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TO BE DONE in BOOK} A
CLASS6 DATE: 16.05.2020 CHAPTER 2. LANDFORMS EXERCISE WITH QUESTION ANSWERS AND MAP WORK. 1. TICK THE RIGHT OPTION {TO BE DONE IN BOOK} a. Aravallis. b. Intermontane plateau. c. Faulting. d. Deposition. 2. FILL IN THE BLANKS {TO BE DONE IN BOOK} a. Pointed. b. Minerals. c. Fault zone. d. Old fold. 3. Differentiate between: {TO BE DONE IN NOTEBOOK} a. Old Fold Mountain Young Fold Mountain These mountains have been subjected to the They are newly formed and having forces of denudation for a long geological heights higher than old fold mountain. period. They are much lower with rounded peaks They have pointed peaks, steeper and and gentle slopes. deeper slopes. Eg: Aravalli in India. Eg: The Himalayas in India. b. Rift Valley Block mountain The lowland mass remaining after the The uplifted land mass remaining after faulting are known as Rift valley. the faulting are known as Block mountains It is bordered by fault zones and separated Block mountains are steep sided and flat by land masses. topped. Eg: Great Rift Valley of Africa. Eg: Vindhyas in India. c. Erosional Plains Depositional Plains This type of plains are formed as result of It is formed as a result of deposition of erosion and weathering. sediments. These plains have been flattened by the These plains are made by depositing the erosion of soil and rocks away from a soil and rocks on a lower surface. higher feature. Eg:- Upper Mississippi valley of USA. Eg:- The Indo-Gangetic Plains in India. d. Intermontane Plateaus Piedmont Plateaus They are the highest and the most extensive They are relatively low rolling hills with type. -
Poster Final
Evidence for polyphase deformation in the mylonitic zones bounding the Chester and Athens Domes, in southeastern Vermont, from 40Ar/39Ar geochronology Schnalzer, K., Webb, L., McCarthy, K., University of Vermont Department of Geology, Burlington Vermont, USA CLM 40 39 Sample Mineral Assemblage Metamorphic Facies Abstract Microstructure and Ar/ Ar Geochronology 18CD08A Quartz, Muscovite, Biotite, Feldspar, Epidote Upper Greenschist to Lower Amphibolite The Chester and Athens Domes are a composite mantled gneiss QC Twelve samples were collected during the fall of 2018 from the shear zones bounding the Chester and Athens Domes for 18CD08B Quartz, Biotite, Feldspar, Amphibole Amphibolite Facies 18CD08C Quartz, Muscovite, Biotite, Feldspar, Epidote Upper Greenschist to Lower Amphibolite dome in southeast Vermont. While debate persists regarding Me 40 39 microstructural analysis and Ar/ Ar age dating. These samples were divided between two transects, one in the northeastern 18CD08D Quartz, Muscovite, Biotite, Feldspar, Garnet Upper Greenschist to Lower Amphibolite the mechanisms of dome formation, most workers consider the VT NH section of the Chester dome and the second in the southern section of the Athens dome. These samples were analyzed by X-ray 18CD08E Quartz, Muscovite Greenschist Facies domes to have formed during the Acadian Orogeny. This study diraction in the fall of 2018. Oriented, orthogonal thin sections were also prepared for each of the twelve samples. The thin sec- 18CD09A Quartz, Amphibole Amphib olite Facies 40 CVGT integrates the results of Ar/Ar step-heating of single mineral NY tions named with an “X” were cut parallel to the stretching lineation (X) and normal to the foliation (Z) whereas the thin sections 18CD09B Quartz, Biotite, Feldspar, Amphibole, Muscovite Amphibolite Facies grains, or small multigrain aliquots, with data from microstruc- 18CD09C Quartz, Amphibole, Feldspar Amphibolite Facies named with a “Y” have been cut perpendicular to the ‘X-Z’ thin section. -
Tectonic Imbrication and Foredeep Development in the Penokean
Tectonic Imbrication and Foredeep Development in the Penokean Orogen, East-Central Minnesota An Interpretation Based on Regional Geophysics and the Results of Test-Drilling The Penokean Orogeny in Minnesota and Upper Michigan A Comparison of Structural Geology U.S. GEOLOGICAL SURVEY BULLETIN 1904-C, D AVAILABILITY OF BOOKS AND MAPS OF THE U.S. GEOLOGICAL SURVEY Instructions on ordering publications of the U.S. Geological Survey, along with prices of the last offerings, are given in the cur rent-year issues of the monthly catalog "New Publications of the U.S. Geological Survey." Prices of available U.S. Geological Sur vey publications released prior to the current year are listed in the most recent annual "Price and Availability List." Publications that are listed in various U.S. Geological Survey catalogs (see back inside cover) but not listed in the most recent annual "Price and Availability List" are no longer available. Prices of reports released to the open files are given in the listing "U.S. Geological Survey Open-File Reports," updated month ly, which is for sale in microfiche from the U.S. Geological Survey, Books and Open-File Reports Section, Federal Center, Box 25425, Denver, CO 80225. Reports released through the NTIS may be obtained by writing to the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161; please include NTIS report number with inquiry. Order U.S. Geological Survey publications by mail or over the counter from the offices given below. BY MAIL OVER THE COUNTER Books Books Professional Papers, Bulletins, Water-Supply Papers, Techniques of Water-Resources Investigations, Circulars, publications of general in Books of the U.S. -
Strike and Dip Refer to the Orientation Or Attitude of a Geologic Feature. The
Name__________________________________ 89.325 – Geology for Engineers Faults, Folds, Outcrop Patterns and Geologic Maps I. Properties of Earth Materials When rocks are subjected to differential stress the resulting build-up in strain can cause deformation. Depending on the material properties the result can either be elastic deformation which can ultimately lead to the breaking of the rock material (faults) or ductile deformation which can lead to the development of folds. In this exercise we will look at the various types of deformation and how geologists use geologic maps to understand this deformation. II. Strike and Dip Strike and dip refer to the orientation or attitude of a geologic feature. The strike line of a bed, fault, or other planar feature, is a line representing the intersection of that feature with a horizontal plane. On a geologic map, this is represented with a short straight line segment oriented parallel to the strike line. Strike (or strike angle) can be given as either a quadrant compass bearing of the strike line (N25°E for example) or in terms of east or west of true north or south, a single three digit number representing the azimuth, where the lower number is usually given (where the example of N25°E would simply be 025), or the azimuth number followed by the degree sign (example of N25°E would be 025°). The dip gives the steepest angle of descent of a tilted bed or feature relative to a horizontal plane, and is given by the number (0°-90°) as well as a letter (N, S, E, W) with rough direction in which the bed is dipping. -
Monoclinal Flexure of an Orogenic Plateau Margin During Subduction, South Turkey
Non-peer reviewed preprint submitted to EarthArXiv Monoclinal flexure of an orogenic plateau margin during subduction, south Turkey Running title: Monoclinal flexure plateau margin David Fernández-Blanco1, Giovanni Bertotti2, Ali Aksu3 and Jeremy Hall3 1Tectonics and Structural Geology Department, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, the Netherlands [email protected] 2Department of Geotechnology, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Stevinweg 1, 2628CN, Delft, the Netherlands 3 Department of Earth Sciences, Centre for Earth Resources Research, Memorial University of Newfoundland, St. John's, Newfoundland, Canada A1B 3X5 Non-peer reviewed preprint submitted to EarthArXiv Abstract Geologic evidence across orogenic plateau margins helps to discriminate the relative contributions of orogenic, epeirogenic and/or climatic processes leading to growth and maintenance of orogenic plateaus and plateau margins. Here, we discuss the mode of formation of the southern margin of the Central Anatolian Plateau (SCAP), and evaluate its time of formation, using fieldwork in the onshore and seismic reflection data in the offshore. In the onshore, uplifted Miocene rocks in a dip-slope topography show monocline flexure over >100 km, few-km asymmetric folds verging south, and outcrop- scale syn-sedimentary reverse faults. On the Turkish shelf, vertical faults transect the basal latest Messinian of a ~10 km fold where on-structure syntectonic wedges and synsedimentary unconformities indicate pre-Pliocene uplift and erosion followed by Pliocene and younger deformation. Collectively, Miocene rocks delineate a flexural monocline at plateau margin scale, expressed along our on-offshore sections as a kink- band fold with a steep flank ~20–25 km long. -
Sedimentary Record of Cretaceous And
SEDIMENT AR Y RECORD OF CRETACEOUS AND TER TIAR Y SALT MOVEMENT, EAST TEXAS BASIN: TIMES, RATES, AND LUMES OF SALT FLOW, IMPLICATIONS TO NUCLEAR-WA TE ISOLATION AND PETROLEUM EXPLO ATION by Steven J. Seni and M. P. A. ackson This work was supported by U.S. Depart ent of Energy and funded under Contract No. DE-AC 7-80ET46617 CONTENTS ABSTRACT . • 00 INTRODUCTION. • 00 Data Base. • 00 Early History of Basin Formation and Infilling • 00 Geometry of Salt Structures • 00 EVOLUTIONARY STAGES OF DOME GROWTH. • 00 Pillow Stage . • 00 Geometry of Overlying Strata . • 00 Geometry of Surrounding Strata • 00 Depositional Facies and Lithostratigraph • 00 Diapir Stage • • 00 Geometry of Surrounding Strata • 00 Depositional Facies and Lithostratigraph • 00 Post-Diapir Stage • 00 Geometry of Surrounding Strata • 00 Depositional Facies and Lithostratigraphy • 00 Holocene Analogues. • 00 Discussion • 00 Significance to Subtle Petroleum Traps • 00 PATTERNS OF SALT MOVEMENT IN TIME AND SPAC • 00 Group 1: Pre-Glen Rose Subgroup (pre-112 Ma) - Periphery of Diapir Province • • 00 Group 2: Glen Rose Subgroup to Washita Group 112 to 98 Ma)- Basin Axis • 00 Group 3: Post-Austin Group (86 to 56 Ma) -- Per phery of Diapir Province • • 00 Initiation and Acceleration of Salt Flow • • 00 Overview of Dome History • • 00 RATES OF SALT MOVEMENT AND DOME GROWTH • • 00 Assumptions • • 00 Proven Propositions. • 00 Unproven Propositions • 00 Incorrect Propositions • • 00 Distinguishing Between Syndepositional and Post-D positional Thickness Variations. • 00 The Problem • • 00 Structural Evidence • • 00 Sedimentological Evidence • • 00 Methodology • • 00 Distinguishing Between Regional and Salt-Re ated Thickness Variations. • 00 Volume of Salt Mobilized and Estimates of S t Loss • 00 Rates of Dome Growth • • 00 Net Rates of Pillow Growth • 00 Net Rates of Diapir Growth • 00 Gross Rates of Diapir Growth • • 00 Growth Rates and Strain Rates • 00 IMPLICA TIONS TO WASTE ISOLATION • • 00 CONCLUSIONS • • 00 ACKNOWLEDGMENTS • • 00 REFERENCES • 00 APPENDICES • 00 Figures 1. -
Influences of Surface Processes on Fold Growth During 3D Detachment
PUBLICATIONS Geochemistry, Geophysics, Geosystems RESEARCH ARTICLE Influences of surface processes on fold growth during 3-D 10.1002/2014GC005450 detachment folding Key Point: M. Collignon1, B. J. P. Kaus2, D. A. May3, and N. Fernandez2 Influences of surface processes on the fold pattern in fold-and-thrust 1Geological Institute, ETH Zurich, Zurich, Switzerland, 2Institut fur€ Geowissenschaften, Johannes Gutenberg-Universit€at, belts Mainz, Germany, 3Institute of Geophysics, ETH Zurich, Zurich, Switzerland Correspondence to: M. Collignon, Abstract In order to understand the interactions between surface processes and multilayer folding sys- [email protected] tems, we here present fully coupled three-dimensional numerical simulations. The mechanical model repre- sents a sedimentary cover with internal weak layers, detached over a much weaker basal layer representing Citation: salt or evaporites. Applying compression in one direction results in a series of three-dimensional buckle folds, Collignon, M., B. J. P. Kaus, D. A. May, and N. Fernandez (2014), Influences of of which the topographic expression consists of anticlines and synclines. This topography is modified through surface processes on fold growth time by mass redistribution, which is achieved by a combination of fluvial and hillslope erosion, as well as during 3-D detachment folding, deposition, and which can in return influence the subsequent deformation. Model results show that surface Geochem. Geophys. Geosyst., 15, doi:10.1002/2014GC005450. processes do not have a significant influence on folding patterns and aspect ratio of the folds. Nevertheless, erosion reduces the amount of shortening required to initiate folding and increases the exhumation rates. Received 9 JUN 2014 Increased sedimentation in the synclines contributes to this effect by amplifying the fold growth rate by grav- Accepted 29 JUL 2014 ity. -
Tectonic Evolution of Structures in Southern Sindh Monocline, Indus Basin, Pakistan Formed in Multi-Extensional Tectonic Episodes of Indian Plate
Tectonic Evolution of Structures in Southern Sindh Monocline, Indus Basin, Pakistan Formed in Multi-Extensional Tectonic Episodes of Indian Plate Sarfraz Hussain Solangi, Shabeer Ahmed, Muhammad Akram Qureshi, Mohammad Shahid, Uzair Hamid Awan Universityof Sindh, Pakistan Summary There are number of structures and structural styles found in extensional tectonic settings of the world but the evolution of these structuresis still needful and a big challenge as well. Evolution of structures in extensional settings have been studied by Yuan Li et al., (2016)and many other reserachers on different extensional basins of the world. Sindh Monocline lies on the western corner of Indian Plate and the tectonic history of Indian plate has been well described by Chatterjee et al., (2013) while tectonic history of Sindh Monocline has been studied by Zaigham, and Mallick, (2000), Chatterjee et al., (2013) (Fig.1). The aim of this study is the evolution of structures in the subsurface of Southern Sindh Monocline, Pakistan using the seismic data interpretation and faltenning of horizons approach. Jamaluddin et al., (2015) and others have also testified such approach. Southern Sindh Monocline is charaterized and experienced by different tectonic episodes of Indian plate while rifting from Gondwanaland, rifting from other plates at different geological times and to its collision with the Asia. Basic structures with in study area are classified into nine types whilethe structural styles have been classified into six types as horst and grabens,dominos,crotch,synthetic -
Mountains Block Mountains
Mountains Block Mountains • Block mountains are created when large areas or blocks of earth are broken and displaced vertically. • The uplifted blocks are termed as horsts and the lowered blocks are called graben. • Block mountains are also called fault block mountains since they are formed due to faulting as a result of tensile and compressive forces. • Block mountains are surrounded by faults on either side of rift valleys or grabens. • The Great African Rift Valley (valley floor is graben), The Rhine Valley and the Vosges mountain in Europe are examples. Compression and Tension • When the earth’s crust bends folding occurs, but when it cracks, faulting takes place. • The faulted edges are very steep, e.g. the Vosges and Black Forest of the Rhineland. • Tension may also cause the central portion to be let down between two adjacent fault blocks forming a graben or rift valley, which will have steep walls. • The East African Rift Valley system is the best example. It is 3,000 miles long, stretching from East Africa through the Red Sea to Syria. • Compressional forces set up by earth movements may produce a thrust or reverse fault and shorten the crust. A block may be raised or lowered in relation to surrounding areas. • In general large-scale block mountains and rift valleys are due to tension rather than compression. • The faults may occur in series and be further complicated by tilting and other irregularities. • Denudation through the ages modifies faulted landforms. • Block mountains may originate when the middle block moves downward and becomes a rift valley while the surrounding blocks stand higher as block mountains. -
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. -
Geology and Stratigraphy Column
Capitol Reef National Park National Park Service U.S. Department of the Interior Geology “Geology knows no such word as forever.” —Wallace Stegner Capitol Reef National Park’s geologic story reveals a nearly complete set of Mesozoic-era sedimentary layers. For 200 million years, rock layers formed at or near sea level. About 75-35 million years ago tectonic forces uplifted them, forming the Waterpocket Fold. Forces of erosion have been sculpting this spectacular landscape ever since. Deposition If you could travel in time and visit Capitol Visiting Capitol Reef 180 million years ago, Reef 245 million years ago, you would not when the Navajo Sandstone was deposited, recognize the landscape. Imagine a coastal you would have been surrounded by a giant park, with beaches and tidal flats; the water sand sea, the largest in Earth’s history. In this moves in and out gently, shaping ripple marks hot, dry climate, wind blew over sand dunes, in the wet sand. This is the environment creating large, sweeping crossbeds now in which the sediments of the Moenkopi preserved in the sandstone of Capitol Dome Formation were deposited. and Fern’s Nipple. Now jump ahead 20 million years, to 225 All the sedimentary rock layers were laid million years ago. The tidal flats are gone and down at or near sea level. Younger layers were the climate supports a tropical jungle, filled deposited on top of older layers. The Moenkopi with swamps, primitive trees, and giant ferns. is the oldest layer visible from the visitor center, The water is stagnant and a humid breeze with the younger Chinle Formation above it. -
The Central Zagros Fold-Thrust Bemt (Iran) : New Insights from Seismic Data Field Observation and Sandbox Modelling S
The Central Zagros fold-thrust bemt (Iran) : New insights from seismic data field observation and sandbox modelling S. Sherkati, J. Letouzey, Dominique Frizon de Lamotte To cite this version: S. Sherkati, J. Letouzey, Dominique Frizon de Lamotte. The Central Zagros fold-thrust bemt (Iran) : New insights from seismic data field observation and sandbox modelling. Tectonics, American Geo- physical Union (AGU), 2006, 25 (4), pp.TC4007. 10.1029/2004TC001766. hal-00069591 HAL Id: hal-00069591 https://hal.archives-ouvertes.fr/hal-00069591 Submitted on 29 May 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Copyright TECTONICS, VOL. 25, TC4007, doi:10.1029/2004TC001766, 2006 Central Zagros fold-thrust belt (Iran): New insights from seismic data, field observation, and sandbox modeling S. Sherkati,1 J. Letouzey,2 and D. Frizon de Lamotte3 Received 10 November 2004; revised 27 January 2006; accepted 29 March 2006; published 20 July 2006. [1] We present five generalized cross sections across levels are activated sequentially from deeper horizons the central Zagros fold-and-thrust belt (Iran). These to shallower ones. However, in one case (Gachsaran sections show that the fold geometry varies de´collement) a shallow de´collement is activated during significantly both horizontally and vertically.