Baranov V.A.,Orlova T.V.,Kirichenko V.А. M.Sc. Influence of sandstone structural parameters on gas content and gas permeability

Details

Parent Category: Geo-Technical Mechanics, 2017

Category: Geo-Technical Mechanics, 2017, Issue 136

Geoteh. meh. 2017, 136, 34-41

INFLUENCE OF SANDSTONE STRUCTURAL PARAMETERS ON GAS CONTENT AND GAS PERMEABILITY

¹Baranov V.A., ¹Orlova T.V., ²Kirichenko V.А. M.Sc.
¹IGTM NAS of Ukraine, ²INME NAS of Ukraine

UDC 551.14:553.21

Abstract. Annotation. Subject of research is carbonaceous sandstones of the Donetsk coal basin. Objective of the work is to study and analyze influence of structural parameters of sandstones - main hydrocarbon reservoirs - on their gas content and gas permeability. The analysis was carried out for different conditions of formation and transformation of sandstones containing coals of different stages of coalification. The studies were carried out on standard sections with using optical microscopy. The grits were made of sandstone samples taken from the faces of coal mines or of the coretaken from exploratory wells. As a result of the research, it was established that calcite cement, with other equal conditions, is the most unfavorable factor affecting porosity and filtration properties. While forecasting gas content in the rocks, it is necessary to take into account content of precisely secondary, recrystallized forms of carbonates, since this process is accompanied by a significant deterioration of the sandstone filtration characteristics. The most favorable, in terms of reservoirproperties, will be rocks with clay cement. A minor admixture of primary carbonate (within 5-6%) insignificantly affect the properties of the rocks under consideration. Coarse-grained rocks will have favorable reservoir properties in the upper parts of the stratigraphic horizons located at the stage of early and, partially, middle katagenesis. Sandstones with a higher degree of sorting and rounding, in which fine- and medium-grained fractions of clastic grains predominate, are characterized by higher reservoir capacity and greater productivity. Values of the microreflection coefficient increase with increase of grain size, deterioration of sorting, increase in the paleo depth and tectonic stresses and reduction of cement; therefore, this index indirectly reflects reservoir properties of the sandstone. The most productive, in terms of reservoir properties, are intervals of the subsoil part of the rock layer, which are at the stage of early and medium katagenesis. For most of the Donbass rocks, the katagenesis processes of mineral and sandstone cement transformation are characteristic for the closed system. This was the main reason for formation of such low gas permeability of the Donbass rocks.
Keywords: Keywords: structure transformation, sandstones, katagenesis, gas content.

REFERENCES

1. Murich, A.T. (1990), “On the gas-oil-gas content of coal-bearing basins (on the example of Donbass), Resursy netraditsionnogo gazovogo syrya i problem ego osvoeniya, VNIGRI, Leningrad, p. 93-97.
2. Baranov, V.A. (2000), ―Structural changes sandstones of Donbas and the forecast of their outburst, Abstract of D.Sc. dissertation, Geology of solid fuels, National Mining Academy of Ukraine, Dnepropetrovsk, Ukraine.
3. Hays, P.D., and Grossman, E.L. (1991), ―Oxygen isotopes in meteoric calcite cements as indicators of continental paleoclimate, Geology, v. 19, p. 441-444.
4. Kim, J.C., Lee, Y.I., and Hisada, K.I. (2007), ―Depositional and compositional controls on sandstone diagenesis, the Tetori Group (Middle Jurassic-Early Cretaceous), central Japan", Sedimentary Geology, v. 195, p. 183-202.
5. Lundegard, P.D. (1992), ―Sandstone Porosity Loss - A "Big Picture" View of The Importance of Compaction, Journal of Sedimentary Petrology, v. 62, p. 250- 260.
6. Moore, C.H. (2001), Carbonate Reservoirs Porosity Evolution and Diagenesis in a Sequence Stratigraphic Framework, Developments in Sedimentology 55: Amsterdam, Elsevier Science B.V., p. 245-287.

 About the authors:

Baranov Vladimir Andreevich, Doctor of Geology (D.Sc.), Senior Researcher, Head of Laboratory, Institute of Geotechnical Mechanics name by N. Polyakov of National Academy of Sciences of Ukraine (IGTM, NASU), Dnepr, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. .

Orlova Tatyana Viktorovna, Doctoral Student, Institute of Geotechnical Mechanics name by N. Polyakov of National Academy of Sciences of Ukraine (IGTM, NASU), Dnepr, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. .

Kirichenko Victoria Anatolyevna, Chief Geologist, Department of Anthropogenic Changes in the Geological Environment, Institute of Nature Management and Ecology of National Academy of Sciences of Ukraine (INME NAS of Ukraine), Dnepr, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.

• < Prev
• Next >