Palynofacies of lignites and associated sediments in the upper paleocene Tuscahoma sand of southwestern Alabama and eastern Mississippi
- Geological Survey of Alabama, Tuscaloosa, AL (United States)
The Tuscahoma Sand of the Wilcox Group is composed of fine-grained sand, laminated sandy clay, marl and lignite. The Tuscahoma forms a poorly exposed belt from southeastern Alabama and extends northwestward into western Alabama and eastern Mississippi. The sand is assigned to the late Paleocene planktonic foraminiferal Morozovella velascoensis interval zone. Lignites in the Tuscahoma Sand occur as parasequence deposits in the highstand systems tract of a type 2 depositional sequence near the top of the formation. Organic debris associated with these highstand-systems-tract deposits is dominated by land-derived plant tissues. Marine influence is evidenced by the rare occurrence of dinoflagellate cysts, microforminiferal test linings, and the presence of gray, amorphous organic matter. Three palynofacies are recognized within highstand-systems-tract deposits in the upper Tuscahoma Sand based on the occurrence of organic debris. These palynofacies represent freshwater swamp, brackish marsh and marginal- to shallow-water marine depositional environments. Lignites in the Tuscahoma Sand are dominated by an angiosperm pollen assemblage. Gymnosperm pollen is rare, and marine forms are absent. This assemblage reflects deposition under fresh-water swamp conditions. Carbonaceous clay samples vary in the composition of organic debris. However, many are characterized by the occurrence of herbaceous angiosperm pollen. Arborescent angiosperm pollen is common, as are fern spores. Bisaccate conifer pollen is common and dinoflagellate cysts are rare. Fungal elements are abundant and woody tissue commonly is more degraded than in lignite samples. This assemblage represents deposition in coastal, brackish marsh environments. Organic debris in laminated clays, silts, and sands typically have angiosperm and gymnosperm pollen, dinoflagellate cysts, degraded terrestrial plant material, and amorphous organic matter, and represent shallow-marine and marginal-marine deposits.
- OSTI ID:
- 7136287
- Report Number(s):
- CONF-9310237-; CODEN: AABUD2
- Journal Information:
- AAPG Bulletin (American Association of Petroleum Geologists); (United States), Vol. 77:9; Conference: American Association of Petroleum Geologists (AAPG) mid-continent section meeting, Amarillo, TX (United States), 10-12 Oct 1993; ISSN 0149-1423
- Country of Publication:
- United States
- Language:
- English
Similar Records
Paleocene lignite deposits of southwest Alabama
Paleocene lignite deposits of southwest Alabama
Related Subjects
LIGNITE
PALEONTOLOGY
ORGANIC MATTER
DEPOSITION
ALABAMA
CLAYS
DINOFLAGELLATE
FOSSILS
FRESH WATER
GEOLOGIC DEPOSITS
MARLSTONE
MISSISSIPPI
PALYNOLOGY
PLANT TISSUES
POLLEN
SAND
SEDIMENTS
SILT
SPORES
TERTIARY PERIOD
ANIMALS
BODY
BROWN COAL
CARBONACEOUS MATERIALS
CENOZOIC ERA
COAL
DEVELOPED COUNTRIES
ENERGY SOURCES
FOSSIL FUELS
FUELS
GAMETES
GEOLOGIC AGES
GERM CELLS
HYDROGEN COMPOUNDS
INVERTEBRATES
MASTIGOPHORA
MATERIALS
MATTER
MICROORGANISMS
NORTH AMERICA
OXYGEN COMPOUNDS
PROTOZOA
TISSUES
USA
WATER
011000* - Coal
Lignite
& Peat- Reserves
Geology
& Exploration