Palaeozoic Reservoirs of Yenisei-Khatanga Basin
Anton Kusov, Konstantin Chebotar, Antonina Stoupakova, Tamara A. Kirjukhina, and Sergey Bordunov
Petroleum, Lomonosov Moscow State University, Moscow, Russia.
Yenisei - Khatanga basin is marked at the North-Western margin of Siberian Platform. Tectonically it holds borderline position: in the South the basin adjoins the platform structure - Tungusskaya syncline, and in the North - with Taimyr folding region. Basin’s current structural plan represents depression, which is filled by Jurassic-Cretaceous and Neogene-Quaternary complexes in the upper part.
Yenisei-Khatanga basin and Anabar-Khatanga saddle - large superorder structures. Along the surface of Riphean - Middle Paleozoic sediments Yenisei-Khatanga basin represents large asymmetric negative structure. According to structural plan the structures of the first order are marked along Upper Paleozoic - Quaternary sediments within the limits of superorder tectonic elements.
Studied territory is located within the limits of three oil-and-gas-bearing regions: Anabar-Khatanga, Yenisei-Khatanga and Anabar.
In order to study reservoir properties samples of Upper Paleozoic core from wells, drilled at the territory of Anabar-Khatanga and Yenisei-Khatanga regions have been selected. Selected samples represent sandstones, granular and silty to various extents. Rocks porosity, permeability and carbonate content were measured; microstructures were photographed using scanning electron microscope (SEM). Detailed micro description was made after analysis of lithological thin rock sections in incident light. Though majority of the selected samples do not refer to the most prospective intervals, mapped using well logging records, the reservoir properties of some chosen samples were determined as relatively good for this region.
On the Anabar anteclise’s Northern slope only two horizons can have relatively good potential for oil and gas: Riphean (Mukunskaya series) and Vendian - Lower Cambrian (Chaburskiy horizon) terrigene-carbonate horizons.
In Anabar-Khatanga oil-and-gas-bearing region’ only Upper Paleozoic sediments are characterized by regional oil-bearing capacity. The most potential reservoirs are sandstones of the Tustakhskaya formation (porosity from 4.9 to 21.3%, permeability varies from 0.1 to 61 m) and sandstones of the Nizhnekozhevnikovskaya formation (all samples had sufficiently high porosity 14.5 - 21.3% and low permeability 1.2 - 4.9 mD).
There are no any indications were found on the potential of Permian sediments in the Eastern part of Yenisei-Khatanga oil-and-gas-bearing region.
AAPG Search and Discover Article #90096©2009 AAPG 3-P Arctic Conference and Exhibition, Moscow, Russia