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, cilt.59, ss.77-104, 1999 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 59 Konu: 2
  • Basım Tarihi: 1999
  • Dergi Adı: CHEMIE DER ERDE-GEOCHEMISTRY
  • Sayfa Sayıları: ss.77-104

Özet

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.