Geology, base-precious metal concentration and genesis of the silica-carbonate alteration (listwaenites) from late Cretaceous ophiolitic melanges at central east Turkey


Ucurum A., Larson L.

CHEMIE DER ERDE-GEOCHEMISTRY, vol.59, no.2, pp.77-104, 1999 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 59 Issue: 2
  • Publication Date: 1999
  • Title of Journal : CHEMIE DER ERDE-GEOCHEMISTRY
  • Page Numbers: pp.77-104

Abstract

The late Cretaceous (pre Maastrichtian) alteration of serpentinite bodies in the Divrigi and Kuluncak ophiolitic melanges has formed two distinct types of listwaenite. The earliest is silica-carbonate listwaenite (type I), which is dominated by silica + calcite + dolomite + ankerite +/- magnesite. Later, carbonate listwaenite (type II) comprise calcite + dolomite + ankerite + magnesite, and lack any significant introduced silica. Accessory ore minerals including pyrite, hematite, limonite, gersdorffite, marcasite, carrollite, langisite, and chromite are less abundant in carbonate listwaenite than they are in silica-carbonate listwaenite. Both types of listwaenite have been distinguished in the Guvenc and Karakuz areas, but in Curek only silica-carbonate has been recognized. The two listwaenite types are dissimilar in their major oxide and base-precious metal contents.