plot

VITA

Personal Background Preston Reeves McGuire Ruidoso, New Mexico Born January 10, 1992, Albuquerque, New Mexico Son of Reeves and Jane McGuire

Education Bachelors of Science in Petroleum Geology, 2014 Western State Colorado University, Gunnison, Colorado

Masters of Science in Geology, 2017 Texas Christian University, Fort Worth, Texas

Experience Geoscience Intern, Summer 2014 Paragon Geophysical Services, Wichita, Kansas

Geoscience Intern, Summers 2015 and 2016 Antero Resources, Denver, Colorado

Professional Memberships American Association of Petroleum Geologists Dallas Geological Society Fort Worth Geological Society

Geological Society of America

ABSTRACT

U-Pb DETRITAL ZIRCON SIGNATURE OF THE OUACHITA OROGENIC BELT

Preston Reeves McGuire, M.S., 2017 School of Geology, Energy, & the Environment Texas Christian University

Thesis Advisor: Dr. Xiangyang Xie Committee Members: Dr. Helge Alsleben and Dr. Elizabeth Petrie

The Late Paleozoic Ouachita fold-and-thrust belt extends from the southern terminus of the Appalachian thrust belt in eastern Mississippi up through central Arkansas, southeastern Oklahoma, and Texas terminating in northeastern Mexico. A series of Carboniferous foreland basins were formed sequentially to the thrust front. The interaction between the Laurentian craton and the Appalachian-Ouachita orogenic belts controlled sedimentation in the southern midcontinent region throughout the Paleozoic. In contrast to the Appalachian orogenic belt to the east, the Ouachita orogenic belt and associated sediments remain poorly documented and less constrained. In this study, seven Ordovician to Mississippian aged clastic units from the Ouachita Mountain in central Arkansas were sampled and tested using U-Pb detrital zircon geochronology. Three major age peaks are prominent, including the Grenville Province (~0.95- 1.2 Ga), the Granite-Rhyolite Province (~1.3-1.5 Ga), and the Superior Province (>~2.5 Ga) in Ordovician to Silurian aged rocks. A change in this signature becomes clear at the beginning of the Carboniferous from Early Mississippian Stanley Group samples showing the additional Paleozoic age peak (~490-520 Ma) potentially derived from the Appalachian orogenic belt to the

east, and/or from peri-Gondwanan terranes accreted to Laurentia just before the collision with Gondwana. This stratigraphic variation of detrital zircon age signature suggests that the transition from a passive to an active margin in the Ouachita trough started, at the latest, in early Mississippian times. Results of this study is the first systematic study of the U-Pb detrital zircon signature of the Ouachita orogenic belt and have important implications in sediment dispersal, provenance interpretations, and paleogeography reconstructions in North America, especially in the southern mid-continent and surrounding areas.