Rockphysics Modeling And Gas Reservoir Detection Of TaiNan-SeBei Gas Field In The Tsaidam Basin

The Tsaidam Basin, the biggest Mesozoic continental sedimentary basin in the northeast of Qinghai-Tibet Plateau, is the world's highest oil and gas bearing basin in altitude. Being one important region included in our country's Energy Strategy, it has unique geographical position, complicated structure, rich oil gas resources and other traits. The quaternary biogas reservoir in Sanhu, located in east Tsaidam Basin, is currently the largest area where biogas has been found in quaternary system all over the world.Seismic rock physics, known as the"bridge"connecting seismic data and reservoir attributes, is a science composed of traditional rock physics and exploration seismology. The object of this science is to associate reservoir rocks and its pore fluid with seismic attribute. Through the application of system theory and medium model on various physical properties, such as rock elastic, viscoelasticity, and anisotropism, connections between seismic attribute parameters and reservoir attribute parameters are to be built. And via some technical means, such as fluids replacement and prestack inversion, the basis for explanation of subtle reservoir, remaining oil mining and monitoring, as well as other seismic data is provided, thus to greatly advance the development of seismic lithological discrimination, reservoir fluid test, oil reservoir seismic monitoring and so on.This paper studies the rock physical properties of quaternary lacustrine facies sand shale in Sanhu area, Tsaidam Basin, and also analyzes reservoir identification features of different stratum. Links between oil reservoirs attribute parameters and seismic attribute parameters are established by s-wave prediction, fluids replacement or other techniques. Based on the petrophysical analysis, purposeful prestack inversion research is conducted, and then prediction of high gas-content saturation reservoir is realized.