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VOL. 15, No. 10 A PUBLICATION OF THE GEOLOGICAL SOCIETY OF AMERICA OCTOBER 2005 Inside: Geologic processes in sedimentary basins inferred from three-dimensional seismic imaging, RICHARD J. DAVIES AND HENRY W. Geologic processes in sedimentary POSAMENTIER, p. 4 basins inferred from three-dimensional Penrose Conference Report, p. 28 Section Meetings: seismic imaging Southeastern Section, p. 11 North-Central Section, p. 15 VOLUME 15, NUMBER 10 OCTOBER 2005 Cover: Miocene carbonate platform charac- terized by extensive reef buildup and crosscut- ting tidal channels. The relief from platform to basin floor is ~200–250 m. The feature toward the top of the image is an isolated GSA TODAY publishes news and information for more than outlier buildup ~7 km wide. Data courtesy of 18,000 GSA members and subscribing libraries. GSA Today lead science articles should present the results of exciting new PGS Geophysical; permission to publish from research or summarize and synthesize important problems BPMIGAS and Anadarko Petroleum Corpora- or issues, and they must be understandable to all in the earth tion is gratefully acknowledged. See “Geo- science community. Submit manuscripts to science editors logic processes in sedimentary basins inferred Keith A. Howard, [email protected], or Gerald M. Ross, from three-dimensional seismic imaging,” by [email protected]. Richard J. Davies and Henry W. Posamentier, GSA TODAY (ISSN 1052-5173 USPS 0456-530) is published 11 p. 4–9. times per year, monthly, with a combined April/May issue, by The Geological Society of America, Inc., with offices at 3300 Penrose Place, Boulder, Colorado. Mailing address: P.O. Box 9140, Boulder, CO 80301-9140, USA. Periodicals postage paid at Boulder, Colorado, and at additional mailing offices. Postmaster: Send address changes to GSA Today, GSA Sales and Service, SCIENCE ARTICLE P.O. Box 9140, Boulder, CO 80301-9140. Copyright © 2005, The Geological Society of America, Inc. (GSA). All rights reserved. Copyright not claimed on content prepared 4 Geologic processes in sedimentary basins inferred wholly by U.S. government employees within scope of their from three-dimensional seismic imaging RICHARD J. DAVIES AND employment. Individual scientists are hereby granted permission, ENRY OSAMENTIER without fees or further requests to GSA, to use a single figure, a H W. P single table, and/or a brief paragraph of text in other subsequent works and to make unlimited photocopies of items in this journal for noncommercial use in classrooms to further education and science. For any other use, contact Copyright Permissions, GSA, P.O. 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Sajban Graphics Production: Margo Y. Sajban 30 GSA Foundation Update ADVERTISING: Classifieds & Display: Ann Crawford, 1-800-472-1988, ext. 1053, 33 Classified Advertising (303) 357-1053, Fax 303-357-1070; [email protected] GSA ONLINE: www.geosociety.org 37 Journal Highlights Printed in the USA using pure soy inks. 39 GeoMart Geoscience Directory 50% Total Recovered Fiber 10% Postconsumer is a three-dimensional cube of seismic Geologic processes in sedimentary reflections that can be interrogated using a wide range of interpretation basins inferred from three-dimensional software. Three-dimensional seismic coverage in mature hydrocarbon prov- seismic imaging inces can cover entire sedimentary basins, and global coverage is increas- Richard J. Davies, 3DLab, School of Earth, Ocean and Planetary Sciences, Main ing as acquisition, processing, hard- Building, Park Place, Cardiff University, Cardiff CF10 3YE, UK, richard.davies@earth. ware, and software costs are decreas- ing. The sheer vertical and lateral extent cf.ac.uk; Henry W. Posamentier, Anadarko Canada Corporation, 425 1st Street SW, of data coverage means that tens of Calgary, Alberta T2P4V4, Canada, [email protected] meters to basin-scale phenomena can be analyzed. The interpretation methodology is seismic reflection profiling is now shed- ABSTRACT riddled with buzzwords, many of which Three-dimensional seismic reflection ding light on fundamental geologic are specific to the growing number of data are now being used to understand processes that span a surprisingly wide software products that can be employed a range of fundamental geological pro- range of earth science disciplines, from to interpret and visualize these data. cesses. However, like most geological structural geology to geomorphology Seedpicking, autopicking, voxbodies, investigative tools, it is the products of to fluid migration through strata within and reflection attributes are a few of geological processes that are revealed sedimentary basins. the terms that have become part of by these data rather than the processes Like its medical counterpart, three- the seismic interpreter’s vocabulary themselves; processes inevitably need dimensional seismology is a form of (e.g., Brown, 1999). With specialized to be inferred. We outline how the remote sensing, a means of imaging the software, however, basic interpreta- interpretation of three-dimensional interior of a solid object in a noninva- tion procedures are straightforward. seismic data is undertaken in sedimen- sive way. The transmission of seismic Like any geologic mapping campaign, tary basins and then describe selected energy and the return of energy back interpretation usually starts with a phase examples of recent applications of these to the surface by reflection and refrac- of reconnaissance. Because the dis- data with the objective of showing how tion allows for some of the fabric and tance between seismic lines is so close sedimentary basin processes can be texture of Earth to be imaged, digitally (e.g., 12.5 m or 25 m), the data can be unraveled from seismic imagery. These enhanced, and evaluated. The resultant viewed as a contiguous earth cube. examples cover the diverse disciplines images capture snapshots of the sub- By panning through tens, hundreds, of (1) geomorphology and process sedi- surface at a moment in time, and analy- and thousands of seismic lines over mentology, (2) diagenetic processes, sis of a series of images facilitates the a matter of seconds and minutes, the (3) magma intrusion into the upper reconstruction of the geological evolu- subsurface can be animated, and the continental crust, and (4) fluid flow in tion of the subsurface. The scale of such geology “comes alive.” Panning through sedimentary basins. analysis ranges from whole Earth (e.g., multiple, closely spaced seismic sections Grand et al., 1997) to the relatively shal- INTRODUCTION represents the equivalent of viewing low parts of the crust examined in this As a byproduct of the search for an outcrop in a quarry wherein layer contribution. hydrocarbons, the earth science com- upon layer of vertical