000 03126nab a2200253 4500
005 20260520002141.0
008 260224s2018 xxu ing
041 _aInglés
245 0 0 _aEocene and oligo-miocene source rocks in the Rioni and Kura basin of Georgia
_bDepositional environment and petroleum potential
260 _a
_b
_cjul. 2018
270 _a22/01/2019 ; 22/01/2019
300 _a25 p. ; 367-392
520 _aTranscripción del resumen del autor: For over a century, oil has been produced in Georgia from oilfields located in the foreland basins between the Greater and Lesser Caucasus foldbelts. To date, little information on the associated source rocks has been available. In this context, this paper presents a study of 380 samples of Eocene (Kuma Formation) and Oligocene to Lower Miocene (Maikop Group) source rocks from three outcrop sections in the Rioni and Kura Basins. The Kuma Formation in the Rioni Basin is composed of fully-marine marls and is about 40 m thick. At the Martivili and Khobi sections, the formation is thermally immature and has an average TOC of 3.2 wt%. The hydrogen indices (HI) of 300–600 mg HC/g TOC indicate that the organic matter is oil-prone Type II kerogen. The oil generation potential is between 1.0 and 2.4 t HC/m2, and the Kuma Formation is therefore interpreted as a prolific source rock. The Maikop Group in the Rioni Basin was studied at the Martvili section, where it is thermally immature. The Oligocene succession is divided by calcareous shales deposited during the Solenovian Event (at the onset of nannoplankton zone NP23) into Pshekhian and Solenovian-to-Kalmykian intervals. The Pshekhian interval (NP21-22) is over 60 m thick and comprises a marly lower part and a shale-rich upper part, and contains high quantities (average 2.7 wt% TOC) of Type II-III kerogen (average HI: 278 mg HC/g TOC). The overlying largely carbonate-free shale succession, 424 m thick, is less organic matter -rich (~2.0 %TOC) and contains dominantly Type III kerogen (average HI: 140 mg HC/g TOC). In total, the Maikop Group has a generation potential of about 4 t HC/m2, a value which is higher than in most other sub-basins in the Eastern Paratethys. Because the Rioni Basin continues westwards into the Black Sea, these results are relevant for future exploration in the eastern part of the Black Sea Basin. The Maikop Group in the western Kura Basin in the Tbilisi area is over 3500 m thick and includes numerous sandstone beds. Because of the great thickness of the Maikop Group and the presence of about 3 km of overburden, which was removed during Miocene to Recent unroofing, potential source rocks in the Eocene to Lower Oligocene succession have reached oil window maturities but their hydrocarbon potential is low.
581 _a3
773 0 _tJournal of Petroleum Geology
_g
942 _cARTICULO
100 1 _aPupp, M.
_958233
100 1 _aBechtel, A.
_951164
100 1 _aCóric, S.
_958253
100 1 _aGratzer, R.
_958237
100 1 _aRustamov, J.
_958254
100 1 _aSachsenhofer, R.F.
_951162
999 _c192379
_d192379