Pressure Dissolution Features in Oxfordian Microbial-Sponge Buildups with Pseudonodular Texture, Kraków Upland, Poland

Total Page:16

File Type:pdf, Size:1020Kb

Pressure Dissolution Features in Oxfordian Microbial-Sponge Buildups with Pseudonodular Texture, Kraków Upland, Poland Annales Societatis Geologorum Poloniae (2016), vol. 86: 355–377. doi: https://doi.org/10.14241/asgp.2016.008 PRESSURE DISSOLUTION FEATURES IN OXFORDIAN MICROBIAL-SPONGE BUILDUPS WITH PSEUDONODULAR TEXTURE, KRAKÓW UPLAND, POLAND Jacek MATYSZKIEWICZ & Alicja KOCHMAN AGH University of Science and Technology, Faculty of Geology, Geophysics and Environment Protection, al. Mickiewicza 30; 30-059 Kraków, Poland; e-mails: [email protected]; [email protected] Matyszkiewicz, J. & Kochman, A., 2016. Pressure dissolution features in Oxfordian microbial-sponge buildups with pseudonodular texture, Kraków Upland, Poland. Annales Societatis Geologorum Poloniae, 86: 355–377. Abstract: Part of the Oxfordian carbonate buildups in the southern part of the Kraków Upland is developed as pseudonodular limestones, which represent segment reefs. These limestones are composed of connected, roun- ded-oval to subangular carbonate pseudonodules. The pseudonodules, densely packed within the limestone, fall out easily under mechanical stress. The recently observed texture of pseudonodular limestones resulted from two stages of chemical compaction. During the first stage, in the Late Jurassic, high-amplitude and low-amplitude stylolites and dissolution seams were formed. The sites particularly favourable for the development of high-amplitude stylolites were the boun- daries between already lithified fragments of the laminar, rigid microbial-sponge framework. The low-amplitude stylolites formed mainly in the intercalated wackestone-packstone, which was lithified somewhat later; hence, the dissolution seams originated at the contacts between the rigid microbial-sponge framework and the wackestone- packstone. After Early Cretaceous erosion, which decreased the burial load, Late Cretaceous sedimentation enabled the renewal of pressure dissolution. Thus, some low-amplitude stylolites evolved into dissolution seams. In stylolites composed of both low- and high-amplitude segments, dissolution proceeded at the bases of interpenetrating high-amplitude stylolite columns, with the simultaneous transformation of low-amplitude stylolite segments into dissolution seams. These seams, which formed at the initial stage of chemical compaction, were subjected in turn to further pressure dissolution, giving rise to the formation of horsetail structures. The vertical stress field, which triggered the pressure dissolution processes, presumably resulted in the formation of high-angle and vertical incipient tension gashes. At the beginning of the processes, these gashes remained closed. In the Cenozoic, under the extensional regime generated by overthrusting Carpathian flysch nappes, some high-angle and vertical dissolution seams and low-amplitude stylolites opened up, forming defor- med dissolution seams and deformed stylolites. Under the same conditions, the high-angle and vertical tension gashes opened up as well. Subsequently, during the exposure period, unloading fractures developed, partly as a result of the opening of some subhorizontal and horizontal dissolution seams and stylolites. The unloading fractures, along with the already existing vertical and high-angle tension gashes, formed the network changing the limestone into pseudo- nodules of various shapes and sizes. The open spaces between the limestone fragments became local conduits for karst waters. Key words: Pressure dissolution features, pseudonodularity, microbial-sponge buildups, Oxfordian, southern Poland. Manuscript received 9 December 2015, accepted 16 May 2016 INTRODUCTION Pseudonodular limestone is defined as a rock composed densely packed within the limestone, falling out easily un- of densely packed, connected rounded-oval to subangular der mechanically induced stress. carbonate nodules (e.g., Hummel, 1960; Clari et al., 1984; Pseudonodular (Polish: zrostkowe) limestones are a pe- Dromart, 1989; Matyszkiewicz, 1994, 1997; Martire, 1996; culiar facies of the Upper Jurassic carbonates, common in Clari and Martire, 1996; Marok and Reolid, 2012). The the southern part of the Kraków Upland, in the Mników area boundaries between nodules are indistinct. The nodules are (Fig. 1). Spectacular exposures of pseudonodular limesto- 356 J. MATYSZKIEWICZ & A. KOCHMAN Fig. 1. Location of the Zimny Dó³ Nature Reserve superimposed on a geologic bedrock map after Gradziñski (2009). nes are known from the Zimny Dó³ Valley, near the village fects of bottom currents and later diagenetic transforma- of Czu³ów (Fig. 2). In 1991, thanks to the efforts of Profes- tions. In his interpretations, the currents removed some of sor Ryszard Gradziñski, an abiotic nature reserve was estab- the unlithified carbonate mud and supplied larger fossils, lished there. mostly small ammonites, siliceous sponges and brachio- The origin of the pseudonodular limestones of the Zimny pods. After deposition, diagenetic processes caused the re- Dó³ Valley was discussed by D¿u³yñski (1952) and Matysz- distribution of calcium carbonate, which accumulated kiewicz (1994, 1997) and also noted by Gradziñski (1972), around the fossils and formed concretions, enveloped in the Gradziñski and Bary³a (1986, 2005), and Gradziñski and sediment that was richer in clay. Musielewicz-Jasiñska (1992). Matyszkiewicz (1994, 1997) excluded the action of The pseudonodular limestones of the Mników area bottom currents; as the formative process of the pseudono- were described for the first time by D¿u³yñski (1952), who dular limestones, he proposed chemical compaction, affect- interpreted their origin as resulting from the combined ef- ing the inhomogeneous sediment, composed mostly of mi- PRESSURE DISSOLUTION FEATURES 357 Fig. 2. Sketch of Upper Jurassic tors in the Zimny Dó³ Nature Reserve (after Gradziñski and Bary³a, 2005) with location of pseudonodular limestones exposures. Points marked as A, B, and eastern and western corridors are outcrops described in detail. crobialites and calcified siliceous sponges, in which an ini- from an extension regime generated in the Cenozoic by tial, laminar rigid framework had developed (cf. Pratt, 1982). overthrusting Carpathian nappes, although their formation Furthermore, the principal role in the formation of the already had been initiated in the Late Jurassic or even earlier pseudonodular limestones was played by pressure dissolution (Matyszkiewicz, 1996; Zió³kowski, 2007; Krajewski et al., processes, which generated numerous pressure dissolution 2011). features (PDFs), separating the pseudonodules. During later The Zimny Dó³ Valley is located in the southern part of diagenetic stages, some PDFs were transformed owing to the the Kraków Upland, in the Tenczynek Horst, which borders combined action of solutions circulating within the rock for- on the Krzeszowice Graben to the south (Fig. 1). As a land- mation, karstification, and other weathering processes. form, the Zimny Dó³ Valley developed in the Palaeogene The paper below presents the development of pressure and was covered with loess in the Pleistocene (Gradziñski, dissolution features (PDFs) along with a detailed recon- 1962; D¿u³yñski et al., 1968). Among the typical morpho- struction of the processes, which led to the formation of re- logical features of the Zimny Dó³ area are suffosion sink- cently observed textures of the pseudonodular limestones. holes, the walls of which are composed of loess and the bot- toms of which are Upper Jurassic limestones. These sink- holes originated from the washing of the loess caprock into AREA OF STUDY karst conduits that were present in the Upper Jurassic bed- rock (Gradziñski, 1962; Gradziñski and Bary³a, 2005). The Kraków Upland is located in the area of the Sile- The group of Upper Jurassic tors exposed in the nature sian–Kraków Homocline. Its southern part is cut by numer- preserve is characterised by numerous rectilinear passages ous tectonic horsts and grabens (Fig. 1), resulting mostly (‘corridors’), several metres wide and with vertical rock 358 J. MATYSZKIEWICZ & A. KOCHMAN walls towering on either side (Fig. 2), formed when joint fractures were pulled apart by mass movements (Gradziñski and Bary³a, 2005). In the upper part of the limestone com- plex, one can observe particularly spectacular corridors with vertical walls, composed of pseudonodular limestones. Typical features of the tors are basal niches with overhang- ing ‘eaves’, presumably the effects of karstification of the pseudonodular limestones in conjunction with other weath- ering processes (Gradziñski and Bary³a, 2005). The Upper Jurassic strata of the Mników area attain a maximum thickness of about 130 m, whereas those in the Zimny Dó³ Valley are only 50–80 m thick (Gradziñski and Bary³a, 2005). The exposed limestones (Fig. 3) belong to the Transversarium-Bifurcatus ammonite zones (Matysz- kiewicz, 1994), corresponding to the middle/upper Oxfor- dian break (cf. Matyja and Wierzbowski, 2004). In the na- ture reserve, the Upper Jurassic limestone complex is about 40 m thick. In the eastern part of the reserve, the lower por- tion of the complex is dominated by a massive facies with local lenses of pseudonodular limestones. Pseudonodular limestones dominate in the western part of the reserve, in the upper part of the stratigraphic sequen- ce, above an elevation of 325 m a.s.l. (Fig. 2). Here, hori- zontal layers of pseudonodular limestones, several metres thick, rest upon massive limestones; horizons, nest-like bodies and lenses of pseudonodular limestones are enclosed within the massive facies. TERMINOLOGY Prior to the petrographic characterisation of the
Recommended publications
  • GEO 2008 Conference Abstracts, Bahrain GEO 2008 Conference Abstracts
    GEO 2008 conference abstracts, Bahrain GEO 2008 Conference Abstracts he abstracts of the GEO 2008 Conference presentations (3-5 March 2008, Bahrain) are published in Talphabetical order based on the last name of the first author. Only those abstracts that were accepted by the GEO 2008 Program Committee are published here, and were subsequently edited by GeoArabia Editors and proof-read by the corresponding author. Several names of companies and institutions to which presenters are affiliated have been abbreviated (see page 262). For convenience, all subsidiary companies are listed as the parent company. (#117804) Sandstone-body geometry, facies existing data sets and improve exploration decision architecture and depositional model of making. The results of a recent 3-D seismic reprocessing Ordovician Barik Sandstone, Oman effort over approximately 1,800 square km of data from the Mediterranean Sea has brought renewed interest in Iftikhar A. Abbasi (Sultan Qaboos University, Oman) deep, pre-Messinian structures. Historically, the reservoir and Abdulrahman Al-Harthy (Sultan Qaboos targets in the southern Mediterranean Sea have been the University, Oman <[email protected]>) Pliocene-Pleistocene and Messinian/Pre-Messinian gas sands. These are readily identifiable as anomalousbright The Lower Paleozoic siliciclastics sediments of the amplitudes on the seismic data. The key to enhancing the Haima Supergroup in the Al-Haushi-Huqf area of cen- deeper structure is multiple and noise attenuation. The tral Oman are subdivided into a number of formations Miocene and older targets are overlain by a Messinian- and members based on lithological characteristics of aged, structurally complex anhydrite layer, the Rosetta various rock sequences.
    [Show full text]
  • Deformation Mechanisms, Rheology and Tectonics Geological Society Special Publications Series Editor J
    Deformation Mechanisms, Rheology and Tectonics Geological Society Special Publications Series Editor J. BROOKS J/iLl THIS VOLUME IS DEDICATED TO THE WORK OF HENDRIK JAN ZWART GEOLOGICAL SOCIETY SPECIAL PUBLICATION NO. 54 Deformation Mechanisms, Rheology and Tectonics EDITED BY R. J. KNIPE Department of Earth Sciences Leeds University UK & E. H. RUTTER Department of Geology Manchester University UK ASSISTED BY S. M. AGAR R. D. LAW Department of Earth Sciences Department of Geological Sciences Leeds University Virginia University UK USA D. J. PRIOR R. L. M. VISSERS Department of Earth Sciences Institute of Earth Sciences Liverpool University University of Utrceht UK Netherlands 1990 Published by The Geological Society London THE GEOLOGICAL SOCIETY The Geological Society of London was founded in 1807 for the purposes of 'investigating the mineral structures of the earth'. It received its Royal Charter in 1825. The Society promotes all aspects of geological science by means of meetings, speeiat lectures and courses, discussions, specialist groups, publications and library services. It is expected that candidates for Fellowship will be graduates in geology or another earth science, or have equivalent qualifications or experience. Alt Fellows are entitled to receive for their subscription one of the Society's three journals: The Quarterly Journal of Engineering Geology, the Journal of the Geological Society or Marine and Petroleum Geology. On payment of an additional sum on the annual subscription, members may obtain copies of another journal. Membership of the specialist groups is open to all Fellows without additional charge. Enquiries concerning Fellowship of the Society and membership of the specialist groups should be directed to the Executive Secretary, The Geological Society, Burlington House, Piccadilly, London W1V 0JU.
    [Show full text]
  • Mechanical Stratigraphic Controls on Natural Fracture Spacing and Penetration
    Journal of Structural Geology 95 (2017) 160e170 Contents lists available at ScienceDirect Journal of Structural Geology journal homepage: www.elsevier.com/locate/jsg Mechanical stratigraphic controls on natural fracture spacing and penetration * Ronald N. McGinnis a, , David A. Ferrill a, Alan P. Morris a, Kevin J. Smart a, Daniel Lehrmann b a Department of Earth, Material, and Planetary Sciences, Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238-5166, USA b Geoscience Department, Trinity University, One Trinity Place, San Antonio, TX 78212, USA article info abstract Article history: Fine-grained low permeability sedimentary rocks, such as shale and mudrock, have drawn attention as Received 20 July 2016 unconventional hydrocarbon reservoirs. Fracturing e both natural and induced e is extremely important Received in revised form for increasing permeability in otherwise low-permeability rock. We analyze natural extension fracture 21 December 2016 networks within a complete measured outcrop section of the Ernst Member of the Boquillas Formation Accepted 7 January 2017 in Big Bend National Park, west Texas. Results of bed-center, dip-parallel scanline surveys demonstrate Available online 8 January 2017 nearly identical fracture strikes and slight variation in dip between mudrock, chalk, and limestone beds. Fracture spacing tends to increase proportional to bed thickness in limestone and chalk beds; however, Keywords: Mechanical stratigraphy dramatic differences in fracture spacing are observed in mudrock. A direct relationship is observed be- Natural fractures tween fracture spacing/thickness ratio and rock competence. Vertical fracture penetrations measured Fracture spacing from the middle of chalk and limestone beds generally extend to and often beyond bed boundaries into Fracture penetration the vertically adjacent mudrock beds.
    [Show full text]
  • The Role of Pressure Solution Seam and Joint Assemblages In
    THE ROLE OF PRESSURE SOLUTION SEAM AND JOINT ASSEMBLAGES IN THE FORMATION OF STRIKE-SLIP AND THRUST FAULTS IN A COMPRESSIVE TECTONIC SETTING; THE VARISCAN OF SOUTHWESTERN IRELAND Filippo Nenna and Atilla Aydin Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305 e-mail: [email protected] scale such as strike-slip faults and thrust-cored folds in Abstract various stages of their development. In this study we focus on the initiation and development of strike-slip The Ross Sandstone in County Clare, Ireland, was faults by shearing of the initial JVs and PSSs and deformed by an approximately north-south compression formation of thrust faults by exploiting weak shale during the end-Carboniferous Variscan orogeny. horizons and the strike-parallel PSSs in the adjacent Orthogonal sets of fundamental structures form the sandstone intervals. initial assemblage; mutually abutting arrays of 170˚ Development of faults from shearing of initial oriented set 1 joints/veins (JVs) and approximately 75˚ fundamental structural elements with either opening or pressure solution seams (PSSs) that formed under the closing modes in a wide range of structural settings has same stress conditions. Orientations of set 2 (splay) JVs been extensively reported. Segall and Pollard (1983), and PSSs suggest a clockwise remote stress rotation of Martel and Pollard (1989) and Martel (1990) have about 35˚ responsible for the contemporaneous described strike-slip faults formed by shearing of shearing of the set 1 arrays. Prominent strike-slip faults thermal fractures in granitic rocks. Myers and Aydin are sub-parallel to set 1 JVs and form by the linkage of (2004) and Flodin and Aydin (2004) reported strike-slip en-echelon segments with broad damage zones faulting formed by shearing of joints formed by an responsible for strike-slip offsets of hundreds of metres.
    [Show full text]
  • Sedimentary Stylolite Networks and Connectivity in Limestone
    Sedimentary stylolite networks and connectivity in Limestone: Large-scale field observations and implications for structure evolution Leehee Laronne Ben-Itzhak, Einat Aharonov, Ziv Karcz, Maor Kaduri, Renaud Toussaint To cite this version: Leehee Laronne Ben-Itzhak, Einat Aharonov, Ziv Karcz, Maor Kaduri, Renaud Toussaint. Sed- imentary stylolite networks and connectivity in Limestone: Large-scale field observations and implications for structure evolution. Journal of Structural Geology, Elsevier, 2014, pp.online first. <10.1016/j.jsg.2014.02.010>. <hal-00961075v2> HAL Id: hal-00961075 https://hal.archives-ouvertes.fr/hal-00961075v2 Submitted on 19 Mar 2014 HAL is a multi-disciplinary open access L'archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destin´eeau d´ep^otet `ala diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publi´esou non, lished or not. The documents may come from ´emanant des ´etablissements d'enseignement et de teaching and research institutions in France or recherche fran¸caisou ´etrangers,des laboratoires abroad, or from public or private research centers. publics ou priv´es. 1 2 Sedimentary stylolite networks and connectivity in 3 Limestone: Large-scale field observations and 4 implications for structure evolution 5 6 Laronne Ben-Itzhak L.1, Aharonov E.1, Karcz Z.2,*, 7 Kaduri M.1,** and Toussaint R.3,4 8 9 1 Institute of Earth Sciences, The Hebrew University, Jerusalem, 91904, Israel 10 2 ExxonMobil Upstream Research Company, Houston TX, 77027, U.S.A 11 3 Institut de Physique du Globe de Strasbourg, University of Strasbourg/EOST, CNRS, 5 rue 12 Descartes, F-67084 Strasbourg Cedex, France.
    [Show full text]
  • Structural Geology
    2 STRUCTURAL GEOLOGY Conventional Map A map is a proportionate representation of an area/structure. The study of maps is known as cartography and the experts are known as cartographers. The maps were first prepared by people of Sumerian civilization by using clay lens. The characteristic elements of a map are scale (ratio of map distance to field distance and can be represented in three ways—statement method, e.g., 1 cm = 0.5 km, representative fraction method, e.g., 1:50,000 and graphical method in the form of a figure), direction, symbol and colour. On the basis of scale, maps are of two types: large-scale map (map gives more information pertaining to a smaller area, e.g., village map: 1:3956) and small: scale map (map gives less information pertaining to a larger area, e.g., world atlas: 1:100 km). Topographic Maps / Toposheet A toposheet is a map representing topography of an area. It is prepared by the Survey of India, Dehradun. Here, a three-dimensional feature is represented on a two-dimensional map and the information is mainly represented by contours. The contours/isohypses are lines connecting points of same elevation with respect to mean sea level (msl). The index contours are the contours representing 100’s/multiples of 100’s drawn with thick lines. The contour interval is usually 20 m. The contours never intersect each other and are not parallel. The characteristic elements of a toposheet are scale, colour, symbol and direction. The various layers which can be prepared from a toposheet are structural elements like fault and lineaments, cropping pattern, land use/land cover, groundwater abstruction structures, drainage density, drainage divide, elongation ratio, circularity ratio, drainage frequency, natural vegetation, rock types, landform units, infrastructural facilities, drainage and waterbodies, drainage number, drainage pattern, drainage length, relief/slope, stream order, sinuosity index and infiltration number.
    [Show full text]
  • Part 629 – Glossary of Landform and Geologic Terms
    Title 430 – National Soil Survey Handbook Part 629 – Glossary of Landform and Geologic Terms Subpart A – General Information 629.0 Definition and Purpose This glossary provides the NCSS soil survey program, soil scientists, and natural resource specialists with landform, geologic, and related terms and their definitions to— (1) Improve soil landscape description with a standard, single source landform and geologic glossary. (2) Enhance geomorphic content and clarity of soil map unit descriptions by use of accurate, defined terms. (3) Establish consistent geomorphic term usage in soil science and the National Cooperative Soil Survey (NCSS). (4) Provide standard geomorphic definitions for databases and soil survey technical publications. (5) Train soil scientists and related professionals in soils as landscape and geomorphic entities. 629.1 Responsibilities This glossary serves as the official NCSS reference for landform, geologic, and related terms. The staff of the National Soil Survey Center, located in Lincoln, NE, is responsible for maintaining and updating this glossary. Soil Science Division staff and NCSS participants are encouraged to propose additions and changes to the glossary for use in pedon descriptions, soil map unit descriptions, and soil survey publications. The Glossary of Geology (GG, 2005) serves as a major source for many glossary terms. The American Geologic Institute (AGI) granted the USDA Natural Resources Conservation Service (formerly the Soil Conservation Service) permission (in letters dated September 11, 1985, and September 22, 1993) to use existing definitions. Sources of, and modifications to, original definitions are explained immediately below. 629.2 Definitions A. Reference Codes Sources from which definitions were taken, whole or in part, are identified by a code (e.g., GG) following each definition.
    [Show full text]
  • Stress and Fluid Control on De Collement Within Competent Limestone
    Journal of Structural Geology 22 (2000) 349±371 www.elsevier.nl/locate/jstrugeo Stress and ¯uid control on de collement within competent limestone Antonio Teixell a,*, David W. Durney b, Maria-Luisa Arboleya a aDepartament de Geologia, Universitat AutoÁnoma de Barcelona, 08193 Bellaterra, Spain bDepartment of Earth and Planetary Sciences, Macquarie University, Sydney, NSW 2109, Australia Received 5 October 1998; accepted 23 September 1999 Abstract The Larra thrust of the Pyrenees is a bedding-parallel de collement located within a competent limestone unit. It forms the ¯oor of a thrust system of hectometric-scale imbrications developed beneath a synorogenic basin. The fault rock at the de collement is a dense stack of mainly bedding-parallel calcite veins with variable internal deformation by twinning and recrystallization. Veins developed as extension fractures parallel to a horizontal maximum compressive stress, cemented by cavity-type crystals. Conditions during vein formation are interpreted in terms of a compressional model where crack-arrays develop at applied stresses approaching the shear strength of the rock and at ¯uid pressures equal to or less than the overburden pressure. The cracks developed in response to high dierential stress, which was channelled in the strong limestone, and high ¯uid pressure in or below the thrust plane. Ductile deformation, although conspicuous, cannot account for the kilometric displacement of the thrust, which was mostly accommodated by slip on water sills constituted by open cracks. A model of cyclic dierential brittle contraction, stress reorientation, slip and ductile relaxation at a rheological step in the limestone is proposed as a mechanism for episodic de collement movement.
    [Show full text]
  • Stylolites: Characteristics and Origin
    • STYLOLITES: CHARACTERISTICS AND ORIGIN Joseph M. Montello A senior thesis submitted to fulfill the requirements for the degree of B.S. in Geology and Mineralogy • Winter Quarter, 1984 The Ohio State University ~2.~r·Thesis Advisor Department of Geology and Mineralogy Abstract • Stylolites are alternating interpenetrating columns of stone that form irregular interlocking partings or sutures in rock strata. They are most common along bedding planes of limestone but some are oblique or even perpendicular to bedding . Although the vast majority of stylolites occur in calcareous rocks, stylolites have been found in sandstone, quartzite and gypsum. The word "stylolite" refers to each individual column of stone. A cross section of a group of stylolites parallel to their length presents a rough, jagged line called a "stylolite seam" that resembles the sutures of a human skull. Stylolites always have a dark colored "clay" cap at the ends of the columns. The sides of the columns are typically discolored with a thin film of clay and show parallel flutings or striations that parallel their length. The shapes of individual stylolites vary greatly from broad flat­ • topped columns to pointed, jagged and tapering forms. After much controversy concerning the origin of stylolites, it is generally believed that they form by a process of chemical solution under pressure in lithified rock along some crack or seam. The interteething is produced because of differential solubilities and pressures within the rock unit. The clay cap on the stylolites is the non-soluble residue of the dissolved rock. Stylolites are only one of the possible end products in the spectrum of limestone responses to stress.
    [Show full text]
  • Stylolite Compaction and Stress Models
    Geophysical Research Abstracts, Vol. 11, EGU2009-1720, 2009 EGU General Assembly 2009 © Author(s) 2009 Stylolite compaction and stress models D. Koehn (1), M. Ebner (1), F. Renard (2), and R. Toussaint (3) (1) University of Mainz, Department of Geology, Mainz, Germany ([email protected]), (2) LGIT-CNRS-Observatoire, University of Grenoble, France, (3) Institut de Physique du Globe de Strasbourg, University of Strasbourg, France Stylolites are rough dissolution seams that develop during pressure solution in the Earth’s crust. Especially in limestone quarries they exhibit a spectacular roughness with spikes and large columns. They are visible as dark lines of residual clays and other non-dissolvable components in the white limestone. The roughening phenomena seems to be universal since stylolites can also be found in quarzites, mylonites and all kinds of rocks that undergo pressure solution. The genesis of stylolites is not well understood even though they have been used to estimate compaction and to determine the direction of the main compressive stress. We have developed a numerical model to study the dynamic development of the roughness and its dependence on stress. Based on the model we present estimates of finite strain and depth of burial. The numerical stylolites are studied in two ways: the temporal evolution of the roughness on one hand and the fractal characteristics of the roughness on the other hand. In addition we vary the noise in the model and illustrate the importance of the grain size on the roughening process. Surface energies are dominant for small wavelengths and the initial stylolite growth is non-linear and as slow as a diffusive process.
    [Show full text]
  • Structural Evolution of the Northernmost Andes, Colombia
    Structural Evolution of the Northernmost Andes, Colombia GEOLOGICAL SURVEY PROFESSIONAL PAPER 846 Prepared in coopeTation ·with the lnstituto Nacional de Investigaciones Geologico-MineTas under the auspices of the Government of Colombia and the Agency for International Development) United States DepaTtment of State Structural Evolution of the Northernmost Andes, Colombia By EARL M. IRVING GEOLOGICAL SURVEY PROFESSIONAL PAPER 846 Prepared in cooperation ·with the lnstituto Nacional de Investigaciones Geologico-Min eras under the auspices of the Government of Colombia and the Agency for International Development) United States Department of State An interpretation of the geologic history of a complex mountain system UNITED STATES GOVERNlVIENT PRINTING OFFICE, vVASHINGTON 1975 UNITED STATES DEPARTMENT OF THE INTERIOR ROGERS C. B. MORTON, Secretary GEOLOGICAL SURVEY V. E. McKelvey, Director Library of Congress Cataloging in Publication Data Irving, Earl Montgomery, 1911- Structural evolution of the northernmost Andes, Columbia. (Geological Survey professional paper ; 846) Bibliography: p Includes index. Supt. of Docs. no.: I 19.16:846 1. Geology-Colombia. 2. Geosynclines----Colombia. I. Instituto Nacional de Investigaciones Geologico­ Mineras.. II. Title. III. Series: United States. Geological Survey. Professional paper ; 846. QE239.175 558.61 74-600149 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402- Price $1.30 (paper cover) Stock Number 2401-02553 CONTENTS Page Pasre Abstract ----------------------------------------
    [Show full text]
  • Observations on Normal-Fault Scarp Morphology and Fault System Evolution of the Bishop Tuff in the Volcanic Tableland, Owens Valley, California, U.S.A
    Observations on normal-fault scarp morphology and fault system evolution of the Bishop Tuff in the Volcanic Tableland, Owens Valley, California, U.S.A. David A. Ferrill, Alan P. Morris, Ronald N. McGinnis, Kevin J. Smart, Morgan J Watson-Morris, and Sarah S. Wigginton DEPARTMENT OF EARTH, MATERIAL, AND PLANETARY SCIENCES, SOUTHWEST RESEARCH INSTITUTE®, 6220 CULEBRA ROAD, SAN ANTONIO, TEXAS 78238, USA ABSTRACT Mapping of normal faults cutting the Bishop Tuff in the Volcanic Tableland, northern Owens Valley, California, using side-looking airborne radar data, low-altitude aerial photographs, airborne light detection and ranging (LiDAR) data, and standard field mapping yields insights into fault scarp development, fault system evolution, and timing. Fault zones are characterized by multiple linked fault segments, tilting of the welded ignimbrite surface, dilation of polygonal cooling joints, and toppling of joint-bounded blocks. Maximum fault zone width is governed by (i) lateral spacing of cooperating fault segments and (ii) widths of fault tip monoclines. Large-displacement faults interact over larger rock volumes than small-displacement faults and generate larger relay ramps, which, when breached, form the widest portions of fault zones. Locally intense faulting within a breached relay ramp results from a combination of distributed east-west extension, and within- ramp bending and stretching to accommodate displacement gradients on bounding faults. One prominent fluvial channel is offset by both east- and west-dipping normal faults such that the channel is no longer in an active flowing configuration, indicating that channel incision began before development of significant fault-related geomorphic features. The channel thalweg is “hanging” with respect to modern (Q1) and previous (Q2) Owens River terraces, is incised through the pre-Tahoe age terrace level (Q4, 131–463 ka), and is at grade with the Tahoe age (Q3, 53–119 ka) terrace.
    [Show full text]