The effect of ductile-lithic sand grains, overpressure and secondary dissolution on porosity and permeability and their relevance to hydrocarbon exploration in Askale sub-basin, East Anatolia, Turkey


Bueyuekutku A., Sahintuerk O.

ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS, cilt.28, sa.11, ss.1027-1038, 2006 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 28 Sayı: 11
  • Basım Tarihi: 2006
  • Doi Numarası: 10.1080/009083190957595
  • Dergi Adı: ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.1027-1038
  • Anahtar Kelimeler: diagenesis, ductile lithic grain, overpressure, geothermal gradient, permeability, porosity, hydrocarbon, Askale sub-basin, East Anatolia Basin, Turkey, COMPACTION, GRAYWACKE, SANDSTONE, MODEL
  • Ankara Üniversitesi Adresli: Evet

Özet

Ductile lithic grain, secondary porosity, temperature, and overpressure control porosity and permeability in the Mio-Pliocene and Upper Oligocene sandstones of the Askale sub-basin in East Anatolia. Ductile lithic grains account for between approximately 60-90% of the original sand grain population. There is a pronounced loss of porosity with increasing bruial depth in this sub-basin. At depths of less than 3000 m, this is due solely to ductile-lithic grain compaction where the rate of porosity loss of with depth increases with increasing ductile-lithic grain content. But at depths greater than 3000 m, the steep porosity increases with depth due to secondary solution activities and overpressure in the Askale sub-basin in East Anatolia. Secondary porosity is a common diagenetic feature in the more deeply buried (>3000 m) sediments in the Askale sub-basin. The secondary porosity arises principally from dissolution of feldspar, to a lesser extent, of the quartz (approximately 10-30%). Overpressure is due to tectonic stress. Reservoir quality is thus controlled by secondary solution activities, overpressure, temperature (geothermal gradient) and depth of burial in the Askale sub-basin in East Anatolia Basin.