Teaching Structural Geology, Geophysics, and Tectonics in the 21St Century Workshop: Blue Ridge Foothills Field Trip
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Teaching Structural Geology, Geophysics, and Tectonics in the 21st Century Workshop *T]M:QLOM.WW\PQTT[.QMTL<ZQX July 15, 2012 36˚ 36˚ 8ZWN*WJ0I\KPMZ N FBR Cc 40 Chlorite isograd Pz English Tectonics and Structural Geology Research corresponds to PR GSF Mtn the Miller Cove fault Cs Cw University of Tennessee–Knoxville &V 83˚30' Stone Cc 7<2 6 6, ) Mtn Zsb 5 7 MCF ( ( Cc 9 Chilhowee Shields 1 GCF Fair Garden , anticline Cw C 1 GSF Mtn 1 Mountain Cw ( 8 6 Cs 6 =G Zd ( ( e 0&) + n ( li PF :HEE 7 c yn =G DCF 0WQ e s / ov =UE C ller Mi Zsb PC Wilhite Slate *%) 1 : &Z &Z Wear GBF =VE 2 =G Cove G 3 3] Cc *6)=G Zwe Zch 4 8 5 7 Zam GF Western Blue Ridge Geology Pz Tuckaleechee Cove 6 GF Southwestern North Carolina & Pz 84˚ *6) 441 Southeastern Tennessee Zch Zwe Map compiled by Zsb GSMNP GBF Cw Cades =FK OF GBF Pz Cove Zwe Mark W. Carter 1995–1996 RCF Zd Zch (QJLQHHULQJ Modified by J. Ryan Thigpen, 2003 G/OF 10 Zch Mineralogy and Bob Hatcher, 2003, 2012 9 nal Structu gio ra 11 Zam Metamorphic e l GSF R Geology Zch and Igneous Cs MCF Pz Petrology Geochemistry Cwh Geochronology 35˚30' 35˚30' Economic Geophysics Tectonics Geohydrology Geology f. C o k e D , e o r s l r <E s Research i c y M n 5 c i a C n i s I e M t n c a R r t <E e y U i i i e M l m n F a t H a Zd c / u y Cc L Zwe n N a U t g i t i u h o y r b l e c c r l t E u a s n s s Q c r , e u o a i Zch i m n r A i b H Ch T M n L t a i t I n H GBF l h c S n m U i M i , n s e s l A a t r a e * t a S m e r a , Chlorite isograd R l c c t ic c h e Ten Zgb i o h S s i C n <E e d e a n Zam n y n y corresponds to s d n h a Cs s HF c a ic ee r e P g R. m s r o i the Miller Cove c O f s Greenbrier 129 s fault Zwe n Sedimentation fault e HydrocarbonExploration v Paleontology e Stratigraphy Zwe Zd in a Cc l Geomorphology Cwh Zch tic R an Science Alliance n IDXOW w Zch <E Center of Excellence 84˚30' TP o Zd kt uc Zam 0 5 10 15 20 Zwe D \ N Zd NC Zwe Map compiled (and modified) from: R e =ZH kilometers M. P. Ausburn et al. (1998) Topton quad., NC Geol Survey in Zwe King et al. USGS Professional Paper 349 P Cc cl D. W. Mohr (1975) Noland Creek quad., NC Geol Survey 6 I TN Cs yn Zd Univ. of South Carolina unpublished Ph. D. dissertation . s Tellico River EXPLANATION J. O. Costello (1993) f n Univ. of Tennessee unpublished M.S. theses: o OCbam rs Cnt M. W. Carter (1994) OO e e WEST EAST D. J. Geddes (1995) L v p S. L. Martin (1997) 0 o (Murphy-Alum Cave syncline) C p Paleozoic Valley H. E. Phillips (1952) E Zwe t Pz and Ridge rocks in R. I. Rackley (1951) OCbam l u Cs fa Blue Ridge windows L. S. Wiener, unpublished map Omb Mineral Bluff Group W Zam L. S. Wiener and C. E. Merschat (1992) SW NC, Cwh Cc SE TN, & N GA Geologic Map, NC Geol Survey D Chilhowee Group UNCONFORMITY UH lt 83˚30' Shady Dolomite u OCbam * s fa Zd Rome Formation Brasstown Fm., Andrews Fm. ie H Murphy Marble g iw Omb Zch Cw Cs Sandsuck Fm. g a Cnt Zd ssee R. Zam Walden Creek Gr. Nantahala–Tusquittte Fm. a r e N Cwh Wilhite Slate Murphy Gr. le ne n (undivided) M l a UNCONFORMITY? Cc i to r UNCONFORMITY? s r Cc M e te Zd t Cnt Dean Fm. Zd Dean Fm. Zd i ye h Zam a Ammons Fm. Zam OCbam ch Ammons Fm. Zwe W e Zwe O Zam g Wehutty Fm. Zwe Wehutty Fm. c M o o Zch Zch e o Great Smoky Gr. Copperhill Fm. Zch e l t Great Smoky Gr. Copperhill Fm. il r e a s v C Zrb R Zwe ye Rich Butt Ss. Cwh . a Cwh H Zsb Pigeon Siltstone / Metcalf Phyllite D Omb Roaring Fork Ss. Longarm Qzt. Zam RDH '03, '12 Field trip stop Wading Branch Fm. Unrug "fossil" locality & 35˚ 35˚ Snowbird Gr. 3 July 15 Blue Ridge Foothills trip Repetski 7/03 sample(s) UNCONFORMITY 84˚30' Zd 84˚ Zwe Additional Repetski 7/03 sample(s) Zch Yb Grenvillian basement RDH 7/1/2012 GA Repetski conodont(s) Additional explanation inside front cover. Faults Towns Tennessee North Carolina GBF—Greenbrier D—Ducktown M—Murphy G/OF—Greenbrier/Oconaluftee TP—Tellico Plains Ch—Cherokee OF—Oconaluftee W—Walland MCF—Miller Cove G—Gatlinburg GF—Gatlinburg PF—Pigeon Forge DCF—Dunn Creek S—Sevierville GCF—Guess Creek S—Sevierville GSF—Great Smoky PC—Pittman Center RCF—Rabbit Creek L—Laurel WF—Whitestone C—Cosby HF—Hayesville N—Newport Blue Ridge Foothills Field Trip PREAMBLE 7KLV¿HOGWULSJXLGHLVRQHWKDW,KDYHXVHGIRUXQGHUJUDGXDWHVWUXFWXUDOJHRORJ\JUDGXDWHVWUXFWXUDO JHRORJ\$SSDODFKLDQVWUXFWXUHDQGJUDGXDWHWHFWRQLFV¿HOGWULSVDVZHOODVVOLJKWO\LQPRGL¿HGIRUPIRU¿HOG WULSVIRUQRQJHRORJLVWVDQG(DUWKVFLHQFHWHDFKHUV,WZDVXVHGPRVWUHFHQWO\IRUDJURXSRI(DUWKVFLHQFH WHDFKHUVLQ)HEUXDU\DQGKDVEHHQUHYLVHGDJDLQIRUWKLVWULS 7KHJXLGHFRQWDLQVDQLQWURGXFWRU\VHFWLRQWKDWSURYLGHVVRPHIXQGDPHQWDOEDFNJURXQGIROORZHGE\D VHFWLRQFRQWDLQLQJWKHGLVFXVVLRQRIHDFK¿HOGWULSVWRS<RXZLOOVHHWKDW,WU\WREULQJRXWSDUWLFXODUSRLQWV 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9DOOH\DQG5LGJH7KLVURFNXQLWFRPSULVHVWKH¿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ontinental shelf Younger rocks not shown Middle Ordovician basin (b) Chickamauga Group limestone (W) & s hale (E) Wilhite slate & sandstone Sevier Shale Knox Group dolomi te and limeston (& sandstone) e (Stop 1) Conasauga Group Shale Rome Formation shale & sandstone(W) & Limestone (E) Dean Formation sandstone Shady Dolomite (Stop 2) unnamed conglomerate, & slate Chilhowee Group sandstone, shal thrust e fault (Stop 1) Wilhite slate & s andstone Rifted continental (Stops 3, 9, & 10) Miller Wilhite slate & sandstone Cove margin Dean Formation thrust & older rocks fault Rome Formation shale (Great Smoky Group) Hatcher Shady Dolomite (Stops 4 & 11) 2 Chilhowee Group sandstone, shale Great Smoky thrust Continental shelf Atlantic Ocean Sevier Shale 0 fault TR J (& sandstone) TR J K T J 5.5 seismic layer 2 10 Peri–Gondwanan Oceanic 5.6 crust 6.3 6.3 J 6.9 rocks Volcanic rocks seismic layer 3 7.2 ic 7.0 crust Moho Knox Group J 6.7 J Ocean 8.1 Rift-stage 7.2 crust 7.5 8.1 Modified from Klitgord et al., 1995, DNAG Transect E3 dolomite and limestone 20 (c) Rifted continental margin (a) Figure 1. Three perspectives of continental margins. (a) Deformed margin as seen on the field trip simplified into a column. (b) Ancient North American margin in eastern Tennessee (was actually facing south, rather than