About This Item
- Full text of this item is not available.
- Abstract PDFAbstract PDF(no subscription required)
Share This Item
The AAPG/Datapages Combined Publications Database
Houston Geological Society Bulletin
Abstract
Abstract: High Frequency Sea Level Changes in
the Late Quaternary: Clues to Effective
Exploration in the Gulf Coast Neogene
By
Cyclic sequences occur worldwide in nearly every
stratigraphic sequence; they are particularly well developed
in deposits associated with large river systems. Superimposed
on cycles attributed to shifting sites of deposition are
those related to high frequency sea level changes. The large
data base for this study (including 471 deep foundation
borings, thousands of line kilometers of high-resolution
seismic, and sedimentological and dating analyses) represents
the best information on high
resolution
chrono- and
lithostratigraphy that is available on any modern continental
shelf/upper slope. These data are used to document sedimentological
characteristics, spatial depositional patterns,
and seismic/lithofacies response during three complete sea
level cycles over the entire continental shelf/upper slope of
offshore Louisiana.
Sedimentation during periods of high sea level is
characterized by: (a) thin, slowly accumulated depositional
sequences referred to as condensed section, (b) calcareous-rich
deposits, including hemipelagics and shell hashes, (c)
wide lateral
continuity, and (d) high amplitude acoustic
response. Sedimentation during periods of low sea level are
characterized by: (a) variable-thickness, rapidly accumulated
sequences referred to as expanded sections, (b)
coarse-grained clastic deposits, including abundant sands
and gravels, (c) well-defined depositional trends, and (d) a
wide variety of seismic responses.
Even though the data set covers only a short period of geologic time (240,000 years), these high frequency events are responsible for the deposition of excellent reservoir quality facies in well-defined and predictable trends. An understanding of the facies relationships resulting from these high frequency events will aid in the interpretation of the complex sequence of deeply buried Neogene sediments in the northern Gulf of Mexico basin and aid in correlation of the various lithofacies.
End_of_Record - Last_Page 8---------------