Diverse melanges of an ancient subduction complex

Research Article| July 01, 1987 Diverse melanges of an ancient subduction complex Gary G. Lash Gary G. Lash 1Department of Geosciences, State University College, Fredonia New York 14063 Search for other works by this author on: GSW Google Scholar Author and Article Information Gary G. Lash 1Department of Geosciences, State University College, Fredonia New York 14063 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1987) 15 (7): 652–655. https://doi.org/10.1130/0091-7613(1987)15<652:DMOAAS>2.0.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Gary G. Lash; Diverse melanges of an ancient subduction complex. Geology 1987;; 15 (7): 652–655. doi: https://doi.org/10.1130/0091-7613(1987)15<652:DMOAAS>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Three lithologically and structurally diverse melanges occur within an early Paleozoic (Early–Middle Ordovician) subduction complex in the central Appalachian orogen. Type I melange, characterized by horizons of variably deformed sandstone and scaly mudstone that alternate with coherent sandstone-rich sequences, is interpreted to reflect accretion-related deformation of water-saturated trench deposits. Type II melange, composed of exotic radiolaria-bearing mudstone clasts in a scaly mudstone matrix, can be explained by remobilization and mixing of inner-trench slope sediments. Type III melange is a poorly sorted polymict assemblage of native lithology clasts in a scaly mudstone matrix. Evidence of forceful injection of matrix mud into clasts and inferred discordant contacts between melange and surrounding bedded deposits suggest that the type III melange formed from mud diapirism. The close association of these melanges points out the diversity of tectonic and sedimentary processes previously documented from modern convergent margins that may be reflected in older subduction complexes. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.