Peat deposits in the Mississippi River deltaic plain

Conference · Tue Mar 01 04:00:00 EST 1983 · Am. Assoc. Pet. Geol., Bull.; (United States)

OSTI ID:6379214

Kosters, E; Bailey, A

The stratigraphy of the upper 4 m (13 ft) of the western Vermilion Bay area is that of a freshwater swamp (> 35% organic matter and abundant cypress wood fragments). Due to marine inundation, the present surface is covered with a saline marsh. The swamp deposit at 1 m (3 ft) depth possibly correlates with a marsh deposit at the same depth in eastern Vermilion Bay, where three depositional cycles, each containing blanket peats, can be recognized in the upper 9.5 m (31 ft) of the subsurface. The Barataria interdistributary basin displays a great horizontal and vertical organic matter variability. Characteristically, the peats average 90% moisture, 80% organic matter (20% ash), and a bulk density of 0.12 g/cm/sup 3/, the latter two numbers based on dry weight. The frequency distribution of organic matter percentage ranges, for all sediments, shows that in eastern Vermilion Bay 15% of the material is peat; by comparison, in Barataria basin, 5% of all material is peat. Preliminary results from mineralogical and elemental analyses of fresh and brackish peats indicate the presence of clay minerals, quartz, pyrite, gypsum, siliceous spicules, and smaller amounts of the trace mineral rutile. Minerals appear to vary with the type of peat. Elemental inorganic compositions also vary with depositional setting and post-depositional salt-water encroachment. Peat deposits in the deltaic plain show a great variability in stratigraphy and characteristics due to four conditions: (1) difference in depositional setting; (2) depth to the Pleistocene; (3) intermittent interruption of marsh growth by influx of detrital clastics; (4) marine inundation of freshwater peats.

• Research Organization: Louisiana Geology Survey, Baton Rouge
• OSTI ID: 6379214
• Report Number(s): CONF-8304200-
• Conference Information: Journal Name: Am. Assoc. Pet. Geol., Bull.; (United States) Journal Volume: 67:3
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
011000* -- Coal
Lignite
& Peat-- Reserves
Geology
& Exploration
DEPOSITION
ENERGY SOURCES
FOSSIL FUELS
FUELS
GEOLOGIC HISTORY
GEOLOGIC STRUCTURES
GEOLOGY
GULF COAST
MINERALOGY
MISSISSIPPI RIVER
NORTH AMERICA
ORGANIC MATTER
PEAT
RIVERS
SEDIMENTARY BASINS
STRATIGRAPHY
STREAMS
SURFACE WATERS
USA