Last Data Base Update:
June, 2007
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Introduction
Background
Since its inception in January of 1989, the U.S Geological Survey
(USGS) Energy Resources Program Organic Geochemistry Laboratory
Data Base has grown to contain the analytical data for over 60,000
samples worldwide from more than 30 different data sources. The
Organic Geochemistry Data Base (OGDB) contains chemical analysis
data for crude oil, natural gas and rock samples analyzed by the
USGS Central Energy Resources Team's Organic Geochemistry Laboratory,
or by contracted-service laboratories. Data was also obtained
from the literature and unpublished public domain sources. The
sample types included are primarily rock, oil, and gas samples
collected from outcrops or from exploratory or production wells.
This information is used by the USGS for worldwide energy resource
sssessments based on the petroleum systems paradigm (source rock
- reservoir rock relation), and is periodically released to the
public. Analytical data within the OGDB includes Rock-Eval pyrolysis,
organic mass spectrometry, vitrinite reflectance, gas chromatography,
column chromatography, stable carbon isotopes and a number of
other related petroleum geochemistry analyses that, in some instances,
predate the OGDB. Throughout the years the Energy Program scientists
have utilized these data to not only develop an understanding
of the physical and geochemical processes responsible for hydrocarbon
formation, maturation, generation, migration and accumulation,
but also as a tool to assess the oil and gas potential for sedimentary
basins in both national and international settings.
System Requirements
The Data Base exists in both text (.txt) and Microsoft Access
(.mdb) formats. The downloaded .mdb can be queried directly in
any version of Microsoft Access 2000 or later. The text version
necessitates manual insertion of column definitions and all pertinent
metadata into whatever data base program the user wishes. Because
of the large size of the data file, a high-speed connection is
highly recommended for the download of either version of these
files.
About the Data Base
The OGDB consists of 12 data tables interrelated to the SAMPLES
table via the sample number. It should be noted that the sample
number is actually a text value. A complete metadata set is also
included in each released format. To successfully utilize the
dataset in either format, it is important for the user to become
thoroughly familiar with the accompanying metadata and data types.
In many instances, latitude and longitude site location information
for wells is derived from a USGS one-quarter mile grid system.
Refer to the Documentation page for more
information. Please note that because of the significant number
of data sources, laboratory techniques, and reporting units included
in this release, it is impossible for the author or the USGS to
guarantee the precision or accuracy of any individual data point.
Future Updates
Updates to the file are planned to occur approximately on an
annual basis. A GIS map browser with special data mapping capabilities
to further assist the user is now in the planning stages for a
future release of the OGDB.
Acknowledgements
The author greatly appreciates the cooperation of his fellow
USGS geochemists: Paul Lillis, J. David King, Augusta Warden,
and Michael Pribil, for their total dedication to this effort
and to Christopher Skinner, for the design and construction of
this website. In addition, the author offers his most sincere
thanks to the IHS Energy Group, Englewood, Colo., who, without
their cooperation would seriously hinder this information from
being available to the public.
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