Research On The Comprehensive Evaluation Of Carboniferous Igneous Rock Reservoirs In Chepaizi And Hashan Area In Junggar Basin

The Igneous rock of Chepaizi and Hashan,Northwest Junggar Basin is a very important area for west exploration of Shengli Oil Field.At present,there are many problems of the exploration in igneous rock formations,such as lithological discrimination is hard,the electric character is complex and changeable,the identification of effective reservoir is difficult,and so on.With various methods like rock-mineral determination,analysis of X-ray elemental,analysis of X-ray diffraction minerals,and combining characteristics of igneous rock's elements and mineral composition.This paper summarized the physical characteristics of rock and the methods of lithological discrimination on igneous rock in the area of Chepaizi and Hashan.This paper researched the logging responses of igneous rock,explained the main influencing factors of electrical power,such as the components,pores,cracks,fluid,secondary changes,and by investigation on igneous rock's rock-electric and reason-analyzed on rock-electric inconformity positions,it found the rock-electric regularity: from the acid igneous rocks,the neutral igneous rocks to the base igneous rocks,the natural gamma value becomes smaller,the density log value gradually increases,the neutron log value becomes larger and the sonic lag value decreases.Using several methods such as experimental observation,rock ore appraisal,the casting thin sections,NMR logging,mechanical energy identification,especially the mechanical energy index which played a better role for rapid evaluation of reservoir physical property.This paper established the comprehensive evaluation standard about carboniferous igneous rock via a synthetical study on reservoir space,pore geometry,petrophysical property,fracture of igneous reservoir,which laid the foundation for later research and evaluation on igneous rock reservoir of Junggar Basin.