Advanced Stress Analysis
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Geological and Seismic Evidence for the Tectonic Evolution of the NE Oman Continental Margin and Gulf of Oman GEOSPHERE, V
Research Paper GEOSPHERE Geological and seismic evidence for the tectonic evolution of the NE Oman continental margin and Gulf of Oman GEOSPHERE, v. 17, no. X Bruce Levell1, Michael Searle1, Adrian White1,*, Lauren Kedar1,†, Henk Droste1, and Mia Van Steenwinkel2 1Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK https://doi.org/10.1130/GES02376.1 2Locquetstraat 11, Hombeek, 2811, Belgium 15 figures ABSTRACT Arabian shelf or platform (Glennie et al., 1973, 1974; Searle, 2007). Restoration CORRESPONDENCE: [email protected] of the thrust sheets records several hundred kilometers of shortening in the Late Cretaceous obduction of the Semail ophiolite and underlying thrust Neo-Tethyan continental margin to slope (Sumeini complex), basin (Hawasina CITATION: Levell, B., Searle, M., White, A., Kedar, L., Droste, H., and Van Steenwinkel, M., 2021, Geological sheets of Neo-Tethyan oceanic sediments onto the submerged continental complex), and trench (Haybi complex) facies rocks during ophiolite emplace- and seismic evidence for the tectonic evolution of the margin of Oman involved thin-skinned SW-vergent thrusting above a thick ment (Searle, 1985, 2007; Cooper, 1988; Searle et al., 2004). The present-day NE Oman continental margin and Gulf of Oman: Geo- Guadalupian–Cenomanian shelf-carbonate sequence. A flexural foreland basin southwestward extent of the ophiolite and Hawasina complex thrust sheets is sphere, v. 17, no. X, p. 1– 22, https:// doi .org /10.1130 /GES02376.1. (Muti and Aruma Basin) developed due to the thrust loading. Newly available at least 150 km across the Arabian continental margin. The obduction, which seismic reflection data, tied to wells in the Gulf of Oman, suggest indirectly spanned the Cenomanian to Early Maastrichtian (ca 95–72 Ma; Searle et al., Science Editor: David E. -
Glacial Tectonics: a Deeper Perspective Robert M
Quaternary Science Reviews 19 (2000) 1391}1398 Glacial tectonics: a deeper perspective Robert M. Thorson* Department of Geology and Geophysics, University of Connecticut, 345 Mansxeld Road (U-45), Storrs, CT 06269, USA Abstract The upper 5}10 km of the lithosphere is sensitive to slight changes ((0.1 MPa) in local stress caused by di!erential loading, #uid #ow, the mechanical transfer of strain between faults, and viscoelastic relaxation in the aesthenosphere. Lithospheric stresses induced by mass and #uid transfers associated with Quaternary ice sheets a!ected the tectonic regimes of stable cratons and active plate margins. In the latter case, it is di$cult to di!erentiate glacially induced fault displacements from nonglacial ones, particularly if residual glacial stresses are considered. Glaciotectonics, a sub-subdiscipline within Quaternary geology is historically focussed on reconstructing past glacier regimes and, by de"nition, does not include these e!ects. The term `glacial tectonicsa is hereby suggested for investigations focussed on the past and continuing in#uences of ice sheets on contemporary tectonics. ( 2000 Elsevier Science Ltd. All rights reserved. 1. Introduction e!ects of glacial mass transfers is blurring the distinction between the study of tectonics, per se, and the study of Presently, there is a conceptual shift in the geosciences `glaciotectonicsa, which, historically, has been primarily away from increasing specialization, towards more inte- concerned with deformed glacial deposits. grative problems at global scales, a shift embodied by the In this paper I show how the physical coupling be- phrase `Earth System Sciencea (Kump et al., 1999). Si- tween glaciation and crustal deformation extends far multaneously, technologically driven advances in instru- beyond the decollement between ice and its substrate (i.e. -
"Preserve Analysis : Saddle Mountain"
PRESERVE ANALYSIS: SADDLE MOUNTAIN Pre pare d by PAUL B. ALABACK ROB ERT E. FRENKE L OREGON NATURAL AREA PRESERVES ADVISORY COMMITTEE to the STATE LAND BOARD Salem. Oregon October, 1978 NATURAL AREA PRESERVES ADVISORY COMMITTEE to the STATE LAND BOARD Robert Straub Nonna Paul us Governor Clay Myers Secretary of State State Treasurer Members Robert Frenkel (Chairman), Corvallis Bill Burley (Vice Chainnan), Siletz Charles Collins, Roseburg Bruce Nolf, Bend Patricia Harris, Eugene Jean L. Siddall, Lake Oswego Ex-Officio Members Bob Maben Wi 11 i am S. Phe 1ps Department of Fish and Wildlife State Forestry Department Peter Bond J. Morris Johnson State Parks and Recreation Branch State System of Higher Education PRESERVE ANALYSIS: SADDLE MOUNTAIN prepared by Paul B. Alaback and Robert E. Frenkel Oregon Natural Area Preserves Advisory Committee to the State Land Board Salem, Oregon October, 1978 ----------- ------- iii PREFACE The purpose of this preserve analysis is to assemble and document the significant natural values of Saddle Mountain State Park to aid in deciding whether to recommend the dedication of a portion of Saddle r10untain State Park as a natural area preserve within the Oregon System of I~atural Areas. Preserve management, agency agreements, and manage ment planning are therefore not a function of this document. Because of the outstanding assemblage of wildflowers, many of which are rare, Saddle r·1ountain has long been a mecca for· botanists. It was from Oregon's botanists that the Committee initially received its first documentation of the natural area values of Saddle Mountain. Several Committee members and others contributed to the report through survey and documentation. -
THE GROWTH of SHEEP MOUNTAIN ANTICLINE: COMPARISON of FIELD DATA and NUMERICAL MODELS Nicolas Bellahsen and Patricia E
THE GROWTH OF SHEEP MOUNTAIN ANTICLINE: COMPARISON OF FIELD DATA AND NUMERICAL MODELS Nicolas Bellahsen and Patricia E. Fiore Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305 e-mail: [email protected] be explained by this deformed basement cover interface Abstract and does not require that the underlying fault to be listric. In his kinematic model of a basement involved We study the vertical, compression parallel joint compressive structure, Narr (1994) assumes that the set that formed at Sheep Mountain Anticline during the basement can undergo significant deformations. Casas early Laramide orogeny, prior to the associated folding et al. (2003), in their analysis of field data, show that a event. Field data indicate that this joint set has a basement thrust sheet can undergo a significant heterogeneous distribution over the fold. It is much less penetrative deformation, as it passes over a flat-ramp numerous in the forelimb than in the hinge and geometry (fault-bend fold). Bump (2003) also discussed backlimb, and in fact is absent in many of the forelimb how, in several cases, the basement rocks must be field measurement sites. Using 3D elastic numerical deformed by the fault-propagation fold process. models, we show that early slip along an underlying It is noteworthy that basement deformation often is thrust fault would have locally perturbed the neglected in kinematic (Erslev, 1991; McConnell, surrounding stress field, inducing a compression that 1994), analogue (Sanford, 1959; Friedman et al., 1980), would inhibit joint formation above the fault tip. and numerical models. This can be attributed partially Relating the absence of joints in the forelimb to this to the fact that an understanding of how internal stress perturbation, we are able to constrain the deformation is delocalized in the basement is lacking. -
Advanced Mechanics of Materials
ADVANCED MECHANICS OF MATERIALS By Dr. Sittichai Seangatith SCHOOL OF CIVIL ENGINEERING INSTITUTE OF ENGINEERING SURANAREE UNIVERSITY OF TECHNOLOGY May 2001 SURANAREE UNIVERSITY OF TECHNOLOGY INSTITUTE OF ENGINEERING SCHOOL OF CIVIL ENGINEERING 410 611 ADVANCED MECHANICS OF MATERIALS 1st Trimester /2002 Instructor: Dr. Sittichai Seangatith ([email protected]) Prerequisite: 410 212 Mechanics of Materials II or consent of instructor Objectives: Students successfully completing this course will 1. understand the concept of fundamental theories of the advanced mechanics of material; 2. be able to simplify a complex mechanic problem down to one that can be analyzed; 3. understand the significance of the solution to the problem of any assumptions made. Textbooks: 1. Advanced Mechanics of Materials; 4th Edition, A.P. Boresi and O.M. Sidebottom, John Wiley & Sons, 1985 2. Advanced Mechanics of Materials; 2nd Edition, R.D. Cook and W.C. Young, Prentice Hall, 1999 3. Theory of Elastic Stability; 2nd Edition, S.P. Timoshenko and J.M. Gere, McGraw-Hill, 1963 4. Theory of Elasticity; 3rd Edition, S.P. Timoshenko and J.N. Goodier, McGraw- Hill, 1970 5. Theory of Plates and Shells; 2nd Edition, S.P. Timoshenko and S. Woinowsky- Krieger, McGraw-Hill, 1970 6. Mechanical Behavior of Materials; 2nd Edition, N.E. Dowling, Prentice Hall, 1999 7. Mechanics of Materials; 3th Edition, R.C. Hibbeler, Prentice Hall, 1997 Course Contents: Chapters Topics 1 Theories of Stress and Strain 2 Stress-Strain Relations 3 Elements of Theory of Elasticity 4 Applications of Energy Methods 5 Static Failure and Failure Criteria 6 Fatigue 7 Introduction to Fracture Mechanics 8 Beams on Elastic Foundation 9 Plate Bending 10 Buckling and Instability Conduct of Course: Homework, Quizzes, and Projects 30% Midterm Examination 35% Final Examination 35% Grading Guides: 90 and above A 85-89 B+ 80-84 B 75-79 C+ 70-74 C 65-69 D+ 60-64 D below 60 F The above criteria may be changed at the instructor’s discretion. -
Stress Fields Around Dislocations the Crystal Lattice in the Vicinity of a Dislocation Is Distorted (Or Strained)
Stress Fields Around Dislocations The crystal lattice in the vicinity of a dislocation is distorted (or strained). The stresses that accompanied the strains can be calculated by elasticity theory beginning from a radial distance about 5b, or ~ 15 Å from the axis of the dislocation. The dislocation core is universally ignored in calculating the consequences of the stresses around dislocations. The stress field around a dislocation is responsible for several important interactions with the environment. These include: 1. An applied shear stress on the slip plane exerts a force on the dislocation line, which responds by moving or changing shape. 2. Interaction of the stress fields of dislocations in close proximity to one another results in forces on both which are either repulsive or attractive. 3. Edge dislocations attract and collect interstitial impurity atoms dispersed in the lattice. This phenomenon is especially important for carbon in iron alloys. Screw Dislocation Assume that the material is an elastic continuous and a perfect crystal of cylindrical shape of length L and radius r. Now, introduce a screw dislocation along AB. The Burger’s vector is parallel to the dislocation line ζ . Now let us, unwrap the surface of the cylinder into the plane of the paper b A 2πr GL b γ = = tanθ 2πr G bG τ = Gγ = B 2πr 2 Then, the strain energy per unit volume is: τ× γ b G Strain energy = = 2π 82r 2 We have identified the strain at any point with cylindrical coordinates (r,θ,z) τ τZθ θZ B r B θ r θ Slip plane z Slip plane A z G A b G τ=G γ = The elastic energy associated with an element is its θZ 2πr energy per unit volume times its volume. -
Structural Geology of Parautochthonous and Allochthonous Terranes of the Penokean Orogeny in Upper Michigan Comparisons with Northern Appalachian Tectonics
Structural Geology of Parautochthonous and Allochthonous Terranes of the Penokean Orogeny in Upper Michigan Comparisons with Northern Appalachian Tectonics U.S. GEOLOGICAL SURVEY BULLETIN 1904-Q AVAILABILITY OF BOOKS AND MAPS OF THE U.S. GEOLOGICAL SURVEY Instructions on ordering publications of the U.S. Geological Survey, along with the last offerings, are given in the current-year issues of the monthly catalog "New Publications of the U.S. Geological Survey." Prices of available U.S. Geological Survey 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 monthly, which is for sale in microfiche from the U.S. Geological Survey, Book and Open-File Report Sales, Box 25286, Building 810, Denver Federal Center, Denver, CO 80225 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, Tech Books of the U.S. Geological Survey are available over the niques of Water-Resources Investigations, Circulars, publications counter at the following U.S. Geological Survey offices, all of of general interest (such as leaflets, pamphlets, booklets), single which are authorized agents of the Superintendent of Documents. copies of periodicals (Earthquakes & Volcanoes, Preliminary De termination of Epicenters), and some miscellaneous reports, includ ANCHORAGE, Alaska-Rm. -
Evidence for Controlled Deformation During Laramide Orogeny
Geologic structure of the northern margin of the Chihuahua trough 43 BOLETÍN DE LA SOCIEDAD GEOLÓGICA MEXICANA D GEOL DA Ó VOLUMEN 60, NÚM. 1, 2008, P. 43-69 E G I I C C O A S 1904 M 2004 . C EX . ICANA A C i e n A ñ o s Geologic structure of the northern margin of the Chihuahua trough: Evidence for controlled deformation during Laramide Orogeny Dana Carciumaru1,*, Roberto Ortega2 1 Orbis Consultores en Geología y Geofísica, Mexico, D.F, Mexico. 2 Centro de Investigación Científi ca y de Educación Superior de Ensenada (CICESE) Unidad La Paz, Mirafl ores 334, Fracc.Bella Vista, La Paz, BCS, 23050, Mexico. *[email protected] Abstract In this article we studied the northern part of the Laramide foreland of the Chihuahua Trough. The purpose of this work is twofold; fi rst we studied whether the deformation involves or not the basement along crustal faults (thin- or thick- skinned deformation), and second, we studied the nature of the principal shortening directions in the Chihuahua Trough. In this region, style of deformation changes from motion on moderate to low angle thrust and reverse faults within the interior of the basin to basement involved reverse faulting on the adjacent platform. Shortening directions estimated from the geometry of folds and faults and inversion of fault slip data indicate that both basement involved structures and faults within the basin record a similar Laramide deformation style. Map scale relationships indicate that motion on high angle basement involved thrusts post dates low angle thrusting. This is consistent with the two sets of faults forming during a single progressive deformation with in - sequence - thrusting migrating out of the basin onto the platform. -
24. Structure and Tectonic Stresses in Metamorphic Basement, Site 976, Alboran Sea1
Zahn, R., Comas, M.C., and Klaus, A. (Eds.), 1999 Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 161 24. STRUCTURE AND TECTONIC STRESSES IN METAMORPHIC BASEMENT, SITE 976, ALBORAN SEA1 François Dominique de Larouzière,2,3 Philippe A. Pezard,2,4 Maria C. Comas,5 Bernard Célérier,6 and Christophe Vergniault2 ABSTRACT A complete set of downhole measurements, including Formation MicroScanner (FMS) high-resolution electrical images and BoreHole TeleViewer (BHTV) acoustic images of the borehole wall were recorded for the metamorphic basement section penetrated in Hole 976B during Ocean Drilling Program Leg 161. Because of the poor core recovery in basement (under 20%), the data and images obtained in Hole 976B are essential to understand the structural and tectonic context wherein this basement hole was drilled. The downhole measurements and high-resolution images are analyzed here in terms of structure and dynamics of the penetrated section. Electrical resistivity and neutron porosity measurements show a generally fractured and consequently porous basement. The basement nature can be determined on the basis of recovered sections from the natural radioactivity and photoelectric fac- tor. Individual fractures are identified and mapped from FMS electrical images, providing both the geometry and distribution of plane features cut by the hole. The fracture density increases in sections interpreted as faulted intervals from standard logs and hole-size measurements. Such intensively fractured sections are more common in the upper 120 m of basement. While shallow gneissic foliations tend to dip to the west, steep fractures are mostly east dipping throughout the penetrated section. Hole ellipticity is rare and appears to be mostly drilling-related and associated with changes in hole trajectory in the upper basement schists. -
Factors Contributing to the Formation of Sheeting Joints
FACTORS CONTRIBUTING TO THE FORMATION OF SHEETING JOINTS: A STUDY OF SHEETING JOINTS ON A DOME IN YOSEMITE NATIONAL PARK A THESIS SUBMITTED TO THE GRADUATE DIVISION OF THE UNIVERSITY OF HAWAI„I AT MĀNOA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTERS OF SCIENCE IN GEOLOGY AND GEOPHYSICS AUGUST 2010 By Kelly J. Mitchell Thesis Committee: Steve Martel, Chairperson Fred Duennebier Paul Wessel Keywords: sheeting joints, exfoliation joints, topographic stresses, curvature, mechanics, spectral filtering, Yosemite Acknowledgements I would like to extend my sincerest gratitude to those who helped make this thesis possible. Thanks to the National Science Foundation for funding this research. Thank you to my graduate advisor, Dr. Steve Martel, for your advice and support through the past few years. This has been a long and difficult project but you have been patient and supportive through it all. Special thanks to my committee, Dr. Fred Duennebier and Dr. Paul Wessel for their advice and contributions; without your help I do not think this project would have been possible. I appreciate the time all of you have spent discussing the project with me. Thank you to Chris Hurren, Shay Chapman, and Carolyn Parcheta for your hard work and moral support in the field; you kept a great attitude during the field season. Special thanks to the National Park Service staff in Yosemite, particularly Dr. Greg Stock and Brian Huggett for their assistance. I wish to thank NCALM, Ole Kaven, Nicholas VanDerElst, and Emily Brodsky for LIDAR data collection. Thank you to Carolina Anchietta Fermin, Lisa Swinnard, and Darwina Griffin for their moral support. -
Fault Characterization by Seismic Attributes and Geomechanics in a Thamama Oil Field, United Arab Emirates
GeoArabia, Vol. 9, No. 2, 2004 Gulf PetroLink, Bahrain Fault characterization, Thamama oil field, UAE Fault characterization by seismic attributes and geomechanics in a Thamama oil field, United Arab Emirates Yoshihiko Tamura, Futoshi Tsuneyama, Hitoshi Okamura and Keiichi Furuya ABSTRACT Faults and fractures were interpreted using attributes that were extracted from a 3-D seismic data set recorded over a Lower Cretaceous Thamama oil field in offshore Abu Dhabi, United Arab Emirates. The Thamama reservoir has good matrix porosity (frequently exceeding 20%), but poor permeability (averaging 15 mD). Because of the low permeability, faults and fractures play an important role in fluid movement in the reservoir. The combination of the similarity and dip attributes gave clear images of small-displacement fault geometry, and the orientation of subseismic faults and fractures. The study better defined faults and fractures and improved geomechanical interpretations, thus reducing the uncertainty in the preferred fluid-flow direction. Two fault systems were recognized: (1) the main NW-trending fault system with mapped fault-length often exceeding 5 km; and (2) a secondary NNE-trending system with shorter faults. The secondary system is parallel to the long axis of the elliptical domal structure of the field. Some of the main faults appear to be composed of en- echelon segments with displacement transfer between the overlapping normal faults (relay faults with relay ramps). The fault systems recognized from the seismic attributes were correlated with well data and core observations. About 13 percent of the fractures seen in cores are non-mineralized. The development of the fault systems was studied by means of clay modeling, computer simulation, and a regional tectonics review. -
Surficial-Geologic Reconnaissance and Scarp Profiling on The
Surficial-Geologic Reconnaissance and Scarp Profiling on the Collinston and Clarkston Mountain Segments of the Wasatch Fault Zone, Box Elder County, Utah – Paleoseismic Inferences, Implications for Adjacent Segments, and Issues for Diffusion-Equation Scarp-Age Modeling Paleoseismology of Utah, Volume 15 By Michael D. Hylland SPECIAL STUDY 121 UTAH GEOLOGICAL SURVEY a division of Utah Department of Natural Resources 2007 Surficial-Geologic Reconnaissance and Scarp Profiling on the Collinston and Clarkston Mountain Segments of the Wasatch Fault Zone, Box Elder County, Utah – Paleoseismic Inferences, Implications for Adjacent Segments, and Issues for Diffusion-Equation Scarp-Age Modeling Paleoseismology of Utah, Volume 15 By Michael D. Hylland ISBN 1-55791-763-9 SPECIAL STUDY 121 UTAH GEOLOGICAL SURVEY a division of Utah Department of Natural Resources 2007 STATE OF UTAH Jon Huntsman, Jr., Governor DEPARTMENT OF NATURAL RESOURCES Michael Styler, Executive Director UTAH GEOLOGICAL SURVEY Richard G. Allis, Director PUBLICATIONS contact Natural Resources Map/Bookstore 1594 W. North Temple Salt Lake City, UT 84116 telephone: 801-537-3320 toll-free: 1-888-UTAH MAP Web site: http://mapstore.utah.gov email: [email protected] THE UTAH GEOLOGICAL SURVEY contact 1594 W. North Temple, Suite 3110 Salt Lake City, UT 84116 telephone: 801-537-3300 fax: 801-537-3400 Web site: http://geology.utah.gov Although this product represents the work of professional scientists, the Utah Department of Natural Resources, Utah Geological Survey, makes no war- ranty, expressed or implied, regarding its suitability for a particular use. The Utah Department of Natural Resources, Utah Geological Survey, shall not be liable under any circumstances for any direct, indirect, special, incidental, or consequential damages with respect to claims by users of this product.