Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: oil-oil correlation

Sortuj według:

Ogranicz wyniki do:

Origin of liquid hydrocarbons accumulated in the Miocene strata of the Polish Carpathian Foredeep and its Palaeozoic–Mesozoic basement

Więcław D.

Annales Societatis Geologorum Poloniae

2011

Vol. 81, No 3

443-458

Petroleum geochemical data of 34 oils and condensates accumulated in the Carpathian Foredeep and its Mesozoic and Palaeozoic basement were used to assess their origin and genetic type. The analysed liquid hydrocarbons are characterized by variable densities and sulphur contents. No relationship between these parameters and the reservoir rock age has been found. Secondary processes of evaporative fractionation and biodegradation are evidenced for some oils. These processes proceeded most intensively on the oil from Góra Ropczycka-1K well. The oils from Opaka-1, Lubaczów-157 and Góra Ropczycka-1K wells were generated from organic matter deposited in the Upper Jurassic carbonates. The oil from the inflow in Załazie-2 well originated from the Cambrian strata, but also contains biomarkers characteristic of Miocene strata. The next family, genetically connected with the Silurian and Ordovician source rocks, consists of oils accumulated in the Lower Carboniferous carbonates in Nosówka deposit and in the Upper Jurassic in the inflow into Łękawica-1 well. The condensates collected from the Miocene (Łękawica-1, Pilzno-37, Tarnów-39 and -45 wells) and Upper Jurassic strata (Łąkta-27 and Tarnów-5 wells) were generated by organic matter dispersed in the Middle Jurassic or Lower Carboniferous clastic facies. The remaining oils, from Grobla-Pławowice, Wierzchosławice, Jastrząbka Stara, Partynia-Podborze, Dąbrowa Tarnowska, Brzezówka and Zagorzyce deposits, and the inflows into Tarnów-47 and Pilzno-12 wells were generated from kerogen enriched in organic sulphur usually dispersed in carbonate rocks. Such a type of sediments occurs in the Devonian and Lower Carboniferous strata. Also, these strata as well as the underlying Silurian rocks have sufficient maturity for generation of the discussed oils. The oleanane in the discussed oils most probably originates from kerogen of the Upper Cretaceous or Miocene strata, through which these oils migrated and eluted this biomarker.

Origin of oils accumulated in the Middle Cambrian reservoirs of the Polish part of the Baltic region

Kowalski A., Więcław D., Kotarba M. J.

Geological Quarterly

2010

Vol. 54, No 2

205-216

We have examined 21 samples of crude oils accumulated in the Middle Cambrian sandstone reservoirs from the Polish part of the Baltic region. All the crude oils have similar parameters and indices, which suggests generation from the same source rock. Evaporative fractionation and biodegradation processes were detected in oil collected from the B4-N1/01 borehole. All crude oils have high gravities and low-sulphur contents, less than 0.3 wt.%, which suggests that their source rock contained low-sulphur kerogen deposited in a clastic environment. A low asphaltenes content (below 0.3 wt.%) and high saturate/aromatic hydrocarbon ratios indicate long migration distances or high thermal maturities. The longest migration distance was probably attained by oils from the arnowiec and B16 deposits. The biomarker data indicate an algal origin for the source organic matter deposited under conditions of clastic sedimentation. The stable carbon isotope data support this observation. The maturity of the oils analysed varies from ca. 0.75 to ca. 1.05% on the vitrinite reflectance scale. Unlike the B6, B16, Dbki and arnowiec accumulations, oils from the B3 and B4 accumulations reveal the lowest maturity.