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Guidebook for Pre-Meeting Field Trip to Newark Basin

Guidebook for Pre-Meeting Field Trip to Newark Basin

GeoPRISMS Planning Workshop for the East African System Morristown, 25 – 27 October, 2012

Guidebook for Pre-Meeting Field Trip to

Roy W. Schlische and Martha Oliver Withjack Department of Earth & Planetary Sciences, Piscataway, NJ 08854-8066, USA [email protected], [email protected]

Purpose of Field Trip

To provide a brief overview of the eastern North American (ENAM) rift system by observing the structure, , and igneous rocks of the Newark rift basin. We will discuss the influence of pre-existing zones of weakness on rift-basin development, the considerable spatial and temporal variability of syn-rift deposition near the border-fault zone, and the absence of rift- related igneous activity except for that associated with the short-lived CAMP (Central Atlantic Magmatic Province).

List of Stops

STOP 1. Durham Furnace, PA. Highly deformed carbonates (pre-rift rocks) exposed in the footwall of the border-fault zone of the Newark basin.

STOP 2. Kintnersville, PA. Small normal faults near the border-fault zone of the Newark basin; playa-lacustrine syn-rift strata with evaporites in the .

STOP 3. County Park, near Upper Black Eddy, PA. sheet related to the Central Atlantic Magmatic Province (CAMP); shallow-water lacustrine syn-rift strata of the Passaic Formation affected by contact metamorphism () and fracturing.

STOP 4. (Optional) Pebble Bluff, near Milford, NJ. Alluvial-fan and deep-water lacustrine facies of the Passaic Formation in hanging wall of border-fault zone.

Introduction

Eastern is a natural laboratory for studying rift basins and passive-margin development. It hosts one of the world’s largest rift systems (the eastern North American rift system), one of the world’s oldest intact passive margins, and one of the world’s largest igneous provinces (the Central Atlantic Magmatic Province, CAMP). Additionally, seismic-reflection profiles, field exposures, drill-hole data, and vitrinite-reflection data provide a wealth of information about the tectonic and depositional processes associated with rifting, breakup, and

page 1 the early stages of seafloor spreading.

During early Mesozoic time, a massive rift zone developed within the Pangean (insert, Fig. 1). The breakup of Pangea splintered this rift zone into extinct fragments, each now separated and preserved on the passive margins of eastern North America, northwestern , and Europe. The fragment on the North American margin, called the eastern North American (ENAM) rift system, consists of a series of exposed and buried rift basins extending from northern Florida to the eastern Grand Banks of Canada (e.g., Manspeizer and Cousminer, 1988; Olsen et al., 1989; Schlische, 1993, 2003; Withjack et al., 1998) (Fig. 1). It is a large rift system, affecting a region up to 500 km wide and 3000 km long. Withjack and Schlische (2005) and Withjack et al. (2012a) divided the eastern North American rift system into three segments based on tectonic history (Fig. 1). Rifting was underway in all three segments by Late time. The end of rifting (and presumably the beginning of seafloor spreading), however, was diachronous, occurring first in the southeastern (latest Triassic), then in the northeastern United States and southeastern Canada (Early ), and finally in the Grand Banks (Early ) (Withjack et al., 1998, 2012a; Withjack and Schlische, 2005; Schettino and Turco, 2009).

Newark rift basin

The Newark rift basin lies within the central segment of the ENAM rift system (Fig. 1). It is one of the largest and most thoroughly studied of the ENAM rift basins with abundant field, seismic, core, borehole, and vitrinite-reflectance data available to constrain its development (Fig. 2).

Stratigraphy of Newark rift basin

The stratigraphy of the Newark rift basin consists of the Stockton, Lockatong, and Passaic formations of age and the overlying and interbedded sedimentary rocks of latest Triassic to Early Jurassic age (i.e., the Orange Mountain , , Preakness Basalt, , Hook Mountain Basalt, and ) (e.g., Olsen et al. 1996a; Fig. 3). Most syn-rift strata accumulated in a lacustrine setting and exhibit a pervasive cyclicity in sediment fabrics, color, and total organic carbon (from microlaminated black to extensively mudcracked and bioturbated red mudstone) (e.g., Olsen, 1986, Olsen et al., 1996a). We will see evidence of these sedimentary features at Stops 2, 3 and 4. Individual members of the stratigraphic units have great lateral extent and continuity and have been traced throughout much of the Newark basin (e.g., McLaughlin, 1948; Olsen, 1988); a prominent example is the Perkasie Member of the Passaic Formation (Fig. 2) (Stop 4). Biostratigraphy indicates that the preserved syn-rift strata in the Newark basin range in age from Carnian (Late Triassic) to (Early Jurassic) (e.g., Cornet and Olsen, 1985; Olsen et al., 2011). Igneous rocks (e.g., basaltic lava flows, diabase sheets, and dikes) in the Newark basin are associated with the Central Atlantic Magmatic Province (CAMP), one of the world’s largest igneous provinces (e.g., McHone, 1996, 2000; Marzolli et al., 1999; Hames et al., 2003) (Fig. 4). CAMP-related igneous activity occurred during the very latest Triassic and earliest Jurassic (~200 Ma) (see Olsen et al., 2003, 2011 and references therein). We discuss additional aspects of CAMP at Stop 3.

page 2

Structure and tectonic evolution of Newark rift basin

A series of NE-striking, SE-dipping, right-stepping faults bound the Newark basin on the northwest (Fig. 5a). The bounding faults are subparallel to thrust faults present in pre-rift rocks surrounding the basin. Several large intrabasin faults also dissect the basin. Most syn-rift strata dip 10 - 15° NW toward the border-fault zone. Near many of the border and intrabasin faults, however, the syn-rift strata are warped into a series of anticlines and synclines whose axes are mostly perpendicular to the adjacent faults (i.e., transverse folds; e.g., Wheeler 1939; Schlische 1992, 1995). The Newark basin, like many other rift basins of the eastern North American rift system, underwent significant post-rift deformation including much of the tilting and folding of the syn-rift strata (e.g., Sanders, 1963; Faill, 1973, 1988; Withjack et al., 1998; Schlische et al., 2003; Withjack et al., 2010). Furthermore, the basin underwent significant (locally more than 6 km) after rifting (e.g., Steckler et al., 1993; Malinconico, 2010; Withjack et al., 2012b).

Seismic line NB-1, located near the route of this field trip, images the subsurface geometry of the Newark basin. The seismic line shows that a major SE-dipping fault zone with normal separation bounds the basin on the northwest (Fig. 5b). The fault zone, characterized by a series of high- amplitude reflections, is relatively planar and has a dip magnitude of ~ 30°. Using core data, Ratcliffe et al. (1986) demonstrated that this fault zone is a mylonitic Paleozoic thrust fault reactivated during rifting; this is consistent with the relatively low-angle dip of the border fault. The seismic data show that the syn-rift strata dip ~10 - 15° toward the northwest. Furthermore, the (exposed at the surface) and an unexposed older unit (which onlaps Paleozoic pre-rift strata) thicken toward the border-fault zone, indicating that faulting and deposition were coeval (i.e., these units are growth deposits). Field and core data indicate that the Lockatong and Passaic formations also exhibit subtle thickening toward the border-fault zone. Furthermore, all sedimentary formations contain conglomeratic facies where present adjacent to the border-fault zone (see material for Stop 4).

As the Newark rift basin developed from Late Triassic to Early Jurassic time, its geometry changed substantially (Fig. 6; Withjack et al., 2012b). Initially, the basin was narrow (< 25 km) and asymmetric, bounded on one side by a border-fault zone. The older syn-rift strata show significant thickening toward the fault zone. As rifting progressed, the basin, although still fault- bounded, became much wider (possibly > 100 km), deeper (up to 10 km), and less asymmetric; syn-rift strata exhibit subtle thickening toward the border-fault zone. Subsequent post-rift deformation and erosion (up to 6 km) significantly reduced the size of the Newark basin.

page 3 Palaeozoic contractional structure

Early Mesozoic rift basin bounded by extensional fault + Northern ++ East Coast Magnetic Anomaly + + Blake Spur Magnetic Anomaly + (~165-170 Ma) Continental Oceanic crust crust

Newfoundland fracture zone North Central America Newark + + + basin + + + + North + + + Southern + + + N + + + + + + M-25 (~155 Ma) + ~400 km + + + + + + + Europe + + + + + North ? America + + Rift + Zone ? + South Africa + America +

Fig. 1: Tectonic setting of the Mesozoic eastern North American rift system showing the main segments of the rift system (southern, central, and northern). The geometry of the offshore rift basins and those below the post-rift coast- al plain is schematic. The boundary between the southern and central segments is diffuse; the boundary between the central and northern segments corresponds to the Newfoundland fracture zone and the large fault zone that bounds the Fundy basin on the north. Modified from Withjack & Schlische (2005). Inset shows rift zone within the Pangean supercontinent (modified from Olsen 1997).

page 4 m s i s y k t r r s e e N e s g 5 r r t e e a u u 2 t t i e P i N R l l e s = i = = s v n a i N R s e l P e u r l c t i i o t o T n c = h 1 T e A # e l P l t r I i n e v B C o o n s s t K r o n B e t B i t e t c s r o N m n e i a b r o a W M P S = C = = = = M P S W C 1 - B n N o i s u r s t e n i i c e a f s a c i b t i a i r C d e c m i o s l s k g a P n r n o u o i C J t ) n c n o e i r t w i a o d t n n p k i e d e m r s a e e n h v r a i w P O g ( r t l e a t l d s n l a a t o l n o r s i n B t e n n o a g n u o t i a b i n l o o & t n o i a B t i i i i a f t t a m d t m a a c n s r e d a a l t a i i k m e a m o n a M r a P m m r o b m t F B r r u o r n e f o z i n e o o o F o o s g s F o t o u k i l F F a s F n M e n t e o y n k e u n o c e r i o o c a e i t l o l d M n t a e l l - t c a i g a a f k k P t a n k a r m e s v k n l a c = r t t o o s c g P l a s w k e o o u r n o o r a t e o o a n : s P F a i o B H T P F O P L S f s k b d c l k c a i n a c o c d i u r n o k o r o t o P c f i i z t b i f - s s r o i - n n s r e t i - e a a s s t l e r o r a x a u

P P

B E P J

c i s s a r u J c i s s a i r T e t a L

y l r a E

s s k k c c o o r r t t f f i i r r n n y y S S

Fig. 2. Geologic map of the Newark rift basin showing distribution of sedimentary formations, lava flows, and dia- base intrusions; locations of borehole and core sites; and seismic-line NB-1. Only the largest Paleozoic contractional faults are shown. Box shows area of field-trip stops. Modified from Withjack et al. (2012b) based on Schlische (1992), Olsen et al. (1996a), and Schlische & Withjack (2005a).

page 5 Formations Cores & & Selected Magnetic Members Polarity Lithology Geologic Age meters feet Ma Boonton c i

Fm. s s n a a Hook Mt. i 200.8 Black 2000 r Basalt g u n

Gray E J a

Sedimentary rocks t Towaco Fm. C Basalt t Purple y A e l r Red H Preakness 1000 a Basalt E Feltville Fm. Orange Mt. Basalt 0 e 201.4 l l i v s n i t r n a 1000 a i M t e a h R

n 2000 o t s e W 3000

t 1000 e s r e

m 4000

Passaic o

Fm. S c i

5000 s

s 212.2 a i s r r T e

Fig. 3. Stratigraphy of the Newark basin. g e t

6000 t u

The lithologic column is a composite sec- a R tion based on seven Newark Basin Coring L Perkasie Project cores (see geologic map for 2000 Stops 3, 4 7000 locations) and several cores from the Stop 2 Army Corps of Engineers (ACE). For the e l l i

core-based magnetic-polarity stratigra- n v a s i

u 8000 phy (Kent et al., 1995), black represents r t i o T

normal polarity. In all cored sections, all N sedimentary formations (with the excep- 217.8 tion of parts of the Stockton Formation) 9000 are lacustrine, and exhibit a pervasive cyclicity related to lake-depth fluctuations y r 3000

(black is deepest water, red is shallowest). Lockatong e

s 10000 Based on global correlations, the Trias- Fm. r u sic-Jurassic boundary is currently placed N in the lower Feltville Formation. Previ- ously, it was placed just below the Orange 11000 Mountain Basalt, coincident with the level 222.4 of the end-Triassic mass extinction (see n

o 12000 Olsen et al., 2011 for a full discussion). t e

The geologic ages are based on radiomet- c n i ric dates of the lava flows coupled with r Milankovitch cyclostratigraphy. Modified P ~228 Stockton 4000 13000 from Withjack et al. (2012b) based on Fm.

Olsen et al. (1996a, 2011), and Olsen and n a i

Whiteside (2008). n 14000 r a C ~233

page 6 e c n i v o r P c i t a m P g a M A M C A c S i U t . E n . S a l t A l a r t n e C . s e a d d ) l k k e 7 s e i n c m a s i f 0 l o i f o o e o g 0 r r r B d r n d n f 2 e o i c c e ( e = o i e r t t d a n v . t P M i u l H e D a n t o i s h . c d B a e a l f t u l = i u n c t t r ; p c i d r M d e D o t n s A O , e e i o P m d x ; a S e d s N p k - s e n b d u M M a o i a 0 a r n N r . b l d k s t A r 0 t N ) u r n e n n d e 4 a t C i A 0 a t o E a i n ~ n i s 0 e h w a h s a e d a 0 r e g n v g e n 2 e i W E i e r N ( a t s S w n H d A - x i = e u a l n e i r d = n s N W t a a r t n o e A r f ; e n N ) a t i i k : n H b i r 0 , n i I d e - c d 0 e P s r , n W n 0 . a M ) e a C e a y S 5 M 2 b s r 0 - s c s ( = t 0 n i a A 2 ( E d n e r o A e b e t h f r C o h t N a n a c i a d o H A s i f t u c i f o h l t e d i d l , t t h d o C a o - a r s c r r i n s t a H s S e ; a a c v o e s a n c c & i B n i e b r e k o m o N s i d t c r H r i h a M a ) s s p j A t t e o b h r = h t 5 a a i s u y t b r m n m s ) 0 W l b r H b i o 5 r o u e A i 0 m 9 A o r ; o C 9 r s r k r J . 2 1 f f e n t e i n e h , ( s d . l n s i t l p y e u k i i e a s f l o o i e i e u t d i h d d r h e a t h o p o b t n D a h l u M b c c e l S O a . u n C ( s u E h , y i i , n t r l C f a s d t o s f h s i c o n n = e i c i s o n u k r . s p C S n i o ) e p F a a e ; c 4 t D a b m & e = u x 0 . M r t a A e F M f 0 k a . i e c a t . 2 c ; t a h r f i ( e t a b i n a 4 r j i r . y l g r 4 l . e s h - o n n P . t a g a n i a a i m N g t y b i P m W e F A s n F i page 7 f

Conglomeritic facies Diabase Boonton Formation c Fig. 5a. Simplified geologic map of Newark basin showing location of seismic i Hook Mountain Basalt y s l s r

line NB-1 and highlighting folds adjacent to the border-fault system and a a Towaco Formation r s E u intrabasinal faults. Modified from Withjack et al. (2012b). k J Preakness Basalt c o

r Feltville Formation t f i c i r Orange Mountain Basalt - s s n a y

i Passaic Formation r S T Pk=Perkasie Member e

t Form-line of bedding a L Stockton Formation Pre-Stockton

Pre-rift rocks: Paleozoic & older 5 km Cabot #1 NW proj. 2.3 km 1:1 at 5 km/s SE 0

1 ) . 2 c e s ( T T 3 W T Flemington-Furlong fault 4 Reflections from faults or shear zones in pre-rift rocks Basin-bounding fault zone 5 Seismic Line NB-1 Fig. 5b. Interpretation of seismic line NB-1 from Newark basin. Modified from Withjack et al. (2012b).

page 8 NW SE

5 km a. End of syn-rift deposition

b. After deposition of Passaic Fm.

c. After deposition of Lockatong Fm.

d. After deposition of Stockton Fm.

e. After deposition of unexposed syn-rift unit

Fig. 6. Restoration of the Newark ~15 km of basin, showing the progressive lengthening widening of the basin during rift- ing. See Figure 5b for basin geom- etry after post-rift deformation and f. Onset of syn-rift deposition erosion. From Withjack et al. (2012b).

page 9 ROAD LOG and STOPS (see Figs. 7 and 8)

START. Hyatt Morristown, 3 Speedwell Ave., Morristown, NJ 07960. The hotel is located adjacent to the Ramapo border fault of the Newark basin, which separates Early Jurassic syn- rift rocks from Proterozoic pre-rift rocks. The border fault is marked by a fault-line scarp visible on shaded-relief maps.

Road log to Stop 1. Travel time: ~1 hour, 8 minutes Go… Total 1. Head south on Speedwell Avenue 0.2 mi 0.2 mi 2. Turn left onto County Road 510 0.8 mi 1.0 mi 3. Slight left onto Madison Avenue 0.1 mi 1.1 mi 4. Slight right to merge onto I-287 South 14.4 mi 15.5 mi 5. Take exit 21B to merge onto I-78 W toward Easton, PA 18.9 mi 34.5 6. Take the exit for NJ-173W, bear left at end of ramp for NJ-173W 0.2 mi 34.7 7. At traffic circle, take 2nd exit onto Pattenburg Road / County Road 614. 4.1 mi 39.8 mi We are now traveling southwest, parallel to the border fault located <1 km to the NW. 8. Turn left onto Route 631 / Little York Mt. Pleasant Road which becomes 0.4mi 40.2 mi Spring Mills Road 9. Bear right onto County Road 614 / Spring Mills Road 2.3 mi 42.5 mi 10. Turn left onto County Road 519 / Milford Warren Glen Road 2.3 mi 44.8 mi 11. Turn right on Bridge Street and cross Delaware River 0.3 mi 45.1 mi 12. Turn right onto PA-32 North / River Road 4.5 mi 49.6 mi 13. Turn right on PA-611 North / Easton Road / River Road. Lehnenberg 2.0 mi 51.6 mi Road marks the location of the border fault. After passing Route 212 (Durham Road), continue 0.2 miles to parking area for Delaware Canal (gas station is just north of parking area). Walk south along the canal path to view the outcrop.

Stop 1: Pre-rift rocks (Cambrian carbonates), Route 611, Durham Furnace, PA

Outcrop-scale folding affects the Cambrian carbonate sedimentary rocks at Stop 1 (Fig. 9). The lithology and sedimentary features (i.e., mudcracks) indicate that the rocks were deposited in shallow marine conditions, likely associated with an early Paleozoic passive margin. Anticlines and synclines with steeply dipping and overturned limbs are present. Cleavage is widely spaced and converging downward in the massive competent units and closely spaced and diverging downward in the less competent units. This deformation is related to shortening produced during one or more of the Appalachian orogenies that preceded rifting.

Stop 1 is within the footwall of the Newark rift basin about 2 km to the NW of the NE-striking, SE-dipping border fault of the basin. As we proceed to Stop 2, we will travel from the footwall into the hanging wall of the Newark rift basin, crossing the basin-border fault (Fig. 10). Seismic data (NB-1, Fig. 5b) together with core data (Ratcliffe et al., 1986) show that the border fault of the Mesozoic Newark rift basin dips ~25 to 30° to the SE and parallels Paleozoic thrust faults.

page 10 The anomalously gentle dip of the basin-border fault and its orientation relative to that of the adjacent Paleozoic thrust faults suggest that it is a reactivated pre-existing structure. Restorations (Fig. 6) show that the border fault of the Newark rift basin had more than 10 km of displacement during rifting from Late Triassic to earliest Jurassic time.

Road log to Stop 2. Travel time: ~4 minutes Go… Total 14. Turn around and head south on Route 611. After ~2.0 miles, bear right 3.1 mi 3.1 mi to stay on PA-611 South. After passing Traugers Crossing Road, pull off onto the wide shoulder on the right. Large exposure is on the left (northbound side) of road. Be careful crossing the road.

Stop 2: Normal Faults in Passaic Formation, Route 611, Kintnersville, PA

A set of meter-scale normal faults (Fig. 11) cuts red mudstone of the middle Passaic Formation. The normal faults strike ~030° and generally dip 40°-50° SE. Slickenlines are steeply raking, indicating predominantly dip-slip movement. Like most of the larger intrabasinal faults in the Newark rift basin, these small faults are oblique to the strike of segments of the border-fault zone (the strike of the nearest segment of the border-fault zone is ~060°). This fault pattern is indicative of oblique extension (e.g., Schlische et al., 2002), i.e., the extension direction was not perpendicular to the strike of the border-fault zone. The geometry of the intrabasinal faults and the strike of the earliest Jurassic CAMP-related diabase dikes suggest that the extension direction was WNW-ESE.

Fault 2 has the smallest displacement and narrowest zone of breccia and gouge; fault 4 has the largest displacement and widest zone of breccia and gouge. These faults obey an approximately linear scaling relationship between fault-zone thickness and fault displacement (e.g., Hull, 1988; Knott, 1994; Knott et al., 1996; Fig. 11d). The sequence going from fault 2 to 3 to 1 to 4 likely reflects stages in the evolution of normal faults with increasing displacement; this involves the linkage of originally isolated segments and the widening of the fault zone.

According to Withjack and Olsen (1999), the exposure belongs to the upper part of Member K of the Passaic Formation (nomenclature of Olsen et al., 1996a). Deposition occurred mostly in playas. A prominent bed contains vugs that were once filled with evaporite . Silt bands likely represent slightly deeper or more permanent shallow lakes. Red beds similar to those outcropping here account for more than 80% of the Passaic Formation.

Although this outcrop is only about 3 km from the border fault, the sedimentary rocks are remarkably fine grained. Two possibilities account for this observation: (1) The hanging-wall block and axial sources contributed more sediment than the footwall block (Fig. 12a), as in many modern rift basins (e.g., Gawthorpe and Leeder, 2000). (2) The present-day border fault of the basin was not the outermost border fault during deposition (Fig. 12b). In Late Triassic time, coarser sediments accumulated in the hanging walls of border faults located to the NW of the present-day border fault. Subsequent erosion removed these coarse-grained strata and exposed the Paleozoic and rocks. Vitrinite reflectance data indicate that 4 - 6 km of erosion

page 11 occurred in the vicinity of this outcrop (Steckler et al., 1993; Malinconico, 2010; Withjack et al., 2012b; Fig. 12c).

Road log to Stop 3. Travel time: ~11 minutes Go… Total 15. Continue south on PA-611 0.7 mi 0.7 mi 16. Turn left (at traffic light) onto Center Hill Road 3.2 mi 3.9 mi 17. Turn right on Ringing Rocks Road. Entrance to Ringing Rocks park is 0.6 mi 4.5 mi on the left. Follow the trail on foot to the boulder field. Then continue down trail to the waterfall.

Stop 3: Ringing Rocks County Park, Upper Black Eddy, PA (Fig. 13)

The boulder field in Ringing Rocks County Park contains rocks of the Coffman Hill diabase (dolerite). The boulders exposed to abundant sunlight do “ring” when struck with a hammer! The Coffman Hill diabase is the erosional remnant of a folded intrusive sheet. The geologic map (Figs. 2 and 8) shows that strata consistently dip toward the diabase, indicating that the diabase sheet and intruded strata define a doubly-plunging syncline (or basin). Contact metamorphic rocks of the Passaic Formation underlying the intrusive sheet are exposed at the waterfall (at the end of the hiking trail). These gray rocks are relatively fine-grained (mostly mudstone with some ). Mudcracks and ripple marks suggest that these strata accumulated in very shallow lakes. Although gray rocks are typically associated with deeper-water deposits, in this case, the gray color results from contact metamorphism. The hornfels contains well-developed subvertical joints.

The Newark rift basin contains many other diabase sheets (Fig. 2), many of which, like the Coffman Hill diabase, are folded adjacent to the border-fault system. The most famous intrusion is the Palisades . At its northern termination, the Palisades intrusion becomes -like and feeds one of the lava flows (Ratcliffe, 1988). The Newark basin also contains three extrusive formations (Orange Mountain Basalt, Preakness Basalt, Hook Mountain Basalt), each consisting of multiple flow units (Fig. 14a). Although each basalt formation has a distinct , all extrusive (and intrusive) rocks are -normative tholeiites (Fig. 14c). Cyclical lacustrine strata with Milankovitch periodicities preceding, interbedded with, and succeeding the extrusive formations indicate that extrusive activity occurred in less than 600,000 (Olsen et al., 1996b, 2003). This duration likely applies to other Mesozoic rift basins in eastern North America because these basins contain basalts with the same geochemistry as those in the Newark basin (Fig. 14c). As noted in the introduction, radiometric dates indicate that all igneous activity (intrusive and extrusive) occurred at ~200 Ma (see Olsen et al., 2011, and references therein).

Latest Triassic/earliest Jurassic igneous activity occurred throughout eastern North America. Diabase dikes are present from the southeastern United States to maritime Canada (Fig. 4a) (e.g., May, 1971; McHone, 2000). Most dikes in the southeastern U.S. strike NW-SE and N-S, and cut across the rift basins. In the northeastern U.S. and maritime Canada, the dikes generally strike NE-SW, and were intruded while lava flows accumulated in the actively subsiding rift basins (e.g., Schlische et al., 2003). These intrusive and extrusive rocks in eastern North America are

page 12 part of a vast igneous province (>10,000,000 km2; Marzolli et al., 1999; McHone, 2000, 2003), known as the Central Atlantic Magmatic Province (CAMP), that also covers parts of South America, Africa, and Europe (Fig. 4b).

Seaward-dipping reflections (SDRs) are present at the continent-ocean boundary of eastern North America from the southeastern U.S. to southeastern Nova Scotia, Canada. They are, however, absent for the remainder of maritime Canada. The SDRs likely represent a volcanic and/or volcanoclastic wedge at the continent-ocean boundary (and account for the East Coast Magnetic Anomaly) (Fig. 1). It is unclear whether the SDRs are associated with CAMP or a second pulse of igneous activity (for a full discussion, see Schlische et al., 2003). Although the southeastern part of the ENAM continental margin is magma-rich (i.e., SDRs are present) and the northwestern part is magma-poor (i.e., SDRs are absent), CAMP-related igneous rocks are present along the entire ENAM continental margin. For example, the northwestern Scotian and Newfoundland segments of the ENAM margin lack SDRs, but the Fundy, Orpheus, and Jeanne d’Arc rift basins all contain CAMP-related intrusive sheets and/or basalt flows (e.g., Olsen, 1997; Withjack and Schlische, 2005; Withjack et al., 2012a).

Road log to Stop 4. Travel time: ~10 minutes Go… Total 18. Exit the park and turn left onto Ringing Rocks Road 0.5 mi 0.5 mi 19. Turn left onto Bridgeton Hill Road 1.5 mi 2.0 mi 20. Turn right onto PA-32 / River Road. 0.2 mi 2.2 mi 21. Turn left onto River Road and take bridge over Delaware River to 0.2 mi 2.4 mi Milford, NJ 23. Turn left onto Church Street <0.1 mi 2.5 mi 24. Turn left to stay on Church Street <0.1 mi 2.5 mi 25. Take first right onto Spring Garden Street which becomes / County ~1.8 mi 4.3 mi Road 627. After ~1.25 miles, you will pass the junction with Spring Garden Road. After this, look for railroad mile marker 37, and park in the large pull-out on the right. Proceed to the main outcrop by walking west along the unused railroad tracks.

STOP 4: Perkasie Member of Passaic Formation at Pebble Bluff near Milford, NJ

These outcrops consist of thick sequences of red and sandstone alternating with cyclical black, gray, and red mudstone and sandstone of the Perkasie Member of the Passaic Formation (Fig. 15a). Depositional environments ranged from deep perennial lakes (black ) to debris-flow deposits of alluvial fans (red poorly sorted conglomerate) (Olsen et al., 1989). The sequence of strata above the 12-m-mark in Figure 15a represents the progressive flooding of the distal toes of an during rising lake levels, followed by lake highstand and regression.

Individual lake-level (Milankovitch) cycles (see Fig. 16a) of the Perkasie Member in this area average 7 m thick, as compared with a mean of 4.4 m at New Brunswick, NJ, and Pottstown, PA, and 5.3 m in the Titusville core (Fig. 15b; Olsen et al., 1996a). These thickness trends (Fig. 16b)

page 13 show that subsidence rates increased from the hinged margin of the basin toward the border-fault zone as well as from the lateral edges toward the center of the basin (Schlische, 1992).

Road log to Morristown Hyatt. Travel time: ~1 hour, 3 minutes Go… Total 26. Head west on County Road 627. 1.1 mi 1.1 mi 27. Turn right onto Crabapple Hill Road 1.0 mi 2.1 mi 28. Turn right onto Church Road 2.4 mi 4.5 mi 29. Turn right onto Milford Warren Glen Road / County Road 519 <0.1 mi 4.5 mi 30. Turn left onto Spring Mills Road / County Road 614 2.5 mi 7.0 mi 31. Continue onto Little York Mt. Pleasant Road / Route 631 / Route 614 0.2 mi 7.2 mi 32. Turn right onto Little York Pattenburg Road / County Road 614 4.9 mi 12.1 mi 33. Turn right onto Baptist Church Road (following signs for I-78) 0.1 mi 12.2 mi 34. Turn left to merge onto I-78 East 18.2 mi 30.4 mi 35. Take Exit 29 for I-287 toward US-202 / 206 / I-80 / Morristown / 0.6 mi 32.0 mi Somerville 36. Keep left at the fork and merge onto I-287 North. We will pass outcrops 15.8 mi 46.8 mi of Preakness Basalt containing . 37. Take exit 36B for County Rt 510 / Lafayette Avenue 0.2 mi 47.0 mi 38. Merge onto County Rt 510 / Lafayette Avenue 0.5 mi 47.5 mi 39. Turn right onto Morris Street 0.2 mi 47.7 mi 40. Take the 2nd right onto E Park Place <0.1 mi 47.8 mi 41. Continue straight onto Speedwell Avenue. Hotel is on right. 0.2 mi 47.9 mi

References

Cornet, B., Olsen, P.E. 1985. A summary of the biostratigraphy of the of eastern North America, with comments on early Mesozoic provinciality. In: Weber, R., ed., III Congresso Latinoamericano de Paleontologia. Mexico., Simposio Sobre Floras del Triasico Tardio, su Fitografia y Paleoecologia, Memoria, p. 67-81. Faill, R.T. 1973. Tectonic development of the Triassic Newark-Gettysburg basin in . Geological Society of America Bulletin, 84, 725-740. Faill, R.T. 1988. Mesozoic tectonics of the Newark basin, as viewed from the Delaware River. In: Husch, J.M., Hozik, M.J. (eds) Geology of the Central Newark Basin, Field Guide and Proceedings. Fifth Meeting of the Geological Association of New Jersey, Rider College, Lawrenceville, 19-41. Gawthorpe, R.L., Leeder, M.R. 2000. Tectono-sedimentary evolution of active extensional basins. Basin Research, 12, 195-218. Hames, W.E., McHone, J.G., Renne, P.R., Ruppel, C. (eds) 2003. The Central Atlantic Magmatic Province, Insights from Fragments of Pangea. American Geophysical Union, Geophysical Monograph 136, 267 p. Hull, J. 1988. Thickness-displacement relationships for deformation zones. Journal of Structural Geology, 10, 431- 435. Kent, D.V., Olsen, P.E. 1999. Astronomically tuned geomagnetic polarity time scale for the Late Triassic. Journal of Geophysical Research, 104, 12,831-12,841. Kent, D.V., Olsen, P.E., Witte, W.K. 1995. Late Triassic-Early Jurassic geomagnetic polarity and paleolatitudes from drill cores in the Newark rift basin (Eastern North America). Journal of Geophysical Research, 100 (B8), 14,965-14,998. Knott, S.D. 1994. Fault zone thickness versus displacement in the Permo-Triassic of NW England. Journal of the Geological Society, London, 151, 17-25. Knott, S.D., Beach, A., Brockbank, P.J., Brown, J.L., McCallum, J.E., Welbon, A.I. 1996. Spatial and mechanical

page 14 controls on normal fault populations. Journal of Structural Geology, 18, 359-372. Lyttle, P.T., Epstein, J.B. 1987. Geologic map of the Newark 1°x2° quadrangle, New Jersey, Pennsylvania and . U.S. Geological Survey, Miscellaneous Investigations Series Map I-1715, 1:250,000. Malinconico, M.L. 2010. Synrift to early postrift basin-scale groundwater history of the Newark basin based on surface and borehole vitrinite reflectance data. In: Herman, G.C., Serfes, M.E. (eds) Contributions to the Geology and Hydrogeology of the Newark Basin. New Jersey Geological Survey Bulletin 77, C1-C38. Manspeizer, W., Cousminer, H.L. 1988. Late Triassic-Early Jurassic synrift basins of the U.S. Atlantic margin. In: Sheridan, R.E., Grow, J.A. (eds) The Atlantic continental margin—U.S. Geological Society of America, The Geology of North America, I-2, 197-216. Marzolli, A., Renne, P.R., Piccirillo, E.M., Ernesto, M., Bellieni, G., deMin, A. 1999. Extensive 200-million-- old continental flood basalts of the Central Atlantic Magmatic Province. Science, 284, 616-618. May, P.R. 1971. Pattern of Triassic-Jurassic diabase dikes around the North Atlantic in the context of the predrift configuration of the continents. Geological Society of America Bulletin, 82, 1285-1292. McHone, J.G. 1996. Broad-terrane Jurassic flood basalts across northeastern North America. Geology, 24, 319-322. McHone, J.G. 2000. Non-plume magmatism and rifting during the opening of the central Atlantic Ocean. Tectonophysics, 316, 287-296. McHone, J.G. 2003.Volatile emissions from Central Atlantic Magmatic Province basalts: Mass assumptions and environmental consequences. In: Hames, W.E., McHone, J.G., Renne, P.R., Ruppel, C. (eds) The Central Atlantic Magmatic Province, Insights from Fragments of Pangea. American Geophysical Union, Geophysical Monograph 136, p. 241-254. McLaughlin, D.B. 1948. Continuity of strata in the Newark series. Papers of the Michigan Academy of Science, Arts and Letters, 32, 295-303. Olsen, P.E. 1986. A 40-million-year lake record of early Mesozoic climatic forcing. Science, 234, 842-848. Olsen, P.E. 1988. Continuity of strata in the Newark and Hartford basins of the Newark Supergroup. In: Froelich, A.J., Robinson, G.R., Jr. (eds) Studies of the Early Mesozoic Basins in the Eastern United States. U.S. Geological Survey Bulletin, 1776, 6-18. Olsen, P.E. 1997. Stratigraphic record of the early Mesozoic breakup of Pangea in the -Gondwana rift system. Annual Reviews of Earth and Planetary Science, 25, 337-401. Olsen, P.E., Whiteside, J.H. 2008. Pre-Quaternary Milankovitch cycles and climate variability. In: Gornitz, V. (ed.), Encyclopedia of Paleoclimatology and Ancient Environments, Earth Science Series, Kluwer Academic Publishers, Dordrecht, the Netherlands, 826-835 (ISBN: 978-1-4020-4551-6). Olsen, P.E., Kent, D.V. 1996. Milankovitch climate forcing in the tropics of during the Late Triassic: Palaeogeography, Palaeoclimatology, Palaeoecology, 122, 1-26. Olsen, P.E., Kent, D.V., Whiteside, J. H. 2011. Implications of the Newark Supergroup-based astrochronology and geomagnetic polarity time scale (Newark-APTS) for the tempo and mode of the early diversification of the Dinosauria. Earth and Environmental Science Transactions of the Royal Society of Edinburgh, 101, 201–229. Olsen, P.E., Kent, D.V., Cornet, B., Witte, W.K., Schlische, R.W. 1996a. High-resolution stratigraphy of the Newark rift basin (early Mesozoic, eastern North America). Geological Society of America Bulletin, 108, 40- 77. Olsen, P.E., Kent, D.V., Et-Touhami, M., Puffer, J. 2003. Cyclo-, magneto-, and bio-stratigraphic constraints on the duration of the CAMP event and its relationship to the Triassic-Jurassic boundary. In: Hames, W.E., McHone, J.G., Renne, P.R. Ruppel, C. (eds) The Central Atlantic Magmatic Province, Insights from Fragments of Pangea. American Geophysical Union, Geophysical Monograph 136, 7-32. Olsen, P.E., Schlische, R.W., Fedosh, M.S. 1996b. 580 kyr duration of the Early Jurassic flood basalt event in eastern North America estimated using Milankovitch cyclostratigraphy. In: Morales, M., ed., The Continental Jurassic: Museum of Northern Arizona Bulletin 60, 11-22. Olsen, P.E., Schlische, R.W., Gore, P.J.W. (eds). 1989. Tectonic, depositional, and paleoecological history of early Mesozoic rift basins, eastern North America. International Geological Congress Field Trip T-351, American Geophysical Union, 174 p. Ratcliffe, N.M. 1988. Reinterpretation of the relationships of the western extension of the to the lava flows at Ladentown, New York, based on new core data. In Froelich, A.J., Robinson, G.R., Jr. (eds) Studies of the Early Mesozoic Basins of the Eastern United States. U.S. Geological Survey Bulletin 1776, 113-135. Ratcliffe, N.M., Burton, W.C., D’Angelo, R.M., Costain, J.K. 1986. Low-angle extensional faulting, reactivated mylonites, and seismic reflection geometry of the Newark basin margin in eastern Pennsylvania. Geology, 14, 766-770. Sanders, J.E. 1963. Late Triassic tectonic history of northeastern United States. American Journal of Science, 261,

page 15 501-524. Schettino, A., Turco, E. 2009. Tectonic history of the western Tethys since the Late Triassic. Geological Society of America Bulletin, 123, 89-105. DOI: 10.1130/B30064.1 Schlische, R.W. 1992. Structural and stratigraphic development of the Newark extensional basin, eastern North America; Implications for the growth of the basin and its bounding structures. Geological Society of America Bulletin, 104, 1246-1263. Schlische, R.W. 1993. Anatomy and evolution of the Triassic-Jurassic continental rift system, eastern North America. Tectonics, 12, 1026-1042. Schlische, R.W. 1995. Geometry and origin of fault-related folds in extensional settings. AAPG Bulletin, 79, 1661- 1678. Schlische, R.W. 2003. Progress in understanding the structural geology, basin evolution, and tectonic history of the eastern North American rift system. In: LeTourneau, P.M., Olsen, P.E. (eds) The Great Rift Valleys of Pangea in Eastern North America, Volume 1, Tectonics, Structure, and Volcanism. Columbia University Press, New York, 21-64. Schlische, R.W., Withjack, M.O. 2005a. The early Mesozoic Birdsboro central Atlantic margin basin in the Mid- Atlantic region, eastern United States: Discussion. Geological Society of America Bulletin, 117, 823-828. Schlische, R.W., Withjack, M.O., 2005b. Normal faults in the Passaic Formation at , in Gates, A.E., ed., Newark Basin—View from the 21st Century: 22nd Annual Meeting of the Geological Association of New Jersey, Field Guide and Proceedings, p. 120-124. Schlische, R.W., Withjack, M.O., Eisenstadt, G. 2002. An experimental study of the secondary deformation produced by oblique-slip normal faulting. AAPG Bulletin, 86, 885-906. Schlische, R.W., Withjack, M.O., Olsen, P.E. 2003. Relative timing of CAMP, rifting, continental breakup, and inversion: tectonic significance. In: Hames, W.E., McHone, J.G., Renne, P.R. Ruppel, C. (eds) The Central Atlantic Magmatic Province, Insights from Fragments of Pangea. American Geophysical Union, Geophysical Monograph 136, 33-59. Steckler, M.S., Omar, G.I., Karner, G.D., Kohn, B.P. 1993. Pattern of hydrothermal circulation with the Newark basin from fission-track analysis. Geology, 21, 735-738. Wheeler, G. 1939. Triassic fault-line deflections and associated warping. Journal of Geology, 47, 337-370. Whiteside, J.H., Olsen, P.E., Kent, D.V., Fowell, S.J., Et-Touhami, M. 2007. Synchrony between the CAMP and the Triassic-Jurassic mass-extinction event? Palaeogeography, Palaeoclimatology, and Palaeoecology, 244, 345- 367. Whiteside, J.H., Olsen, P.E., Kent, D.V., Fowell, S.J., Et-Touhami, M. 2008. Synchrony between the Central Atlantic magmatic province and the Triassic–Jurassic mass-extinction event? Reply to comment of Marzoli et al. Palaeogeography, Palaeoclimatology, Palaeoecology, 262(3-4), 194-198 Withjack, M.O., Olsen, P.E. 1999. Rift Basins and Passive Margins Tectonics Seminar, Mobil Technology Company, July 14-24, 1999. Withjack, M.O., Schlische, R.W. 2005. A review of tectonic events on the passive margin of eastern North America. In: Post, P. (ed) Petroleum Systems of Divergent Continental Margin Basins. 25th Bob S. Perkins Research Conference, Gulf Coast Section of SEPM, 203-235. Withjack, M.O., Schlische, R.W., Olsen, P.E. 1998. Diachronous rifting, drifting, and inversion on the passive margin of central eastern North America: An analog for other passive margins. AAPG Bulletin, 82, 817-835. Withjack, M.O., Baum, M.S., Schlische, R.W. 2010. Influence of preexisting fault fabric on inversion-related deformation: A case study of the inverted Fundy rift basin, southeastern Canada. Tectonics, 29, TC6004, 22 pages, doi:10.1029/2010TC002744. Withjack, M.O. Schlische, R.W., Olsen, P.E. 2012a. Development of the passive margin of eastern North America: Mesozoic rifting, igneous activity, and inversion. In: Roberts, D., and Bally, A., eds.: Regional Geology and Tectonics: Phanerozoic Rift Systems and Sedimentary Basins, Elsevier, p. 301-335. Withjack, M.O., Schlische, R.W., Malinconico, M.L., Olsen, P.E. 2012b. Rift-basin development—lessons from the Triassic-Jurassic Newark basin of eastern North America. In: Post, P.J., Brown, D.E., Tari, G.C. (eds) Conjugate Divergent Margins, Geological Society (London) Special Publication, in press.

page 16 Fig. 7a. Shaded-relief map of Newark basin and surrounding areas. Red NJH box shows area detailed in (b). CP, Coastal Plain; DR, Delaware River; RF DWG, Delaware Water Gap; NB, Newark basin; NJH, New Jersey High- PS DWG lands; NYC, ; PS, Palisades sill; RF, Ramapo border fault; VR, VR Valley & Ridge; WM, (lava flows). Assembled from 1/3

WM NYC arc-second NED CONUS digital elevation model available from http://nmviewogc.cr.usgs.gov/viewer.htm.

NB DR

H N CP 5.2 miles

1 Fig. 7b. Shaded-relief map showing location 4 of field-trip stops (stars) and Morristown 3 Hyatt (circled H). 2

Fig. 7c. Parts of the U.S.G.S. Allentown N and Reading 15" topographic maps showing field-trip stops (stars). 5.2 miles

1 4

3

2

page 17 Lithologic Legend

Jurassic diabase mostly mostly conglom- red gray erate

Jurassic-Triassic Brunswick Group (Passaic Formation)

Triassic Lockatong Fm. T Rs Triassic Stockton Fm.

1 Jacksonburg Fm.

Ordovician Eppler Fm. 4

Ordovician-Cambrian 2 Allentown 3

Cambrian Leithsville Fm

Cambrian Hardyston Fm

Ym b

Y hp Y h Ym g g Proterozoic crystalline rocks

N 3 ~ 3 km

T Rs Fig. 8. Geologic map of part of the Newark 1°x2° quadrangle, showing the northwestern Newark basin and adjacent prerift strata and basement in the vicinity of the Delaware River. Stars give field-stop locations. Map is from Lyttle & Epstein (1987). Note that the geology of the Lockatong and Passaic formations differs slightly from other versions in this guidebook, which reflect updated mapping utilizing the results of the Newark Basin Coring Project.

page 18 Stop 1: Rt. 611 near Rt. 212, Durham Furnace, PA (N40°34.850' / W75°11.818')

1.1. Age of stratigraphic unit: Cambrian

1.2. Distance from basin- bounding fault: 1-2.5 km (FW)

1.3. Description of sedi- mentary features: Carbonate sedimentary rocks with mudcracks; shallow marine conditions a

1.4. Description of struc- tural features and tec- tonic environment: Anticlines and synclines with steeply dipping and overturned limbs; cleavage is widely spaced and converging downward in massive competent unit; closely spaced and diverging downward in less compe- tent units; related to b shortening produced during Appalachian orogenies

Fig. 9. a. Photo of outcrop-scale fold in the Cambrian Leithsville Formation at Stop 1. Photo by Roy Schlische. b. Interpretation of photo in (a); bedding is red; cleavage is yel- low. c. Close-up photo of anticline with inter- preted bedding and cleavage. Photo by James Grieshaber.

c page 19 Bounding fault of Newark rift basin: Rt. 611 & Lehnenberg Rd., Monroe, PA (N40°34.245' / W75°11.481')

1.5. Age of stratigraphic units: Late Triassic 1.6. Distance from border fault: <0.1 km (HW) 1.7. Apparent dip angle & direction of bedding: 15-20°N 1.8. Description of sedimentary features & depositional environments: Cyclical black, gray, and red clastic sedimentary rocks; fine to very coarse grained (conglomerates); deep- and shallow-water lakes; alluvial fans 1.9. Description of structural features & tectonic environment: Border fault of Newark basin; fault dips gently about 25-30° to the SE and parallels Paleozoic thrust fault zone; structures related to rifting and extension

a

SE NW b U.S.G.S. Core Holes Trpg Trp 400 0 ft

Proterozoic Y 200 ft Trpl

Passaic Formation 0 ft (Sea 27° ate on level) rb ca an ici ov -200 ft rd 34° -O ro Fig. 10. Aspects of the border-fault region at mb Ca Trp - Red mudstone and sandstone Monroe, PA. a. Outcrop photo by James Passaic -400 ft Trpg - Green & black shale & sandstone Grieshaber. b. Exposed section showing cycli- Formation Trpl - Limestone-clast conglomerate cal black, gray, and red clastic sedimentary 0 200 400 600 400 ft rocks. c. Geologic cross section based on core data (after Ratcliffe et al., 1986). c 0 60 120 180 240 m

page 20 Stop 2: Rt. 611 & Trauger Crossing Rd., Kintnersville, PA (N40°32.610' / W75°10.962')

2.1. Age of stratigraphic units: Late Triassic (Passaic Formation, Member K) 1 2.2. Distance from border fault: 3-4 km (HW) 2.3. Apparent dip angle & direction of bedding: ~5-10° N 2.4. Description of sedimentary features & depositional environments: Red, mostly massive mudstone with evaporites; very shallow-water lake deposits 2.5. Description of structural features & tectonic environment: 2 NNE-striking, SE-dipping normal faults produced by extension; multiple sets with plumose markings

N S Fault 2 Fault 3 Fault 4 Fault 1 3

a ~1 meter c

106 Data from Hull (1988), Knott (1994), and Knott et al. (1996). This outcrop 105

104

103 ) 2 m 10 ( t n

e 101 m e

c 0 a 10 l p s i

D 10-1 b 10-2 10-3 d 10-4 10-5 10-4 10-3 10-2 10-1 100 101 102 103 Fault-zone thickness (m)

Fig. 11. a. Sketch of outcrop cut by multiple normal faults with variable displacements. b. Photo of fault 1 by Roy Schlische; Alissa Henza and Martha Withjack for scale. c. Hypothesized evolution of normal faults in cross section, showing the linkage of originally isolated segments and widening of the fault zone. d. Log-log plot of fault displacement versus fault-zone thickness (breccia and gouge) for faults 2, 3, 1, and 4; the data are comparable to other measurements for faults cutting sedimentary rocks. Modified from Schlische & Withjack (2005b).

page 21 Topographic Extension 3 contour line direction Fig. 12a. Inferred 1 Contour line for closed depression 3 F topography and flu- F F 3 Stream 4 vial inputs for a rift Approx. fault trace basin crudely similar 4 5 F to the Newark basin. 6 5 A Most of the footwall F 6 slopes away from the 7 7 8 9 8 basin; most of the 6 4 RR E hanging wall slopes 3 2 2 5 toward the basin. 1 Consequently, direct 3 sediment input from the footwall is limited (except at relay ramps between over- Lake lapping fault H segments). This may account, in part, for the relatively fine- 4 grained strata adja- cent to the border- H 1 A=axial stream N 3 H E=escarpment stream fault system. Modi- H H=hanging-wall stream fied from Schlische & H F=footwall stream Extension RR=relay ramp stream Withjack (2005a). direction

Fig. 12b. Schematic cross sections Eventual erosion level showing border-fault development during deposition. (i) Model with multiple active faults. Coarse-grained sediments preferentially accumulate in hanging walls of outer border fault. Later erosion removed these sedimen- Multiple active faults i

tary rocks. (ii) Model with basinward Coarse clastics migration of border faults. During the early stages of rifting, the outer bor- der fault was active, and coarse- grained sediments accumulated in its hanging wall. During the later stages Very coarse clastics Future fault of rifting, the inner border fault became active, and coarse-grained Active fault sediments accumulated in its hanging wall. Later erosion removed the ii coarse-grained sedimentary rocks. Thus, the present-day edge of the Eventual erosion level basin has shifted basinward from its position during deposition of the Passaic Formation. Modified from Schlische & Withjack (2005b). Inactive fault Active fault

Fig. 12c. Estimated amount of post-rift ero- sion for transect along seismic line NB-1. Red NW SE bars show eroded syn-rift section predicted by vitrinite-reflectance analysis; grey area shows potential error (± 30%). The magnitude of ero- sion varies from 4 to 6 km. Vitrinite-reflectance 5 km data are from Malinconico (2010); figure is modified from Withjack et al. (2012b).

page 22 Stop 3: Ringing Rocks County Park, Upper Black Eddy, PA (N40°33.639' / W75°07.735') 3.1. Distance from border fault: 3-5 km (HW)

Part A: Boulder field; boulders composed of Coffman Hill diabase 3.2. Origin and likely age of source of boulders: Intrusive sheet of diabase of latest Triassic / Early Jurassic age (~201 Ma) (Coffman Hill diabase) 3.3. 3D geometry of diabase body: Folded sheet; sedimentary layers surrounding intrusion define a doubly plunging syncline.

Part B: Waterfall 3.4. Type of rock(s) present: Thermally metamorphosed rocks of Passaic Formation below dia- base sheet; gray color regardless of composition; ripple marks and mudcracks are original sedimentary structures. 3.5. of fractures: Common strikes are 270° and 350°. The dip angle is steep (70- 90°). The fractures are joints because there is no obvious shear offset across the fractures. Fractures in hornfels in Newark basin tend to be more closely spaced than in unmetamorphosed strata. a

b

Fig. 13. Ringing Rocks County Park. a. Photo of waterfall; strata have undergone contact metamorphism from the overlying diabase sheet. b. Photo of boulder field; boulders con- sist of weathered diabase.Photos by James Grieshaber.

page 23 HFTQ basalt Scaled and Filtered ACE & NBCP Core Joined Depth Ranks Precession Index Kyr LTQ basalt Depth Ranks Depth Ranks (25.0-16.7 kyr) (154-1635 kyr BP) 1600 Meters HFQ basalt 1400

HTQ basalt 1300 1400

Massive basalt 1200

Red vesicular up | Gray Hook Mt. vesicular up basalt 1100 Basalt 1200

Columnar basalt 1000 r

Prismatic fractured s y e 1000 r basalt 900 k o 0 C 8

Coarse-grained “sills” E 5

C 800 A Pillow basalts 800 700 Thin discontinuous flows 600 Preakness Basalt 600 500 Red clastic rocks

Black / gray / light gray clastic rocks 400 400 Purple / light purple / pink clastic rocks 300 e

Green clastic or l l Orange Mt. calcareous rocks i 200 v Basalt

s 200 n

White limestone or i t dolomite r 100 a

Tan sandstone M 0 0 g Fig. 14a. Stratigraphy of extrusive interval in the northern Newark g r u r u a d l e r basin based on the Martinsville and Army Corps of Engineers (ACE) d b k r e p e r i s y o f e p a f cores. Cyclostratigraphy of lake deposits in sedimentary strata con- y r d t t p t l w r e m n

strains the duration of the extrusive interval to approximately e u e a e o u C G N P H D 600,000 years. Modified from Olsen et al. (1996b) and Whiteside et F al. (2007). r y k 0 0 1 ± 0 8 5

HTQ HFQ HFQ+LTQ HFTQ Fig. 14c. Correlation and geochemistry of extrusive rocks in various Triassic-Jurassic rift basins in eastern North America. Abbreviations for basalt geochemistry are: HTQ = high-titanium quartz-normative; HFQ = high- quartz-normative; LTQ = low-titanium quartz-normative; Fig. 14b. Contact between Orange Mountain Basalt and underlying Passaic HFTQ = high-iron & titanium quartz-normative basalt. Fm. in in West Paterson, NJ. Photo by Roy Schlische. Modified from Schlische et al. (2003) based on Olsen (1997).

page 24 Fig. 15a. Strata at Pebble Bluff. LEFT: Measured section of lacustrine deposits interbedded with alluvial-fan deposits. Modified from Olsen et al. (1989). RIGHT: Photo of con- glomerate by Martha Withjack.

Gray well-sorted sandstone with tilted surfaces (shoreline)

Black and gray laminated claystone and siltstone (deep lake)

Gray well-sorted sandstone and gravel (shoreline)

Red well-sorted sandstone with carbonate nodules (fluvial with wave reworking and formation)

Red well-sorted conglomerate

Red poorly sorted conglomerate (debris flow)

Stop 4 (Optional): Pebble Bluff, near Milford, NJ 4.1. Age of stratigraphic units: Late Triassic (Passaic Formation, Perkasie Member) 4.2. Distance from border fault: ~2 km (HW) 4.3. Description of sedimentary features & depositional environments: Mudstone, sandstone, and conglomerates

7 6 Black feet meters 5 100 30 N Gray

Purple 25 km 1 2 Ottsville, Red 8 Pa (4) 4 3 Milford, NJ (5) PA NJ 0 0 Rutgers New no. 1 (2) Brunswick, NJ (1) Titusville ) O Holland no. 2 (3) - N (

Tylersport, Twp., NJ (6) r e Sanatoga, p b o Pa (7) r m c

Pa (8) t e u o M e i s a k r e P e r o c 2 . M - o L n r e l e l i b v s m u e t i T m s g c m

m=mud m s g c m s g c m s g c s=sand m s g c m s g c g=gravel c=cobble

m s g c m s g c Fig. 15b. Measured sections of the Perkasie Member of the Passaic Formation from across the Newark basin. The sections generally thicken and coarsen toward the border-fault system and thin toward the lateral edges of the basin. Modified from Olsen et al. (1996a).

page 25 Depth Rank Depth Rank Depth Rank 0 5 0 5 0 5 0

1 ) e l e l c c e y l e y l c c c c y y y t c d ) i c n e c l n i ) u y r c o t t i e i o r y l n s c p y c c 2 i s e r k y t m n c e c n 0 o c c e t e c d 2 e e u r c n r n o p c i u y l e r H o h 0 y r p g n 0 y 0 3 u a m 0 , 0 0 a o V 0 ( 0 0 L c , ( r 0 r c 0 0 , y y 4 k M 2 0 k ~ ( 0 ~ 0 0 1 2 0 ~ 4 1

5

Black microlaminated claystone Gray mud-cracked mudstone Gray laminated siltstone Red massive mudstone Fig. 16a. Hierarchy of Milankovitch lake-level cycles in the Passaic Formation. Depth rank uses color and sediment fabrics (left) to estimate relative water depth. Modified from Olsen et al. (1996a) and Olsen and Kent (1996).

NW SE TThhicickkeeninggTTrerenndsds Byram Nursery Core NBCP Cores M=Martinsville N=Nursery P=Princeton R=Rutgers S=Somerset T=Titusville W=Weston

Tohickon 15.0% Member 9.8% 11.9%

Byram 20.0% Skunk Hollow Member

5.5% 22.2%

VE = 100/1 m 0 3 Fig. 16b. Percent-change in thickness between correlative units of adjacent NBCP 3 km cores. Units generally thicken toward the center of the basin and toward the border- m s g c fault system. Modified from Schlische (2003) based on data in Olsen et al. (1996a). Black 0.1° m=mud Gray s=sand 0.5° Sedimentary rocks Fig. 16c. Core-to-outcrop correlation of the two members of the Lockatong For- g=gravel Purple c=cobble 1° mation. The units thicken subtly toward the border fault. A slope of <0.5° accounts 2° Red 5° for the differential thickening. Modified from Withjack et al. (2012b) based on Olsen et al. (1996a).

page 26

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