DOCSLIB.ORG

Thesis Structural Evolution of the Potosí Uplift, Sierra

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Thesis Structural Evolution of the Potosí Uplift, Sierra THESIS STRUCTURAL EVOLUTION OF THE POTOSÍ UPLIFT, SIERRA MADRE ORIENTAL, NORTHEASTERN MEXICO Submitted by Stewart Alexander Williams Department of Geosciences In partial fulfillment of the requirements For the Degree of Master of Science Colorado State University Fort Collins, Colorado Fall 2019 Master’s Committee: Advisor: John Singleton John Ridley Melinda Laituri Copyright by Stewart Alexander Williams 2019 All Rights Reserved ABSTRACT STRUCTURAL EVOLUTION OF THE POTOSÍ UPLIFT, SIERRA MADRE ORIENTAL, NORTHEASTERN MEXICO The Jurassic Minas Viejas Formation is host to a Late Cretaceous to early Paleogene-aged décollement in the Sierra Madre Oriental, Mexico. The Minas Viejas Formation is dominated by rheologically-weak evaporite that accommodated thin-skinned deformation, forming the Sierra Madre Oriental fold-thrust belt with minimal deformation to the underlying Triassic-Jurassic red beds. Thin-skinned shortening above the décollement temporally transitioned to thick-skinned shortening, resulting in exhumation of the décollement and development of the Potosí uplift, one of the largest and well exposed thick-skinned uplifts in the orogen. Detailed geologic mapping and structural analysis provide insight into the geometry and kinematics of the Potosí uplift, and (U-Th)/He thermochronometry and vitrinite reflectance record the burial history and timing of exhumation associated with the uplift. Thick-skinned deformation involved folding of sub-décollement strata into a NNW-SSE- striking anticlinorium, development of cleavage, ENE-WSW directed thrust faulting, conjugate strike-slip faulting, and formation of ENE-WSW-striking extension fractures associated with barite mineralization. These structures consistently record ENE-directed subhorizontal shortening. Shortening is directed ~062° in the southern part of the uplift and ~077° in the northern part of ii the uplift. Thick-skinned deformation modified pre-existing geometries of thin-skinned folds involving Cretaceous overburden strata above the Jurassic evaporite décollement. Zircon (U-Th)/He cooling dates (ZHe) and vitrinite reflectance data indicate that the entire evaporite décollement was buried to ≥185°C, consistent with development of phyllitic fabrics in the basal part of the Minas Viejas Formation. Paleocene to mid-Eocene zircon (U-Th)/He cooling dates in the Triassic-Jurassic red beds below the evaporite décollement directly record the timing of exhumation associated with thick-skinned deformation, and suggest that the thick-skinned uplift was a continuation of earlier thin-skinned shortening as opposed to a distinct tectonic event. A zircon (U-Th)/He date from the southern Potosí uplift is ~66 Ma, whereas ZHe dates in the northern part of the uplift range from ~49–43 Ma. Two samples from the nearby Aramberri uplift to the south of the Potosí uplift have mean ZHe dates of ~63–54 Ma. The transition from thin- to thick-skinned shortening may be attributed to the evolution of mechanical stratigraphy in the décollement. Thin-skinned detachment folding resulted in significant migration of evaporite away from synclinal keels, effectively eliminating a planar weak zone at the base of the décollement and creating salt welds between carbonates or shales within the décollement with underlying red beds. The along-strike differences in timing of thick-skinned exhumation and the shortening directions may also be attributed to differences in mechanical stratigraphy. Thicker intervals of evaporite in the northern part of the uplift allowed thin-skinned shortening to continue while the southern part of the uplift transitioned to thick-skinned shortening as the weak evaporite décollement was exhausted. As a result, stress-strain trajectories in the northern part of the uplift refracted clockwise towards the area with more propagation of deformation. iii Our findings provide a new insight into the geometry, kinematics, and timing of deformation associated with the Potosí uplift, and may provide a framework for studying other thick-skinned uplifts in the Sierra Madre Oriental, and more generally orogenic belts that record a transition in deformation styles. iv ACKNOWLEDGEMENTS First and foremost, unbelievably huge thanks to Dr. John Singleton, my advisor. He was an invaluable resource, a wealth of knowledge, and constantly pushed to make the project better. He taught me there were always more measurements to take to strengthen the dataset, and to strive to present the best possible product I could. His constant optimism was a necessary aspect to this project. I thank my committee members, Dr. John Ridley and Dr. Melinda Laituri, for providing feedback on the thesis, elevating this project to a higher level through their experience and expertise. I thank the Singleton Research Group, my dear friends Skyler Mavor, Nikki Seymour, and Mike Prior, for being examples of extraordinary geologists and for being wonderful friends. Special thanks to Crossy for coming out and showing us around Mexico. He laid the foundations for this project and showed me just how wild evaporite structures can be. I thank my field assistants, Blake Franklin, Mike Wyatt, and Oscar Vazquez, for joining me in the middle of Mexico to look at some rocks, get stung by cacti, and live amongst the goats for weeks at a time. I thank Aliza Risby, my partner and anchor, for standing by me through thick and thin. I owe thanks to the graduate students in the Department of Geosciences for providing me with valuable friendship and support. And finally, this project wouldn’t have been possible if not for the American Chemical Society Petroleum Research Fund’s New Directions Grant. v DEDICATION I dedicate this thesis to my sister, who has always been there for me. vi TABLE OF CONTENTS ABSTRACT .........................................................................................................................................ii ACKNOWLEDGEMENTS .................................................................................................................... v DEDICATION .................................................................................................................................... vi LIST OF TABLES ................................................................................................................................ ix LIST OF FIGURES ............................................................................................................................... x INTRODUCTION ............................................................................................................................... 1 GEOLOGIC BACKGROUND ............................................................................................................... 4 1. Thin-skinned Shortening .................................................................................................. 4 2. Thick-skinned Uplift .......................................................................................................... 7 3. The Potosí Uplift ............................................................................................................. 10 METHODS ...................................................................................................................................... 14 4. Geologic Mapping of the Potosí Uplift ........................................................................... 14 5. Geometric and Kinematic Analysis ................................................................................. 15 6. Analysis of Burial and Exhumation History .................................................................... 16 6.1. (U-Th)/He Thermochronometry ................................................................................. 16 6.2. Vitrinite Reflectance ................................................................................................... 17 STRATIGRAPHY .............................................................................................................................. 19 7. Upper Triassic El Alamar Formation ............................................................................... 19 8. Upper Jurassic La Joya Formation .................................................................................. 22 9. Upper Jurassic Minas Viejas Formation ......................................................................... 24 9.1. Basal Stratigraphy of the Minas Viejas Formation – The La Nieve and Río de San José Members ............................................................................................................................... 28 10. Upper Jurassic – Cretaceous Strata ................................................................................ 32 10.1. Upper Jurassic – Lower Cretaceous La Casita Formation ....................................... 32 10.2. Lower Cretaceous Taraises Formation ................................................................... 33 10.3. Lower Cretaceous Tamaulipas Group ..................................................................... 34 10.4. Undifferentiated Upper Cretaceous Carbonates .................................................... 35 STRUCTURAL GEOLOGY OF THE POTOSÍ UPLIFT ........................................................................... 36 vii 11. Structures within the Jurassic-Cretaceous Overburden ................................................ 36 12. Structures within the Minas Viejas Formation Décollement ......................................... 44 12.1. Supradécollement ..................................................................................................
Load more

Recommended publications
  • First Occurrence of a Gigantic Pliosaurid Plesiosaur in The
    Bull. Soc. géol. Fr., 2003, t. 174, no 3, pp. 271-278 First occurrence of a gigantic pliosaurid plesiosaur in the late Jurassic (Kimmeridgian) of Mexico MARIE-CÉLINE BUCHY1,EBERHARD FREY2,WOLFGANG STINNESBECK1 &JOSÉ GUADALUPE LÓPEZ-OLIVA3 Key words. – Kimmeridgian, Pliosauridae, Mexico, Palaeobiogeography. Abstract. – Reinvestigation of a partial vertebral column from the Kimmeridgian La Caja Formation of Mexico, housed in the University of Linares (Mexico), and previously attributed to a dinosaur, proves to be from a very large pliosaurid plesiosaur. This specimen represents the first plesiosaur described from the Jurassic of Mexico. Its length has been esti- mated at 15 metres and, as a juvenile, is considered to be one of the largest Jurassic marine reptiles. The remains of this animal are here described. The morphology of the vertebral column is not diagnostic beyond family level. Large pliosaur vertebrae of a similar size are known from the Upper Jurassic of Europe, and are often referred to the genera Liopleurodon or Simolestes but these identifications are based only upon the size of the centra and have no taxonomic justification. A portion of rostrum with teeth was discovered together with the vertebral column but is unfortunately now lost. The Mexican pliosaur fills geographical and chronological gaps between western Tethys and South American pliosaurs, and is an additional support to the hypothesis of a Hispanic corridor linking at least temporarily the NW Euro- pean marine province with the western South American marine (Pacific) realm during the late Jurassic. Première occurrence d’un plésiosaure pliosauride géant dans le Jurassique supérieur (Kimméridgien) du Mexique Mots clés.
    [Show full text]
  • Boletín De La Asociación Mexicana De Geólogos Petroleros, A.C
    BOLETÍN DE LA ASOCIACIÓN MEXICANA DE GEÓLOGOS PETROLEROS, A.C. VOLUMEN LXII NÚMERO 1 ENERO-JUNIO 2020 NÚMERO 1, ENERO-JUNIO 2020. N 1300 El Madrono 00 16 0 0 1400 2 1 1100 1300 La Anacahuita 1200 1100 10 00 9 00 El Huizachal ‘ 1 4 0 0 1 300 1200 0 1100 0 0 1 La Joya Verde 1000 Cementerio 1 000 Aguas de Minas 0021 1200 13 1100 00 1400 12 00 1300 Explanation Undifferentiated Cretaceous strata (Ku) La Casita Formation (Jc) Olvido Formation (Jo) Novillo Formation (Jn) BOLETÍN DE LA ASOCIACIÓN MEXICANA GEÓLOGOS PETROLEROS, A.C. VOLUMEN LXII, La Joya Formation (Jlj) Rhyollite (Ji) La Boca Formation La Boca Formation upper member (Jlbs) lower member (Jlbi) Geologic contact Locality Symbols Inferred geological Coordinate system: UTM contact School Topografic base map from INEGI: CiudadVioctoria F-14-A-20 INSTRUCCIONES A LOS AUTORES El Boletín de la Asociación Mexicana de Geólogos Petroleros es una publicación semestral dedicada a la divulgación de artículos sobre geología, especialmente aquellos relacionados con la aplicación de las geociencias a la industria petrolera. Los trabajos factibles a publicarse se pueden dividir en tres tipos principales: Reportes de investigación originales, no publicados con anterioridad, que no excedan de 25 cuartillas. Notas técnicas originales que no excedan de 10 cuartillas. Notas técnicas de divulgación que no exceden de 10 cuartillas. Los trabajos deberán enviarse a: COMISIÓN DE ESTUDIOS TÉCNICOS Ernesto Cabalero García [email protected] Leonardo Enrique Aguilera Gómez [email protected] Dionisio Figueroa Rodríguez [email protected] En caso de que el trabajo sea aceptado, la Comisión de Estudios Técnicos turnará el mismo a la Comisión Editorial, quien se encargará de su preparación y adecuación para su publicación.
    [Show full text]
  • Place Names: an Analysis of Published Materials
    DOCUMENT RESUME ED 319 675 SO 020 925 AUTHOR Anderson, Paul S. TITLE Seeking a Core of Wo' -'d Regional Geography Place Names: An Analysis of Published Materials. PUB DATE 14 Oct 89 NOTE 18p.; Paper presentel at the Annual Meeting of the National Council for Geographic Education (Hershey, PA, October 11-14, 1989). Updated April 1990. PUB TYPE Speeches/Conference Papers (150) -- Reference Materials - Geographic Materials (133) -- Information Analyses (070) EDRS PRICE MF01/PC01 Plus Postage. DESCRIPTORS Elementary Secondary Education; *Geographic Location; *Geography Instruction; *Minimum Competencies; *Physical Geography IDENTIFIERS Place Names ABSTRACT Knowing place names is not the essence of geography, but some knowledge of names of geographical locations is widely considered to be basic information. Whether used in general cultural literacy, lighthearted Trivial Pursuit, educational sixth grade social studies, or serious debates on world events, place names and their locations are assumed to be known. At the college level of world regional geography courses, five books with lists of place names are in print by geographers: Fuson; MacKinnon; Pontius and Woodward; DiLisio; and Stoltman. Those five sources plus place name lists by P.S. Anderson and from Hirsch reveal similarities and diversities in their content. A core list of place names is presented with several cross-classifications by region, type of geographic feature, and grade level of students. The results reveal a logical progression of complexity that could assist geography educators to increase student learning and avoid duplication of efforts. There will never be complete agreement about any listing of the core geographical place names, but the presented lists are intended to stimulate discussion along constructive avenues.
    [Show full text]
  • Central Region of the Sierra Madre Oriental Executive Summary
    CLIMATE CHANGE ADAPTATION PROGRAMME FOR THE CENTRAL REGION OF THE SIERRA MADRE ORIENTAL EXECUTIVE SUMMARY Climate change poses a growing threat to Mexico’s ecosystems and communities. Cou- pled with climate variability and socio-economic factors, such as changes in land use, it has adverse effects on ecosystems and livelihoods in rural communities. Regional and local planning tools are therefore required to implement climate change adaptation and mitigation strategies. One example is the Central Region of the Sierra Madre Oriental mountain range (RCSMO, for its initials in Spanish), whose biodiversity-rich ecosystems are vulnerable to climate change. This has an impact on local communities, because their livelihoods depend pri- marily on the area’s natural resources. Hence it is vitally important to assess the resilience of the ecosystems and the ability of local communities to cope with the effects of climate change. In 2010, the National Commission of Natural Protected Areas (CONANP) responded by developing the Climate Change Strategy for Protected Areas (ECCAP). The Climate Change Adaptation Programme for the Central Region of the Sierra Madre Oriental (PACC-RCSMO) is an essential part of this project. The area of intervention is ap- proximately 2.15 million hectares, covering parts of the states of Tamaulipas, San Luis Po- tosí, Hidalgo, Puebla and Veracruz and portions of three major river basins� which drain into the Gulf of Mexico (Pánuco, San Fernando-Soto la Marina and northern Veracruz). Four natural protected areas (NPAs) were established in the RCSMO region. Three of them are federal NPAs and the fourth NPA is set to be declared.
    [Show full text]
  • Regional Economic Adjustment Plan for Building Disaster Resilient Communities US Department of Commerce – Economic Development Administration Grant No
    Lower Rio Grande Valley Regional Economic Adjustment Plan For Building Disaster Resilient Communities US Department of Commerce – Economic Development Administration Grant No. 08-79-04390 Prepared for: Lower Rio Grande Valley Development Council Hurricane Dolly July 23, 2008 Prepared by: Program Manager: Daniel O. Rios, PE Senior Project Manager: Sharlotte L. Teague, PE Project Engineer: Mardoqueo Hinojosa, PE Engineering Assistant: Ryan Hall, EIT In association with: 2012 Bickerstaff Heath Delgado Acosta, LLP Civil Systems Engineering, Inc. Guzman & Muñoz Engineering and Surveying, Inc. L&G Consulting Engineers, Inc. Olivarri & Associates, Inc. Rigcatco Consulting TEDSI Infrastructure Group, Inc. September 28, 2012 LOWER RIO GRANDE VALLEY DEVELOPMENT COUNCIL Regional Economic Adjustment Plan for Building Disaster Resilient Communities September 2012 LOWER RIO GRANDE VALLEY DEVELOPMENT COUNCIL Regional Economic Adjustment Plan for Building Disaster Resilient Communities EDA Grant No. 08-79-04390 TABLE OF CONTENTS Page EXECUTIVE SUMMARY……………………………………………………………… e1~e6 SECTION 1 INTRODUCTION 1.1 BACKGROUND ………………………….………..………………………..……… -1 1.2 PLAN FRAMEWORK………..…………..……….………………………………….-1 1.3 OBJECTIVES IMPLEMENTED IN THE DEVELOPMENT OF THE PLAN … -2 1.4 TEXAS DEPARTMENT OF RURAL AFFAIRS………………………………. -2 SECTION 2 BASELINE CONSIDERATIONS 2.1 PROJECT STUDY AREA………...…..…………………….……..……. -3 2.2 JURISDICTIONAL INTEREST AND COOPERATION……………..… -4 2.3 OVERSIGHT, INPUT, AND EXPECTATIONS …………………...…… -5 2.3(a) Plan Development Oversight / Team…………………………...……
    [Show full text]
  • First Record of Duvaliaex. Gr. Lata(Cephalopoda, Coleoidea) From
    First record of Duvalia ex. gr. lata (Cephalopoda, Coleiodea) from Mexico 527 BOLETÍN DE LA SOCIEDAD GEOLÓGICA MEXICANA VOLUMEN 65, NÚM. 3, 2013, P. 527-531 D GEOL DA Ó E G I I C C O A S 1904 M 2004 . C EX . ICANA A C i e n A ñ o s First record of Duvalia ex. gr. lata (Cephalopoda, Coleoidea) from Mexico Patrick Zell1,*, Seija Beckmann1, Wolfgang Stinnesbeck1, José Flores-Ventura2 1 Institute for Earth Sciences, Heidelberg University, Im Neuenheimer Feld 234, 69120 Heidelberg, Germany. 2 Santa Engracia 257, Fracc. Santa Elena, Saltillo C.P. 25015, Coahuila, México. * [email protected] Abstract Here we present the first record of the belemniteDuvalia ex. gr. lata (Cephalopoda, Coleoidea) from Mexico. The unique individual, a well-preserved rostrum, was discovered in Early Cretaceous strata of the Sierra de Parras close to Viesca in southwestern Coahuila. Duvalia ex. gr. lata was previously known from the Mediterranean Tethys. Our report extends the paleogeographic distribution of Duvalia to the western hemisphere and supports the hypothesis that the Hispanic Corridor was open during the Early Cretaceous, allowing for marine faunal exchange and migration between the Gulf of Mexico and the European Tethys. Keywords: Duvalia, belemnite, Early Cretaceous, Mexico, Hispanic Corridor. Resumen Se reporta por primera vez el belemnite Duvalia ex. gr. lata (Cephalopoda, Coleoidea) en México. El único ejemplar, un rostro bien preservado, ha sido descubierto en capas del Cretácico Temprano de la Sierra de Parras,en las cercanías de Viesca, en el suroeste de Coahuila. Previamente, se conocía a Duvalia ex.
    [Show full text]
  • Fundamental Biogeographic Patterns Across the Mexican Transition Zone: an Evolutionary Approach
    Ecography 33: 355Á361, 2010 doi: 10.1111/j.1600-0587.2010.06266.x # 2010 The Author. Journal compilation # 2010 Ecography Subject Editor: Douglas A. Kelt. Accepted 4 February 2010 S YMPOSIUM ON Fundamental biogeographic patterns across the Mexican Transition Zone: an evolutionary approach Juan J. Morrone J. J. Morrone ([email protected]), Museo de Zoologı´a ‘‘Alfonso L. Herrera’’, Depto de Biologı´a Evolutiva, Fac. de Ciencias, Univ. Nacional Auto´noma de Me´xico (UNAM), Apartado postal 70-399, 04510 Mexico, D.F., Mexico. B IOGEOGRAPHIC Transition zones, located at the boundaries between biogeographic regions, represent events of biotic hybridization, promoted by historical and ecological changes. They deserve special attention, because they represent areas of intense biotic interaction. In its more general sense, the Mexican Transition Zone is a complex and varied area where Neotropical and Nearctic biotas overlap, from southwestern USA to Mexico and part of Central America, extending south to the Nicaraguan lowlands. In recent years, panbiogeographic analyses have led to restriction of the Mexican Transition Zone to the montane areas of Mexico and to recognize five smaller biotic components within it. A cladistic biogeographic analysis challenged the hypothesis that this transition zone is biogeographically divided along a north-south axis at the Transmexican Volcanic Belt, as the two major clades found divided Mexico in an east-west axis. This implies that early Tertiary geological events leading to the convergence of Neotropical and Nearctic elements may be younger (Miocene) B than those that led to the east-west pattern (Paleocene). The Mexican Transition Zone consists of five biogeographic OUNDARIES provinces: Sierra Madre Occidental, Sierra Madre Oriental, Transmexican Volcanic Belt, Sierra Madre del Sur, and Chiapas.
    [Show full text]
  • Occurrence of Torvoneustes (Crocodylomorpha, Metriorhynchidae) in Marine Jurassic Deposits of Oaxaca, Mexico
    Rev. bras. paleontol. 19(3):415-424, Setembro/Dezembro 2016 © 2016 by the Sociedade Brasileira de Paleontologia doi: 10.4072/rbp.2016.3.07 OCCURRENCE OF TORVONEUSTES (CROCODYLOMORPHA, METRIORHYNCHIDAE) IN MARINE JURASSIC DEPOSITS OF OAXACA, MEXICO JAIR I. BARRIENTOS-LARA Posgrado en Ciencias Biológicas, Instituto de Geología, Universidad Nacional Autónoma de México, Circuito de la Investigación S/N, Ciudad Universitaria, Delegación Coyoacán, Distrito Federal, 04510, México. [email protected] YANINA HERRERA, MARTA S. FERNÁNDEZ División Paleontología Vertebrados, Unidades de Investigación Anexo Museo, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Av. 60 y 122, B1900AVW, La Plata, Argentina. [email protected], [email protected] JESÚS ALVARADO-ORTEGA Instituto de Geología, Universidad Nacional Autónoma de México, Circuito de la Investigación s/n, Ciudad Universitaria, Delegación Coyoacán, Distrito Federal, 04510, México. [email protected] ABSTRACT – IGM 9026 is a singular fossil collected at the beginning of the 20th century in an improperly documented site within the Tlaxiaco Basin, near to Tlaxiaco town, Oaxaca, Mexico. The age of the site was suggested as being early Cretaceous. This specimen is the holotype of Plesiosaurus (Polypticodon) mexicanus, which later was identified as a possible late Jurassic marine crocodylomorph of the family Metriorhynchidae, and consequently it was referred as ?Cricosaurus mexicanus. The present study provides a re-description of this fossil based on a microscopic analysis and the use of white and UV lights; these analyses led to the discovery of peculiar dental characters diagnostic of the genus Torvoneustes. This finding supports the re-classification of IGM 9026 under a new nominal combination asTorvoneustes mexicanus.
    [Show full text]
  • Kimmeridgian (Late Jurassic) Cold-Water Idoceratids (Ammonoidea) from Southern Coahuila, Northeastern Mexico, Associated with Boreal Bivalves and Belemnites
    REVISTA MEXICANA DE CIENCIAS GEOLÓGICAS Kimmeridgian cold-water idoceratids associated with Boreal bivalvesv. 32, núm. and 1, 2015, belemnites p. 11-20 Kimmeridgian (Late Jurassic) cold-water idoceratids (Ammonoidea) from southern Coahuila, northeastern Mexico, associated with Boreal bivalves and belemnites Patrick Zell* and Wolfgang Stinnesbeck Institute for Earth Sciences, Heidelberg University, Im Neuenheimer Feld 234, 69120 Heidelberg, Germany. *[email protected] ABSTRACT et al., 2001; Chumakov et al., 2014) was followed by a cool period during the late Oxfordian-early Kimmeridgian (e.g., Jenkyns et al., Here we present two early Kimmeridgian faunal assemblages 2002; Weissert and Erba, 2004) and a long-term gradual warming composed of the ammonite Idoceras (Idoceras pinonense n. sp. and trend towards the Jurassic-Cretaceous boundary (e.g., Abbink et al., I. inflatum Burckhardt, 1906), Boreal belemnites Cylindroteuthis 2001; Lécuyer et al., 2003; Gröcke et al., 2003; Zakharov et al., 2014). cuspidata Sachs and Nalnjaeva, 1964 and Cylindroteuthis ex. gr. Palynological data suggest that the latest Jurassic was also marked by jacutica Sachs and Nalnjaeva, 1964, as well as the Boreal bivalve Buchia significant fluctuations in paleotemperature and climate (e.g., Abbink concentrica (J. de C. Sowerby, 1827). The assemblages were discovered et al., 2001). in inner- to outer shelf sediments of the lower La Casita Formation Upper Jurassic-Lower Cretaceous marine associations contain- at Puerto Piñones, southern Coahuila, and suggest that some taxa of ing both Tethyan and Boreal elements [e.g. ammonites, belemnites Idoceras inhabited cold-water environments. (Cylindroteuthis) and bivalves (Buchia)], were described from numer- ous localities of the Western Cordillera belt from Alaska to California Key words: La Casita Formation, Kimmeridgian, idoceratid ammonites, (e.g., Jeletzky, 1965), while Boreal (Buchia) and even southern high Boreal bivalves, Boreal belemnites.
    [Show full text]
  • Upper Jurassic (Lower Kimmeridgian-Olvido) Carbonate Strata from the La Popa Basin Diapirs, NE Mexico
    BOLETÍN DE LA SOCIEDAD GEOLÓGICA MEXICANA OLUMEN NÚM P V 63, . 2, 2011, . 313-321 D GEOL DA Ó E G I I C C O A S 1904 M 2004 . C EX . ICANA A C i e n A ñ o s Upper Jurassic (Lower Kimmeridgian-Olvido) carbonate strata from the La Popa Basin diapirs, NE Mexico Francisco J. Vega1, *, Timothy F. Lawton2 1 Instituto de Geología, Universidad Nacional Autónoma de México. Ciudad Universitaria, 04510 Coyoacán, México, D. F. 2 Institute of Tectonic Studies, New Mexico State University. Las Cruces, New Mexico 88003, United States of America * [email protected] Abstract Carbonate strata that occur as blocks encased in gypsum of three different salt diapirs in La Popa Basin contain a single invertebrate fauna indicating a Late Jurassic (Kimmeridgian) age for all sampled fossiliferous blocks. The most biostratigraphically significant species, present in all diapirs, is the gryphaeid oyster Nanogyra virgula. Other species identified in the blocks include the bivalves Astarte gracilicostula, Cercomya durangensis, Myophorella sp., Grammatodon sp. and the nautiloid Cymatoceras? sp. Geologic relations of the entire assemblage of carbonate blocks, including nodular gypsum interbedded with the fossiliferous beds, salt casts in micrite of the blocks, random structural position of blocks within the diapiric evaporite, absence of blocks younger than Early Kimmeridgian in the diapirs, and regional stratigraphic relations, suggest that the carbonate strata were originally interbedded with, or directly overlie, evaporite strata. This inference is corroborated by the presence of Nanogyra virgula (previously reported as Exogyra cf. E. susplicifera) in carbonate strata directly overlying massive gypsum at Potrero Minas Viejas, adjacent to La Popa Basin.
    [Show full text]
  • Structural Traverse Across the Sierra Madre Oriental Fold-Thrust Belt in East-Central Mexico: Alternative Interpretation and Reply
    Structural traverse across the Sierra Madre Oriental fold-thrust belt in east-central Mexico: Alternative interpretation and reply Alternative interpretation JOSE F. LONGORIA The University of Texas at Dallas, Programs in Geosciences, Box 830688, Richardson, Texas 75083-0688 INTRODUCTION The geology of Mexico is enigmatic mainly because of the lack of For example, in his sections a and c, the lithic package overlying the field work addressing basic aspects of geological research, including re- Las Trancas is referred to as the "Tamaulipas Formation" [sic !]. On the gional stratigraphy and paleogeographic analysis, which are fundamental basis of pioneering studies by Segerstrom (1956,1961a, 1961b, 1962), as to unraveling the structure and tectonics of the Mexican Cordillera. In my well as my own regional studies (Longoria, 1975,1984a, 1984b), there are opinion, it is necessary to have a proper stratigraphic framework before the no outcrops of Tamaulipas Limestone to the west or the east of the "El structure of the Sierra Madre Oriental can be correctly balanced. Although Doctor bank"; instead, a near time equivalent of it, the Santuario, was Suter's paper (1987) represents an excellent attempt to display the geologic defined by Segerstrom in 1961 to include those carbonate rocks. Substitu- complexity of part of the Sierra Madre Oriental, there are basic strati- tion of the Tamaulipas for the Santuario should be documented in com- graphic and structural aspects that deserve further treatment because they parative field studies of both stratotypes and should follow the precepts may yield an alternative interpretation to Suter's structural analysis, as established by the North American Stratigraphic Code (North American well as to his attempt to extrapolate the surface features to the basement.
    [Show full text]
  • West Texas Geological Society Publications and Contents Purchase from West Texas Geological Society
    West Texas Geological Society Publications and Contents Purchase from West Texas Geological Society: http://www.wtgs.org/ 77-68 Geology of the Sacramento Mountains Otero County, New Mexico Regional Distribution of Phylloid Algal Mounds in Late Pennsylvanian and Wolfcampian Strata of Southern New Mexico James Lee Wilson Growth History of a Late Pennsylvanian Phylloid Algal Organic Buildup, Northern Sacramento Mains, New Mexico D.F. Toomey, J.L. Wilson, R. Rezak Paleoecological Evidence on the Origin of the Dry Canyon Pennsylvanian Bioherms James M. Parks Biohermal Submarine Cements, Laborcita Formation (Permian), Northern Sacramento Mountains, New Mexico John M. Cys and S.J. Mazzullo Carbonate and Siliciclastic Facies of the Gobbler Formation John C. Van Wagoner The Rancheria Formation: Mississippian Intracratonic Basinal Limestones Donald A. Yurewicz Stratigraphic and Structural Features of the Sacramento Mountain Escarpment, New Mexico Lloyd C. Pray Conglomeratic Lithofacies of the Laborcita and Abo Formations ( Wolfcampian), North Central Sacramento Mountains: Sedimentology and Tectonic Importance David J. Delgado Paleocaliche Textures from Wolfcampian Strata of the Sacramento Mountains, New Mexico David J. Delgado Introduction to Road Logs Lloyd C. Pray Alamogordo to Alamo Canyon and the Western Sacramento Mountains Escarpment Field Guide and Road Log “A” Lloyd C. Pray Supplemental Field Guide to Southernmost Sacramento Mountains Escarpment – Agua Chiquita and Nigger Ed Canyons Lloyd C. Pray Alamogordo to Indian Wells Reentrant Field Guide and Road Log “B” Lloyd C. Pray Guide Locality B-1-West End of Horse Ridge John C. Van Wagoner 1 Field Guide and Road Log “C” Lloyd C. Pray Plate Shaped Calcareous Algae in Late Paleozoic Rocks of Midcontinent (abstract): James M.
    [Show full text]