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Index Note: Page numbers in bold type refer to Tables, those in italic type refer to illustrations, diagrams etc Ab-An-Or diagram, Sierras Pampeanas 353 Appalachian-Ouachita orogenic belt 226 Acadian orogeny 77, 156, 228 Appalachians Acado-Baltic Province 68 Chepultepec interval 42 Acanthotoechia 64, 73 correlation with 5, 14, 57, 77 accretionary prisms 137 deformation 156 accretionary stages 3, 13, 70, 75, 226 internal basement massifs 15 Achala batholith 184, 185, 338 mobile belts 219 Achalian orogeny 261,278 passive margin 16, 74 actinolite-tremolite 286 rift-drift transition 213 active margin Taconic orogeny 225 227 Famatina System 72, 222, 285 Appohimchi Subprovince 77 major element evidence 138 apron, volcaniclastic 128 advective transfer 223 Ar/Ar dating Aegiromena 65, 67, 70 analytical methods 267, 298 AFM diagram, Famatina plutons 288 Chilenia collision 177 Afro-South American brachiopod Realm 77 micas 273-275 aggradational environment 52 Sierra de Fiambalfi 308, 316 agnathans 65, 70 Sierras Pampeanas 147-149, 150-151,152-153, 154, Ahtiella Zone 64 155, 222, 261,268 Alabama-Oklahoma transform fault 18 spectra 274 Alcaparrosa Formation 24 Arbuckle Limestone 64 pillow-lavas 95 arc accretion 228 algae 42, 90 arc splitting 178 allochthons, Precordillera 1, 11, 27 arc system, Ordovician basin 127 Alsate Shale 93 Archaeorthis Zone 63 Altai Hinggan mobile belt 63 Arenig brachiopods alumina saturation index diagram 352 Famatina and Central Andean basin 62 Amazonia 73, 77, 211 Precordillera 61 American Realm 62 Arequipa-Antofalla craton amphibole barometry, Sierra de Fiambalfi 303 and Amazonian craton 211 amphibolite-facies metamorphism collision 76, 220, 251 Sierra de Fiambalfi 303-305, 313, 321 distinctness 6 Sierra de Pie de Palo 159, 160, 177 isotopic ages 73 amphibolites Occidentalia terrane 5 MORB signatures 212 supercontinent break-up 212 Sierra de Pie de Palo 160, 168, 172 Argentina Sierra de San Luis 236 geological map 298 spider diagram 187 geological provinces 86 anatexis Precordillera 1 E1 Pil6n 204, 207, 208, 210 Arica embayment 73,220 Famatina System 286 Artejia mega-continent 70 Olta 275 Asaphiscus 68 Sierra de Chepes 350 ash beds Sierras de Cdrdoba 228 intercalation 20, 27 Ancasti 297 Precordillera 107 Anchoramena 65 ash transport, direction 120 andalusite 241,242, 243 Asperezas Granite 351-352, 353, 362, 364 andalusite zone, Sierra de Chepes 349 aulacogens 15, 211 Andean cycle 2, 3 Avalonia terrane 73, 74, 76, 229 Andes, geological map 252 see also Carolina terrane andesite 92, 93, 96, 128 Avalonian faunas 49 Angaco belt 146 Anglesey 72 B. naris Zone 63, 66 Annamitella 73 Back Bay fauna 76 Anti-Atlas 66 back-arc environments Antirhynchonella fauna 76 Brasiliano orogeny 262 apatite 130 Famatina System 72 Apheorthis 66 Lau basin 170, 171 aplogranite 198 Pie de Palo complex 146, 175, 178 Aporthophyla 64 Precordillera basement 144 Appalachian basin 231 Puna 127 Appalachian-Caledonide orogen 72 Quebrada Guayaupa-Lima 173 370 INDEX back-arc environments (continued) Laurentia 63 Sierras de C6rdoba 214 Ordovician 14 spreading centres 172, 178 Precordillera 61, 63 back-arc protoliths, analyses 164-165 Brazil, cycles 3 Bahamas 20 Brazilian orogeny 73, 261 Balcarce Formation 111 break-up stages 3 Baltic Province 49, 57, 63, 64, 66 break-up unconformities 49, 52 Baltica, bentonites 86 breccias, hydroclastic 128 Baltica palaeocontinent 68 Brevard fault 226 barometry, GRIPS 307, 308 basalts discrimination diagrams 287 Caborca 231 lavas 128, 172 Cacheuta sub-basin 146 MORB-type 46, 48, 160 Cadomian terrane 229 basement rocks calc-alkaline plutons 225, 226, 277, 290, 318 Sierra de Pie de Palo 87, 143, 159 calc-silicate rocks 313 Sierra de San Luis 236 calcarenites 92 basic/ultrabasic belts 229 calcretes 40, 90 basin closure 21 Caledonian orogeny 76, 77 basin subsidence 128 Calingasta 108 bedforms 39 Calmayo 198 Belen schists 211 Cambrian, faunas 11 Be#ella 66 Camerella 64 Bemberg 241,327, 329 Campo Chico 77 K-bentonites 20, 21 Campylorthis 65 ages 110 Cafiani 228 Baltica 86 Cancafiiri Formation 67 comparative chart 120 Carlo del Oeste 77 comparative distribution 121 Carlo Grande Formation 77 dating 108 Capilla del Monte granite 184 Famatinean volcanic arc 121,229 Caradocian brachiopods 65 Fort Pefia 96 Precordillera and Central Andean basin 63 geochemistry 107, 115 Carap6 shear zone 185 localities 108, 109 carbonate facies, warm-water 71 Marathon 93, 96 carbonate rim, North America 20 mineralogy 111 carbonate sequences North America 121 Cambrian & Ordovician 14, 15, 35 Ordovician 7, 75 environmental reconstruction 23 Solitario 95 facies types 15 transects 110 Ordovician 20 whole-rock analyses 118-119 and rifting models 19, 219 see also meta-bentonites carbonate shoal complex 39 Big Bend 89 Carolina terrane 74, 75, 76, 226, 227, 229, 231 bioherms, distribution 98 cataclasis 160, 167 biostromes, San Juan Formation 43 catch-up system 41 biotite zone, Sierra de Chepes 349 cathodo-luminescence images 269 bioturbation 43 Caucete Group Birmingham graben 18, 19, 41 age of 160, 177 Bishop Tuff 113 contact 146 bivalves 66 Cuyania 88 black shales 75, 90 quartzites 155, 169 Black Warrior Basin 18 Sierra de Pie de Palo 98 block-faulting 20, 25, 92, 98, 100, 253 Celtic Province, brachiopods 57, 59, 63, 64, 72 Blue Ridge 18, 226, 227, 228, 229, 231 Central Andean basin, biogeography 66-67 Bonnia-Olenellus chron 51 Central Batholithic Belt 3, 184 boudinage 240, 247 Central Newfoundland volcanic sequence 73, 78 brachiopods Cerro Aspero batholith 184, 338 affinity variation 65 Cerro Barboza 146, 159, 160 assemblage zones 61 Cerro Blanco granites 290 dispersion 59, 70 Cerro La Chilca 109 Famatina and Central Andean basin 62 Cerro La Silla 91, 109 faunas 57, 59 Cerros Largos 242, 243, 332, 333 Gondwana 49 Cerro Negro 313, 314, 315 Hirnantian 65 Cerro Pelado 41, 90, 195 INDEX 371 Cerro Potrerillo 109 continental reconstruction Cerro San Jorge 143, 146-147 Cambrian 227 Cerro Toro granite 288 Early Ordovician 26 Cerro Totora Formation 17, 18, 38, 41, 51 continental rise 49 Cerro Totora graben 19 continental shelf, Laurentia 11 Cerro Valdivia 145, 155, 159, 160, 166 continental slope 49, 91, 96 Cerro Viejo 95, 109, 111, 114 contourites 46 Chafiic phase 3, 229 cooling, mid-Palaeozoic 313-314, 316-317 channel systems 128 cooling rates 312-313 Charlotte belt 226, 227, 231 coquinas 39 chemical index of alteration 131, 140 cordierite zone, Sierra de Chepes 349 Chepes Granodiorite 351,353, 362 cordieritite 197, 198, 207, 208 emplacement 365 Cordillera de la Costa 228 U-Pb dates 360 Cordillera Frontal 220 Chepes Porphyritic Granodiorite 351,353 Cordillera Oriental 66, 76 Chepultepec interval 42 Cordylodus cf. angulatus 43 chert beds 93 correlation chart, stratigraphic units 60 Chile trench 1 Cow Head Group 63 Chilenia terrane 5, 52, 155, 177, 220, 278 crenulation 184, 245, 250, 306 chromite 163, 166, 178 Crepicephalus Zone 62 chromitites 183 cross bedding 42 chronostratigraphic chart 16 cross-stratification, herringbone 39, 40 Clarkeia fauna 50, 52, 70 Crossiskenidium 66, 73 clastic rocks crust palaeocurrents 285 isotopic signatures 207 Puna 129 partial melting 292 clastic wedge, oceanic crust in 15 crustal extension clasts Cambrian 14, 51, 52 basement 45 Ordovician 99 volcanic 92, 93 supersequence C 48 Clavohamulus hintzei 63 crustal recycling 140 clay mineralogy crustal shortening 120 bentonites 111 crustal subsidence 44 Fort Pefia 97 crustal thickening 210, 212, 222, 224, 227, 228 Cliftonia oxoplecoides 65 Sierra de San Luis 337 climate, Ordovician 20 Cruz de Carla 243, 332, 333 climate indicators, Precordillera migration 14 Cruz del Eje complex 275 clinopyroxenes, compositional plot 115 Cruziana 111 clitambonitids 66 Cumbres Calchaquies 222 collision dates, Precordillera terrane 6-7, 12, 75 cumulates collision and exchange model 70 Cerro Barboza 175, 178 Colohuincul complex 224, 225, 228 Cerro Valdivia 168, 175, 178 compositional layering 305, 310 Mogote Corralitos 173 compressional deformation 50 Pie de Palo complex 160, 167, 171 Conglomerado Cafiada Honda 245 Quebrada del Gato 175, 178 conglomerates Sierra de Fiambalfi 312 chert-pebble 48, 49 Cuparius 63, 69 continental margin 46 Cushamen unit 225 mineral compositions 320 Cuyania terrane 3, 6, 36 Sierras Pampeanas 319 basement 44, 50, 220 wedged 24 carbonate platform 97 conjugate margins 17, 19, 59, 68, 213 collision 53, 155 Conlara Metamorphic Complex 236 components 87 conodont faunas 35, 43, 63 composite nature 147 in brachiopod zone calibration 61 drifting 253 contact metamorphism 306, 311,328 eastern margin 235, 253 continental arc systems 7, 131, 137, 139, 343, extent of 85 365 faunal exchange 68 continental bridges 14, 15 Grenvillean age 147 continental collision 1, 211,212, 214, 219 as 'Llanoria' 87 magma generation 338 plate rotation 100 continental lithosphere 14 rifting 177, 178 continental margins, Atlantic-type 47, 52 Cuyania-Gondwana suture 156, 253 continental platform, carbonate 13 Cuyo basin 146 372 INDEX dacite 92, 93, 128, 131, 174, 286 E1 Jaguelito-Nahuel Niyeu metapelites 225 Dagger Flat Sandstone 92, 93, 98 E1 Morro pluton 335, 336 Dalmanella testudinaria 65 E1 Paso Group 98 Davidsville Group 66 E1 Pefi6n Grande 335 debris flows 85 E1 Pil6n complex Los Sombreros Formation 21 age 204, 222, 276 volcaniclastic 93 concordia plot 208 deformation, compressive 241,242, 245, 253 emplacement 207 Degamella 66 metamorphism 185 dehydration melting 336 migmatites 193, 197 Deicke beds 121 monzogranite 183 depositional assemblages 38 El Quemada 178 descending slab, hydration of 292 El
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  • The Geology, Paleontology and Paleoecology of the Cerro Fortaleza Formation

    The Geology, Paleontology and Paleoecology of the Cerro Fortaleza Formation

    The Geology, Paleontology and Paleoecology of the Cerro Fortaleza Formation, Patagonia (Argentina) A Thesis Submitted to the Faculty of Drexel University by Victoria Margaret Egerton in partial fulfillment of the requirements for the degree of Doctor of Philosophy November 2011 © Copyright 2011 Victoria M. Egerton. All Rights Reserved. ii Dedications To my mother and father iii Acknowledgments The knowledge, guidance and commitment of a great number of people have led to my success while at Drexel University. I would first like to thank Drexel University and the College of Arts and Sciences for providing world-class facilities while I pursued my PhD. I would also like to thank the Department of Biology for its support and dedication. I would like to thank my advisor, Dr. Kenneth Lacovara, for his guidance and patience. Additionally, I would like to thank him for including me in his pursuit of knowledge of Argentine dinosaurs and their environments. I am also indebted to my committee members, Dr. Gail Hearn, Dr. Jake Russell, Dr. Mike O‘Connor, Dr. Matthew Lamanna, Dr. Christopher Williams and Professor Hermann Pfefferkorn for their valuable comments and time. The support of Argentine scientists has been essential for allowing me to pursue my research. I am thankful that I had the opportunity to work with such kind and knowledgeable people. I would like to thank Dr. Fernando Novas (Museo Argentino de Ciencias Naturales) for helping me obtain specimens that allowed this research to happen. I would also like to thank Dr. Viviana Barreda (Museo Argentino de Ciencias Naturales) for her allowing me use of her lab space while I was visiting Museo Argentino de Ciencias Naturales.
  • GSA TODAY • Radon in Water, P

    GSA TODAY • Radon in Water, P

    Vol. 8, No. 11 November 1998 INSIDE • Field Guide Editor, p. 5 GSA TODAY • Radon in Water, p. 10 • Women Geoscientists, p. 12 A Publication of the Geological Society of America • 1999 Annual Meeting, p. 31 Gas Hydrates: Greenhouse Nightmare? Energy Panacea or Pipe Dream? Bilal U. Haq, National Science Foundation, Division of Ocean Science, Arlington, VA 22230 ABSTRACT Recent interest in methane hydrates has resulted from the recognition that they may play important roles in the global carbon cycle and rapid climate change through emissions of methane from marine sediments and permafrost into the atmosphere, and in causing mass failure of sediments and structural changes on the continental slope. Their presumed large volumes are also consid- ered to be a potential source for future exploitation of methane as a resource. Natural gas hydrates occur widely on continental slope and rise, stabilized in place by high hydrostatic pressure and frigid bottom-temperature condi- tions. Change in these conditions, Figure 1. This seismic profile, over the landward side of Blake Ridge, crosses a salt diapir; the profile has either through lowering of sea level or been processed to show reflection strength. The prominent bottom simulating reflector (BSR) swings increase in bottom-water temperature, upward over the diapir because of the higher conductivity of the salt. Note the very strong reflections of may trigger the following sequence of gas accumulations below the gas-hydrate stability zone and the “blanking” of energy above it. Bright events: dissociation of the hydrate at its Spots along near-vertical faults above the diapir represent conduits for gas venting.