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SEPM (Society for Sedimentary Geology) sponsored a research conference
entitled "Graphic Corelation and the Composite Standard: The Methods
and Their Application" in Houston, Texas, November 27 to December 2,
1994. I attended and "volunteered" to provide a review for PaleoNet,
so here goes...
The meeting, organized by Rich Lane (Amoco), Gregg Blake (Unocal) and
Norman MacCleod (Natural History Museum, London), drew about 60
registrants from industry, academia and museums. The focus of the
conference was "to examine the long-standing concepts of graphic
correlation and composite standard development in light of current
computer capabilities and in relation to the demands for higher
resolution biostratigraphic correlation."
The program began with a review of the under-utilized technique of
graphic correlation developed by Alan Shaw (1964) and summarized by
F.X. Miller (1977). The review was given by Ray Christopher (ARCO) and
Bob Pierce (Amoco) served to get us neophytes acquainted with what
graphic correlation is and how it works. This technique holds the
promise of very precise correlation of stratigraphic sections using
multiple data sets by cross plotting events against a "composite
standard" developed for the area.
The two and a half days of technical presentations focused on
applications of graphic correlation to real data sets ranging from
outcrop sections accross the K-T boundary to hydrocarbon exploration
data from the North Sea. An interesting "extra" was the the unrolling of
a series of Amoco biostratigraphic range charts for the Jurassic to the
Recent and showing the range of all fossils observed against the Amoco
corporate composite standard. Placed end to end the charts stretched
for a good 60 feet across the hall. The technical sessions were
followed by a three day field trip (which I could not attend, but which
received very good reviews) to examine sections where detailed graphic
correlations have been made.
Key points from the conference include:
1. Graphic correlation offers an objective method of precise
correlation of stratigraphic sections.
2. Graphic correlation compares all available data (multiple fossil
groups and even non-biological "event" data) rather than a few
indicator species.
3. Computer software such as Ken Hood's GraphCor, Norman MacLeod's
Macintosh HyperCard 'Shaw Stack', and Amoco's proprietary Unix-based
system have streamlined the production of graphic correlation plots,
making the technique much more attractive by avoiding the tedious hand
plotting of data.
4. The technique and other quantitative techniques (such as RASC) are
not panaceas and much of their value depends upon the quality of the
initial data sets. Much effort must be spent on "cleaning up" the
initial data to produce meaningful results (especially when using
data from more than one worker where species concepts may differ).
The research conference was an excellent showcase for the unique role
of paleontology in resolving stratigraphic problems. Paleontology
has much to offer and the careful application of quantitative
techniques holds the promise of very high stratigraphic resolution.
The objectivity of quantitative techniques and the precision they can
deliver may go a long way toward improving credibility of
biostratigraphy when compared to seismic and/or wireline log
correlations within oil companies.
I have just purchased a copy of a graphic correlation software
package and look forward to testing the technique on my own data.
Below are the references cited and a listing of the technical papers
and authors.
Seasons Greetings to All,
Brian
=========================================================================
Brian J. O'Neill Phone: (504) 588-4351
Shell Offshore Inc. Room: OSS-2916
P.O. Box 61933 E-mail: boneill@shell.com
New Orleans LA 70161 Profs: bjo5
=========================================================================
Shaw, A.B., 1964, Time in Stratigraphy, McGraw-Hill Book Co., New
York, 365 pp.
Miller, F.X., 1977, The graphic correlation method in biostratigraphy,
pp. 165-186, in E.G. Kaufman and J.E. Hazel, Concepts and Methods of
Biostratigraphy, Dowden, Hutchinson & Ross, Inc., Stroudsburg, Penn.,
658 p.
---------- Oral and Poster Sessions------------------------
Gradstein, F. Keynote Address: Crunching Bugs - Quantitative
biostratigraphy for explorationists.
Kleffner, M.A., A conodont- and graptolite-based Silurian
chronostratigraphy and development of a Silurian time scale by graphic
correlation.
Woollam, R., Stratigraphic analysis of Jurassic dinoflagellate cyst
distribution in the Troll Field (Norwegian Sector, North Sea) using
Graphic Correlation.
Scott, R.W. J.A. Bergen, M.J. Evetts, E.J. Kidson, P.C. Franks, Graphic
correlation calibrates ages of mid-Cretaceous depositional cycles,
Western Interior.
Pierce, R.W. and F.X. Miller, Gulf of Suez Miocene composite standard.
McLaughlin, P.P., Jr. and K.C. Hood, Regional chronostratigraphic
analysis of North Africa and the Arabian Plate - An example of graphic
correlation analysis using maximum and average composite sections
Athersuch, J., Strata bugs biostratigraphy database systems by Strata
Data Ltd.
Sadler, P and W. Kemple, Extending graphic correlation to many
dimensions.
Scott, R.W., P.G. Fincannon, and A.L. Brown, Interface for
biostratigraphic data with seismic data in the workstation.
Blake, G. and A. Gary, Application of quantitative biostratigraphy in
complex tectonic settings, offshore Trinidad.
Baseman, J.F. and P.L Brenckle, Application of composite standard
methodology for local correlation of the Mississippian-Pennsylvanian
Lisburne group in Northeastern Alaska.
Van Nieuwenhuise, D.S., Calibration of Jurassic maximum flooding
surfaces to a regional composite standard in the North Sea.
Agterberg, F., Three-dimensional ranking and scaling of biostrtigraphic
events.
Aurisano, R.W., Palynostratigraphy, graphic correlation, and the
Albian-Cenomanian boundary, offshore Gabon and Congo.
MacLeod, N., Graphic correlation and the Cretaceous-Tertiary (K/T)
boundary controversy: Countering old objections with new data.
Hazel, J., Graphic correlation fo the Eocene-Oligocene boundary
stratotype at Massignano, Italy.
Krebs, Graphic Correltion of the nonmarine late Miocene Chalk Hills
foramtion, Western Snake River Basin, Idaho.
Martin, R.W. and R.R. Fletcher, Graphic correlation of Plio-Pleistocene
sequence boundaries, Gulf of Mexico: Oxygen isotopes, ice volume and
sea level.
Partial index: