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Sediments of the Northern Middle America Trench

1971; Geological Society of America; Volume: 82; Issue: 2 Linguagem: Inglês

10.1130/0016-7606(1971)82[303

1943-2674

David A. Ross,

Paleontology and Stratigraphy of Fossils

Research Article| February 01, 1971 Sediments of the Northern Middle America Trench DAVID A ROSS DAVID A ROSS Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543 Search for other works by this author on: GSW Google Scholar GSA Bulletin (1971) 82 (2): 303–322. https://doi.org/10.1130/0016-7606(1971)82[303:SOTNMA]2.0.CO;2 Article history received: 27 Aug 1970 first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation DAVID A ROSS; Sediments of the Northern Middle America Trench. GSA Bulletin 1971;; 82 (2): 303–322. doi: https://doi.org/10.1130/0016-7606(1971)82[303:SOTNMA]2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search nav search search input Search input auto suggest search filter All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The Middle America Trench is a tectonically unstable area in which sediments have accumulated rapidly. Sediments from the upper part of the continental flank are folded and faulted within a perched basin and impounded by a ridge at the outer part of the basin. Little sediment accumulates permanently on the continental flank seaward of this basin. Sediments from the seaward flank have more biogenous material due to a lower rate of terrigenous deposition.Heavy minerals, coarse sands in the trench, facies similarities, displaced Foraminifera, and a textural gradation along the trench axis suggest that the sediments in the trench were deposited by turbidity currents. Carbon-14 dates indicate sedimentation rates as high as 146cm/1000 yrs in the trench bottom. Assuming constant conditions, the sediments found in the trench bottom would have taken only 4.5 × 106 yrs to accumulate. Sediment thicknesses vary along the trench axis but are consistent with present ideas of plate tectonics.Sedimentary facies of the Middle America Trench and the Gulf of California are similar due to the predominance of tectonic factors over depositional factors in these areas. In the Gulf of Mexico, the opposite is true, since the source regions have low relief and are subjected to stronger weathering. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not currently have access to this article.