Abstract:

The reservoir characteristics including lithology, lithofacies, pore type of the Carboniferous volcanic rocks in the 6th，the 7th and the 9th areas of Karamay oil field are analyzed based upon core observation, thin section identification, scanning electron microscope analysis and well logging interpretation. The reservoir pore space types, relationship between the reservoir spaces and flowing passageway and main parameters affecting the reservoir quality are also studied. The results indicate that the major rocks are lava which includes basalt and andesite, pyroclastics and pyroclastic sedimentary which includes volcanic breccia, tuff and sedimentary tuff. Three types of reservoir spaces including vesicles, pores and fractures can be classified based on the pore structures, and the primary and secondary pores can be identified based upon origin. The major controlling parameters for reservoir quality are petrology, lithofacies and tectonic action as well as weathering and leaching processes.

Key words: reservoir pore space, controlling factor, Carboniferous, volcanic rocks；Karamay oil field