Eyles, Nicholas et al. (1999): Ocean Drilling Program Leg 178 (Antarctic Peninsula); sedimentology of glacially-influenced continental shelf "topsets" and "foresets"
Leg/Site/Hole:
Related Expeditions:
ODP 178
Identifier:
ID:
2001-006844
Type:
georefid
Creator:
Name:
Eyles, Nicholas
Affiliation:
University of Toronto at Scarborough, Environmental Earth Sciences, Scarborough, ON, Canada
Role:
author
Name:
Daniels, James
Affiliation:
University of Melbourne, Australia
Role:
author
Name:
Osterman, Lisa E.
Affiliation:
Smithsonian Institution, United States
Role:
author
Name:
Januszczak, Nicole
Affiliation:
Role:
author
Identification:
Title:
Ocean Drilling Program Leg 178 (Antarctic Peninsula); sedimentology of glacially-influenced continental shelf "topsets" and "foresets"
Year:
1999
Source:
In: Anonymous, Geological Society of America, 1999 annual meeting
Publisher:
Geological Society of America (GSA), Boulder, CO, United States
Volume:
31
Issue:
7
Pages:
56
Abstract:
The glacially-influenced Cenozoic continental margin of Antarctica has a large-scale internal structure that consists of flat-lying "topsets" recording episodic aggradation of the continental shelf, resting on seaward-dipping, wedge-shaped "foresets" formed by the progradation of the continental slope. Ocean Drilling Program Leg 178 (February-April 1998) drilled two sites (1097, 1103) through the outer Antarctic Peninsula Pacific continental shelf into strata no older than late Miocene or early Pliocene (<4.6 Ma). Site 1097 lies on the outer shelf and reached a maximum depth drilled of 420 m below the sea floor (mbsf). Strata consist of thick intervals of massive diamictite, containing large amounts of reworked and abraded marine microfauna, interpreted as tills produced by subglacial re-working of marine sediments. Tills are separated by bioturbated muds with dropstones and contain a diverse in situ fauna. The sedimentary record at Site 1097 is consistent with aggradation of a "topset" by till deposition alternating with open marine sedimentation. Site 1103, close to the shelf edge, reached a depth of 363 mbsf through massive and chaotically-stratified diamictites with graded siltstones consistent with deposition on a slope "foreset" and progradation of the continental slope by deposition of debrites and turbidites.
Language:
English
Genre:
Rights:
URL:
Coverage: Geographic coordinates: North:-63.0000 West:-77.3000 East:
-56.3000 South:-77.0000
Keywords: Stratigraphy; Sedimentary petrology; aggradation; Antarctic Peninsula; Antarctica; argillite; biogenic structures; bioturbation; Cenozoic; clastic rocks; clastic sediments; continental margin; continental shelf; debrite; deposition; depositional environment; diamictite; glacial environment; Leg 178; lower Pliocene; marine environment; marine sediments; Miocene; mud; Neogene; Ocean Drilling Program; ODP Site 1097; ODP Site 1103; Pliocene; progradation; sedimentary rocks; sedimentary structures; sediments; stratification; Tertiary; thickness; till; turbidite; upper Miocene;
.