Internal geometry and reservoir potential of some modern crevasse splay sands
Cores taken along strike and dip transects through the Baptiste Collette crevasse splay, modern Mississippi River Delta, have been analyzed to determine the sedimentologic nature and potential reservoir quality of modern crevasse splay sands. The stratigraphic framework is more complex than previously recognized. This is demonstrated by the presence of several fine-grained (61-125..mu..) sand bodies (1-2 m or 3-6 ft thick) reflecting deposition in three distinct environments. Subaerial levee sands, which thicken toward the proximal end of the splay, contain 50-80% fine-grained (88..mu..) sand, 10% interlaminated muds, and 5-25% rooting. Distributary-mouth bar and point bar deposits (2 m or 6 ft below mean sea level) are 50-60% finegrained sand (88..mu..) and 40-50% interlaminated mud, with 5% cross-bedding and a gradational base. The deeper (below 6 m or 18 ft) channel sands are 80-95% fine-grained (99-125..mu..) sand, with 20-75% cross-bedding, 10% interlaminated muds, and an erosional base. These correlatable sands are encased in thick, organic-rich, bioturbated, bay and abandoned channel muds forming an impermeable seal. Channel sands have the greatest reservoir potential, being more laterally continuous along dip, clean (<5% silt and clay), well sorted, fine grained, and more homogeneous with few permeability barriers (i.e., mud layers and laminae). This study should complement the limited knowledge of modern crevasse splay systems as well as provide insight into the exploration or enhanced recovery of hydrocarbons in ancient equivalents, such as the Admire 650-ft sandstone of Kansas.
- Research Organization:
- Louisiana Geological Survey, Baton Rouge
- OSTI ID:
- 6374193
- Report Number(s):
- CONF-8410143-
- Journal Information:
- Am. Assoc. Pet. Geol., Bull.; (United States), Journal Name: Am. Assoc. Pet. Geol., Bull.; (United States) Vol. 68:9; ISSN AAPGB
- Country of Publication:
- United States
- Language:
- English
Similar Records
Clay mineralogy of cubits gap crevasse splay, Mississippi delta
Adverse effects of crevasse-splay deposits in an Appalachian coal mine, eastern Kentucky
Related Subjects
020200* -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
ALLUVIAL DEPOSITS
GEOLOGIC DEPOSITS
GEOLOGY
LITHOLOGY
MINERAL RESOURCES
NATURAL GAS DEPOSITS
ORIGIN
PERMEABILITY
PETROLEUM DEPOSITS
POROSITY
RESERVOIR ROCK
RESOURCE POTENTIAL
RESOURCES
ROCKS
SAND
SANDSTONES
SEDIMENTARY ROCKS
STRATIGRAPHY