Green River iaminites: does the playa-lake model really invalidate the stratified-lake model

Journal Article · Tue Jun 01 04:00:00 EDT 1982 · Geology; (United States)

OSTI ID:6766263

Boyer, B W

Proponents of the playa-lake model have proposed deposition of most of the Green River Formation microlaminated carbonates (including oil shales) in lakes that were not perennially stratified (meromictic). However, there is a variety of evidence favoring a meromictic depositional environment: (1) close similarity of much of the lamination to varves in modern meromictic lakes, (2) evidence that hydrologic events favoring development of meromixis (chemical stratification) occurred prior to deposition of major accumulations of oil shale, (3) mutually exclusive distribution of fossil nekton (especially fish) and normal lacustrine benthos (including mollusks), and (4) analogy with a Quaternary playa that became a meromictic lake following increased inflow. The playa-lake model is untenable for the typical fish-bearing, kerogen-rich microlaminated sediments. These laminites were probably deposited in a large ectogenic meromictic lake - a chemically stratified lake that formed when increased fresh-water inflow ''drowned'' a saline playa complex.

• OSTI ID: 6766263
• Journal Information: Geology; (United States), Journal Name: Geology; (United States) Vol. 10:6; ISSN GLGYB
• Country of Publication: United States
• Language: English

Related Subjects

04 OIL SHALES AND TAR SANDS
040201* -- Oil Shales & Tar Sands-- Site Geology-- (-1989)
DEPOSITION
FEDERAL REGION VIII
FOSSILS
GEOLOGIC DEPOSITS
GEOLOGIC HISTORY
GEOLOGIC MODELS
GREEN RIVER FORMATION
MINERAL RESOURCES
NORTH AMERICA
OIL SHALE DEPOSITS
RESOURCES
USA
UTAH