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Title: Mineralogical and geochemical evidence of Quachita provenance

Provenance of the extremely thick Ouachita flysch has not been specifically identified, despite several recent studies. Detrital mineral compositions, Sm-Nd model ages, and single zircon dates strongly suggest that several sources contributed sediment that became well-mixed before deposition. Sm-Nd model ages are nearly uniform for flysch samples, regardless of geographic position or exact stratigraphic position. These ages appear to rule out significant contribution by a Paleozoic island arc, and suggest a single source, multiple sources with similar model ages, or thorough mixing of sources with different model ages. In contrast, single zircon ages are variable, including Archean, Proterozoic, and Paleozoic ages. These ages indicate multiple sediment sources, including some external to North America. The zircon ages, however, may not be generally representative of Ouachita sediment sources because they were obtained on zircons far larger than typical Ouachita detrital zircons. The Sm-Nd model ages and single zircon ages can both be explained if sediment entering the Ouachita Trough came from multiple sources, but was already thoroughly mixed before entering the trough. Such mixing is also suggested by detrital mineral analyses. Muscovite, garnet, and tourmaline have been analyzed.
Authors:
 [1] ; ;  [2] ;  [3]
  1. (Colorado State Univ., Fort Collins, CO (United States). Dept. of Earth Resources)
  2. (Univ. of Texas, Austin, TX (United States). Dept. of Geological Science)
  3. (Univ. of Manchester (United Kingdom). Dept. of Geology)
Publication Date:
OSTI Identifier:
6785964
Report Number(s):
CONF-9404221--
Journal ID: ISSN 0016-7592; CODEN: GAAPBC
Resource Type:
Conference
Resource Relation:
Journal Name: Geological Society of America, Abstracts with Programs; (United States); Journal Volume: 26:4; Conference: 43. annual meeting of the Southeastern Section of the Geological Society of America, Blacksburg, VA (United States), 7-8 Apr 1994
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; ARKANSAS; GEOLOGIC FORMATIONS; GEOCHEMISTRY; ISOTOPE DATING; MINERALOGY; PETROGENESIS; SEDIMENTARY ROCKS; ISOTOPE RATIO; NEODYMIUM ISOTOPES; SAMARIUM ISOTOPES; AGE ESTIMATION; CHEMISTRY; DEVELOPED COUNTRIES; GEOLOGY; ISOTOPES; NORTH AMERICA; PETROLOGY; RARE EARTH ISOTOPES; ROCKS; USA 580000* -- Geosciences