Paleographic and sedimentologic significance of Mississippian sequence at Mt. Darby, Wyoming
Mississippian strata at Mt. Darby comprise the Madison Group and the overlying Humbug Formation. This sequence, although initially transgressive, exhibits an overall regressive character produced by progradation of platform carbonates in response to sea level fluctuations related to Antler orogenic events. The Paine Member of the Lodgepole Limestone, the basal formation of the Madison Group, consists of relatively deep-water carbonates including a possible Waulsortian-type carbonate bank that accumulated on a Kinderhookian foreslope. At least five shoaling-upward grainstone cycles are recognizable in the Woodhurst Member of the Lodgepole Limestone. These cycles record Osagean deposition in shallow agitated environments that developed high on a clinoform ramp. Shelf-margin and platform carbonates dominate the Mission Canyon Limestone, the upper formation of the Madison Group. this unit consists of two asymmetric deposition cycles, each with a thick regressive phase, capped by an evaporite solution breccia and an overlying thin transgressive phase. The Humbug Formation, a sequence of fine-grained carbonates and sandstones, represents part of a deltaic complex that developed offshore from the Meramecian karst plain. Humbug sediments were transported northward to the Mt. Darby area from the area of the present Uinta Mountains, or another deltaic system formed there. Deposition in the study area was apparently continuous upward from the Madison carbonates into the Humbug. The middle Meramecian shoreline trended northwest between the present locations of Mt. Darby and Haystack Peak.
- Research Organization:
- Champlin Petroleum Co., Englewood, CO
- OSTI ID:
- 5992767
- Report Number(s):
- CONF-8506201-
- Journal Information:
- Am. Assoc. Pet. Geol., Bull.; (United States), Journal Name: Am. Assoc. Pet. Geol., Bull.; (United States) Vol. 69:5; ISSN AAPGB
- Country of Publication:
- United States
- Language:
- English
Similar Records
Mississippian and Pennsylvanian (Carboniferous) systems in the US - Wyoming
Stratigraphic sequence analysis of the Antler foreland
Related Subjects
020200* -- Petroleum-- Reserves
Geology
& Exploration
CARBONATE ROCKS
DEPOSITION
FEDERAL REGION VIII
GEOLOGIC AGES
GEOLOGIC FORMATIONS
GEOLOGIC HISTORY
GEOLOGIC STRUCTURES
LIMESTONE
MISSISSIPPIAN PERIOD
NORTH AMERICA
PALEOZOIC ERA
ROCKS
SANDSTONES
SEDIMENTARY ROCKS
SEDIMENTATION
USA
WYOMING