Stream sediment geochemical exploration for gold in the Kazda dome in the Biga Peninsula, western Turkey

Yilmaz H.

TURKISH JOURNAL OF EARTH SCIENCES, vol.16, no.1, pp.33-55, 2007 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 16 Issue: 1
  • Publication Date: 2007
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, TR DİZİN (ULAKBİM)
  • Page Numbers: pp.33-55
  • Keywords: BLEG sampling, geochemistry, gold, mineral exploration, Kazdag, western Turkey, DRAINAGE GEOCHEMISTRY, COMPLEX
  • Dokuz Eylül University Affiliated: No


The Tuztasi Au-Ag mineralized system was discovered within the Kazdag dome using BLEG (bulk leach extractable gold) and 180-mu m stream sediment geochemical data collected across the Biga Peninsula in western Turkey. The deposit is located within the hinge of an antiform consisting mainly of high-grade metamorphic and melange rocks that include the Altinoluk Pb-Zn-Cu-Ag-Au and Evciler Fe-Au-Cu deposits on the southern and on the northern flanks, respectively; no mineralization has been reported prior to this work which was first carried out in 1996 between Altinoluk and Evciler. The BLEG Ag/Au ratios at Tuztasi (max 87) and Altinoluk (max 43) are very high to extremely high demonstrating the area to be relatively Ag-rich. This Ag enrichment is further demonstrated by rock chip Ag/Au ratios reaching up to 43 at the Tuztasi deposit. Silver is a moderate to very effective pathfinder for Au at Tuztasi. Arsenic is useful, being more mobile than Sb. Arsenic also constitutes the most coherent and the most significant geochemical anomaly in the northern half of the AYALE (Ayvacik-Altinova-Evciler) area which is underlain mainly by the melange rocks intruded by granitoid. The BLEG sampling accompanied by further follow-up 180-mu m stream-sediment sampling is a powerful technique in detecting Au-Ag deposits or occurrences. BLEG appears to be a time- and cost-efficient stream sediment geochemical technique for discovering relatively large primary geochemical halos encompassing the precious (Au, Ag) and base metal (Cu, Pb, Zn) deposits.