1.11 Crust and Lithospheric Structure – Global Crustal Structure W
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It Has Often Been Said That Studying the Depths of the Sea Is Like Hovering In
It has often been said that studying the depths of the sea is like hovering in a balloon high above an unknown land which is hidden by clouds, for it is a peculiarity of oceanic research that direct observations of the abyss are impracticable. Instead of the complete picture which vision gives, we have to rely upon a patiently put together mosaic representation of the discoveries made from time to time by sinking instruments and appliances into the deep. (Murray & Hjort, 1912: 22) Figure 1: Portrait of the H.M.S. Challenger. Prologue: Simple Beginnings In 1872, the H.M.S Challenger began its five- year journey that would stretch across every ocean on the planet but the Arctic. Challenger was funded for a single reason; to examine the mysterious workings of the ocean below its surface, previously unexplored. Under steam power, it travelled over 100,000 km and compiled 50 volumes of data and observations on water depth, temperature and conditions, as well as collecting samples of the seafloor, water, and organisms. The devices used to collect this data, while primitive by today’s standards and somewhat imprecise, were effective at giving humanity its first in-depth look into the inner workings of the ocean. By lowering a measured rope attached to a 200 kg weight off the edge of the ship, scientists estimated the depth of the ocean. A single reading could take up to 80 minutes for the weight to reach bottom. Taking a depth measurement also necessitated that the Challenger stop moving, and accurate mapping required a precise knowledge of where the ship was in the world, using navigational tools such as sextants. -
Cumulated Bibliography of Biographies of Ocean Scientists Deborah Day, Scripps Institution of Oceanography Archives Revised December 3, 2001
Cumulated Bibliography of Biographies of Ocean Scientists Deborah Day, Scripps Institution of Oceanography Archives Revised December 3, 2001. Preface This bibliography attempts to list all substantial autobiographies, biographies, festschrifts and obituaries of prominent oceanographers, marine biologists, fisheries scientists, and other scientists who worked in the marine environment published in journals and books after 1922, the publication date of Herdman’s Founders of Oceanography. The bibliography does not include newspaper obituaries, government documents, or citations to brief entries in general biographical sources. Items are listed alphabetically by author, and then chronologically by date of publication under a legend that includes the full name of the individual, his/her date of birth in European style(day, month in roman numeral, year), followed by his/her place of birth, then his date of death and place of death. Entries are in author-editor style following the Chicago Manual of Style (Chicago and London: University of Chicago Press, 14th ed., 1993). Citations are annotated to list the language if it is not obvious from the text. Annotations will also indicate if the citation includes a list of the scientist’s papers, if there is a relationship between the author of the citation and the scientist, or if the citation is written for a particular audience. This bibliography of biographies of scientists of the sea is based on Jacqueline Carpine-Lancre’s bibliography of biographies first published annually beginning with issue 4 of the History of Oceanography Newsletter (September 1992). It was supplemented by a bibliography maintained by Eric L. Mills and citations in the biographical files of the Archives of the Scripps Institution of Oceanography, UCSD. -
Imaging Through Gas Clouds: a Case History in the Gulf of Mexico S
Imaging Through Gas Clouds: A Case History In The Gulf Of Mexico S. Knapp1, N. Payne1, and T. Johns2, Seitel Data1, Houston, Texas: WesternGeco2, Houston, Texas Summary Results from the worlds largest 3D four component OBC seismic survey will be presented. Located in the West Cameron area, offshore Gulf of Mexico, the survey operation totaled over 1000 square kilometers and covered more than 46 OCS blocks. The area contains numerous gas invaded zones and shallow gas anomalies that disturb the image on conventional 3D seismic, which only records compressional data. Converted shear wave data allows images to be obtained that are unobstructed by the gas and/or fluids. This reduces the risk for interpretation and subsequent appraisal and development drilling in complex areas which are clearly petroleum rich. In addition, rock properties can be uniquely determined from the compressional and shear data, allowing for improved reservoir characterization and lithologic prediction. Data acquisition and processing of multicomponent 3D datasets involves both similarities and differences when compared to conventional techniques. Processing for the compressional data is the same as for a conventional OBC survey, however, asymmetric raypaths for the converted waves and the resultant effects on fold-offset-azimuth distribution, binning and velocity determination require radically different processing methodologies. These issues together with methods for determining the optimal parameters of the Vp/Vs ratio (γ) will be discussed. Finally, images from both the compressional (P and Z components summed) and converted shear waves will be shown to illuminate details that were not present on previous 3D datasets. Introduction Multicomponent 3D surveys have become one of the leading areas where state of the art technology is being applied to areas where the exploitation potential has not been fulfilled due to difficulties in obtaining an interpretable seismic image (MacLeod et al 1999, Rognoe et al 1999). -
Seismic Reflection and Refraction Methods
Seismic Reflection and Refraction Methods A. K. Chaubey National Institute of Oceanography, Dona Paula, Goa-403 004. [email protected] Introduction and radar systems. Whereas, in seismic refraction Seismic reflection and refraction is the principal method, principal portion of the wave-path is along the seismic method by which the petroleum industry explores interface between the two layers and hence hydrocarbon-trapping structures in sedimentary basins. approximately horizontal. The travel times of the Its extension to deep crustal studies began in the 1960s, refracted wave paths are then interpreted in terms of the and since the late 1970s these methods have become depths to subsurface interfaces and the speeds at which the principal techniques for detailed studies of the deep wave travels through the subsurface within each layer. crust. These methods are by far the most important For both types of paths the travel time depends upon the geophysical methods and the predominance of these physical property, called elastic parameters, of the methods over other geophysical methods is due to layered Earth and the attitudes of the beds. The various factors such as the higher accuracy, higher objective of the seismic exploration is to deduce resolution and greater penetration. Further, the information about such beds especially about their importance of the seismic methods lies in the fact that attitudes from the observed arrival times and from the data, if properly handled, yield an almost unique and variations in amplitude, frequency and wave form. unambiguous interpretation. These methods utilize the principle of elastic waves travelling with different Both the seismic techniques have specific velocities in different layer formations of the Earth. -
Proceedings of the Fifth International Congress on the History of Oceanography
EVOLUTION OF THE TECTOGENE CONCEPT, 1930-1965 ALlIN O. ALLWARDT SANTA CRUZ, CALIFORNIA Prepared for the Proceedings of the Fifth International congress on the History of oceanography (SCripps Institution of OCeanography, July 7-14, 1993) EVOLUTION OF THE TECTOGENR CONCEPT, 1930-1965 ABSTRACT The tectogene, or crustal downbuckle, was proposed in the early 19305 by F. A. Vening Meinesz to explain the unexpected belts of negative gravity anomalies in island arcs. He attributed the isostatic imbalance to a deep sialic root resulting from the action of subcrustal convection currents. Vening Heinesz's model was initially corroborated experimentally by P. H. Kuenen, but additional experiments by D. T. Griggs and geological analysis by H. H. Hess in the late 19305 led to substantial revision in detail. As modified, the tectogene provided a plausible model for the evolution of island arcs into alpine mountain belts for another two decades. Additional revisions became necessary in the early 19505 to accommodate the unexpected absence of sialic crust in the Caribbean and the marginal seas of the western Pacific. By 1960 the cherished analogy between island arcs and alpine mountain belts had collapsed under the weight of the detailed field investigations by Hess and his students in the Caribbean region. Hess then incorporated a highly modified form of the tectogene into his sea-floor spreading hypothesis. Ironically, this final incarnation of the concept preserved some of the weaker aspects of the 19305 original, such as the ad hoc explanation for the regular geometry of island arcs. EVOLUTION OF THE TECTOGENE CONCEPT, 1930-1965 ALAN O. -
Extended Abstracts
CONJUGATE MARGINS CONFERENCE 2018 Celebrating 10 years of the CMC: Pushing the Boundaries of Knowledge Extended Abstracts Dalhousie University, Halifax, Nova Scotia, August 19–22, 2018 ISBN: 0-9810595-8 CONJUGATE MARGINS CONFERENCE 2018 Celebrating 10 years of the CMC: Pushing the Boundaries of Knowledge 2 Dalhousie University, Halifax, Nova Scotia, August 19–22, 2018 CONJUGATE MARGINS CONFERENCE 2018 Celebrating 10 years of the CMC: Pushing the Boundaries of Knowledge CONJUGATE MARGINS CONFERENCE 2018 Celebrating 10 years of the CMC: Pushing the Boundaries of Knowledge Extended Abstracts 19-22 August 2018 Dalhousie University Halifax, Nova Scotia, Canada Editors: Ricardo L. Silva, David E. Brown, and Paul J. Post ISBN: 0-9810595-8 Dalhousie University, Halifax, Nova Scotia, August 19–22, 2018 3 CONJUGATE MARGINS CONFERENCE 2018 Celebrating 10 years of the CMC: Pushing the Boundaries of Knowledge 4 Dalhousie University, Halifax, Nova Scotia, August 19–22, 2018 CONJUGATE MARGINS CONFERENCE 2018 Celebrating 10 years of the CMC: Pushing the Boundaries of Knowledge Sponsors The organizers of the Conjugate Margins Conference sincerely thank our sponsors, partners, and supporters who contributed financially and/or in-kind to the Conference’s success. Diamond $15,000+ Platinum $10,000 – $14,999 Gold $6,000 – $9,999 and In-Kind Bronze $2,000 – $3,999 and In-Kind Patrons and Supporters $1,000 – $1,999 and In-Kind Dalhousie University, Halifax, Nova Scotia, August 19–22, 2018 5 CONJUGATE MARGINS CONFERENCE 2018 Celebrating 10 years of the CMC: Pushing the Boundaries of Knowledge 6 Dalhousie University, Halifax, Nova Scotia, August 19–22, 2018 CONJUGATE MARGINS CONFERENCE 2018 Celebrating 10 years of the CMC: Pushing the Boundaries of Knowledge Halifax 2018 Organization Organizing Committee David E. -
Fault Deformation, Seismic Amplitude and Unsupervised Fault Facies Analysis: Snøhvit Field, Barents Sea
Accepted Manuscript Fault deformation, seismic amplitude and unsupervised fault facies analysis: Snøhvit Field, Barents Sea Jennifer Cunningham, Nestor Cardozo, Christopher Townsend, David Iacopini, Gard Ole Wærum PII: S0191-8141(18)30328-6 DOI: 10.1016/j.jsg.2018.10.010 Reference: SG 3761 To appear in: Journal of Structural Geology Received Date: 10 June 2018 Revised Date: 11 October 2018 Accepted Date: 11 October 2018 Please cite this article as: Cunningham, J., Cardozo, N., Townsend, C., Iacopini, D., Wærum, G.O., Fault deformation, seismic amplitude and unsupervised fault facies analysis: Snøhvit Field, Barents Sea, Journal of Structural Geology (2018), doi: https://doi.org/10.1016/j.jsg.2018.10.010. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. ACCEPTED MANUSCRIPT 1 Fault deformation, seismic amplitude and unsupervised fault facies 2 analysis: Snøhvit field, Barents Sea 3 Jennifer CUNNINGHAM * A, Nestor CARDOZO A, Christopher TOWNSEND A, David 4 IACOPINI B and Gard Ole WÆRUM C 5 A Department of Energy Resources, University of Stavanger, 4036 Stavanger, Norway 6 *[email protected] , +47 461 84 478 7 [email protected] , [email protected] 8 9 BGeology and Petroleum Geology, School of Geosciences, University of Aberdeen, Meston 10 Building, AB24 FX, UK 11 [email protected] 12 C Equinor ASA, Margrete Jørgensens Veg 4, 9406 Harstad, Norway 13 [email protected] 14 15 Keywords: faults, dip distortion, seismic attributes, seismic amplitude, fault facies. -
Annual Report 2019 Annual Report SM Approved by the SEG Council, 17 June 2020 Connecting the World of Applied Geophysics
2019 Annual Report 2019 Annual Report SM Approved by the SEG Council, 17 June 2020 Connecting the World of Applied Geophysics REPORTS OF Second vice Director at large REPORTS OF Books Editorial Distinguished GEOPHYSICS SEG BOARD OF president Maria A. Capello COMMITTEES Board Instructor Valentina Socco, editor DIRECTORS Manika Prasad 13 Mauricio Sacchi, chair Short Course 31 10 AGU–SEG 24 Adel El-Emam, chair President Director at large Collaboration 27 Geoscientists Robert R. Stewart Treasurer and Paul S. Cunningham Chi Zhang, cochair Committee on Without Borders® 5 Finance Committee 14 20 University and Distinguished Robert Merrill, chair Dan Ebrom and Lee Student Programs Lecturer 34 President-elect Bell Director at large Annual Meeting Joan Marie Blanco, Gerard Schuster, chair Rick Miller 11 David E. Lumley Steering chair 28 Global Advisory 7 15 Glenn Winters, chair 25 George Buzan, chair Vice president, 20 Emerging 36 Past president Publications Director at large Continuing Professionals Nancy House Sergey Fomel Ruben D. Martinez Annual Meeting Education International Gravity and 8 12 16 Technical Program Malcolm Lansley, chair Johannes Douma, chair Magnetics Dimitri Bevc, chair 25 30 Luise Sander, chair First vice president Chair of the Council Director at large Olga Nedorub, cochair 36 Alexander Mihai Gustavo Jose Carstens Kenneth M. Tubman 22 Development and EVOLVE Popovici 12 16 Production Michael C. Forrest, Health, Safety, 9 Audit Andrew Royle, chair interim chair Security, and Director at large Executive director Bob Brook, chair -
Reflection Seismic Method
GEOL463 ReflectionReflection SeismicSeismic MethodMethod Principles Data acquisition Processing Data visualization Interpretation* Linkage with other geophysical methods* Reading: Gluyas and Swarbrick, Section 2.3 Many books on reflection seismology (e.g., Telford et al.) SeismicSeismic MethodMethod TheThe onlyonly methodmethod givinggiving completecomplete picturepicture ofof thethe wholewhole areaarea GivesGives byby farfar thethe bestbest resolutionresolution amongamong otherother geophysicalgeophysical methodsmethods (gravity(gravity andand magnetic)magnetic) However, the resolution is still limited MapsMaps rockrock propertiesproperties relatedrelated toto porosityporosity andand permeability,permeability, andand presencepresence ofof gasgas andand fluidsfluids However, the links may still be non-unique RequiresRequires significantsignificant logisticallogistical efforteffort ReliesRelies onon extensiveextensive datadata processingprocessing andand inversioninversion GEOL463 SeismicSeismic ReflectionReflection ImagingImaging Acoustic (pressure) source is set off near the surface… Sound waves propagate in all directions from the source… This is the “ideal” 0.1-10% of the energy reflects of seismic imaging – flat surface and from subsurface contrasts… collocated sources This energy is recorded by and receivers surface or borehole “geophones”… In practice, multi-fold, offset recording is Times and amplitudes of these used, and zero-offset section is obtained by reflections are used to interpret extensive data the subsurface… processing -
Ocean Margin Drilling
Ocean Margin Drilling May 1980 NTIS order #PB80-198302 Library of Congress Catalog Card Number 80-600083 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 Stock No. 052-003-00754-1 PREFACE This Technical Memorandum was prepared in response to a request from the Chairman and the Ranking Minority Member of the HUD-Independent Agencies Subcommittee of the Senate Appropriations Committee. The Committee requested that OTA conduct an evaluation of the Ocean Margin Drilling Program, a major new public-private cooperative research effort in marine geology proposed by the National Science Foundation. They were particularly interested in the scientific merits of the program and whether other, less costly alternatives could yield the same or greater scientific return. Because OTA already had a more general ongoing study of ocean research technology, the agency was able to respond quickly to this request. The Memorandum was prepared with the advice and assistance of a small panel of scientists plus a much broader group of scientists, engineers, petroleum company representatives, and others who submitted material for our use and reviewed our draft report. The study discusses the scientific merit of the program, possible alternatives to the present program plan, problems associated with technology development, aspects of petroleum company participation in the program, and government management considerations. There are also appendices including specific alternatives proposed by the OTA panel members and historical factors leading to the present plans. JOHN H. GIBBONS Director iii OTA Staff for Review of the Ocean Margin Drilling Program Robert Niblock, Ocean Program Manager Peter A. -
Changing Prodcutivity in U.S. Petroleum Exploration And
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Research Papers in Economics CHANGING PRODUCTIVITY IN U.S. PETROLEUM EXPLORATION AND DEVELOPMENT Douglas R. Bohi Charles River Associates Washington, D.C. Discussion Paper 98-38 June 1998 1616 P Street, NW Washington, DC 20036 Telephone 202-328-5000 Fax 202-939-3460 © 1998 Resources for the Future. All rights reserved. No portion of this paper may be reproduced without permission of the author. Discussion papers are research materials circulated by their authors for purposes of information and discussion. They have not undergone formal peer review or the editorial treatment accorded RFF books and other publications. Changing Productivity in U.S. Petroleum Exploration and Development Douglas R. Bohi Abstract This study analyzes sources of productivity change in petroleum exploration and development in the United States over the last ten years. There have been several major developments in the industry over the last decade that have led to dramatic reductions in the cost of finding and developing oil and natural gas resources. While some of the cost savings are organizational and institutional in nature, the most important changes are in the application of new technologies used to find and produce oil and gas: 3D seismology, horizontal drilling, and deepwater drilling. Not all the innovation is endogenous to the industry; some rests on outside advances (such as advances in high-speed computing that enabled 3D seismology), as well as learning-by-doing. The increased productivity of mature petroleum provinces like the U.S. helps to maintain competition in the world oil market as well as enhance domestic industry returns. -
SEISMIC REFLECTION METHODS APPLIED to ENGINEERING, ENVIRONMENTAL, and GROUND-WATER PROBLEMS by Don W
SEISMIC REFLECTION METHODS APPLIED TO ENGINEERING, ENVIRONMENTAL, AND GROUND-WATER PROBLEMS by Don W. Steeples and Richard D. Miller Kansas Geological Survey The University of Kansas Lawrence, Kansas ABSTRACT The seismic-reflection method is a powerful geophysical exploration method that has been in widespread use in the petroleum industry for more than 60 years. Since 1980, it has been increasingly used in applications shallower than 30 m, and that is the principal subject of this paper. The seismic-reflection method measures different parameters than other geophysical methods, and it requires careful attention to avoid possible pitfalls in data collection, processing, and interpretation. Part of the key to avoiding the pitfalls is to understand the resolution limits of the technique, and to carefully plan shallow-reflection surveys around the geologic objective and the resolution limits. Careful planning is also necessary to make the method increasingly cost effective relative to test drilling and/or other geophysical methods. The selection of seismic recording equipment, energy source, and data- acquisition parameters are often critical to the success of a shallow-reflection project. It is important to carefully follow known seismic reflections throughout the data-processing phase to avoid misinterpretation of things that look like reflections but are not. The shallow- reflection technique has recently been used in mapping bedrock beneath alluvium in the vicinity of hazardous waste sites, detecting abandoned coal mines, following the top of the saturated zone during a pump test in an alluvial aquifer, and in mapping shallow faults. As resolution improves and cost-effectiveness increases, other new applications will be added.