Reservoir-forming features of abiotic origin gas in Songliao Basin.

Autor: Guo, Zhanqian, Wang, Xianbin, Liu, Wenlong
Zdroj: Science in China. Series D: Earth Sciences; Dec1997, Vol. 40 Issue 6, p621-626, 6p
Abstrakt: The vertical structure of the crustal block of the Songliao Basin can be divided into upper, middle and low Earth’s crust according to density. There is an about 3-km-thick low density interval between the upper crust and the middle crust. This interval may be a magma chamber accumulated in crust by “fluid phase” which is precipitated and separated from upper mantle meltmass. The abiogenetic natural gas, other gaseous mass and hydrothermal fluids are provided to the Songliao rifted basin through crustal faults and natural earthquakes. This is a basic condition to form an abiogenetic gas reservoir in the Songliao Basin. On both flanks of the upper crust (or named basin basement) fault there are structural traps in and above the basement and unconformity surface or lateral extended sand, which contains communicated pores, as migration pathway and natural gas reservoir; up to gas reservoirs there is shale as enclosed cap rock, and the suitable arrangement of these conditions is the basic features of abiogenetic gas reservoir. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index