Research on the Reservoir Characteristics and Lithology Recognition based on Asphalt Sandstone

Abstract

Silurian lithology in tower is complex, and it is very difficult to identify with conventional logging data. Taking the 12 well areas in the Silurian tower as an example, reservoir characteristics were analyzed by thin slice, physical properties, oil washing, salt washing, asphalt washing, and litho-electrical experiments. On this basis, the logging data such as conventional logging, electro imaging, and ECS were combined by point-by-point matching, and the single well lithology recognition is carried out. The response characteristics of different lithology on logging curve are analyzed. The standard and plate of lithology recognition in the research area are established by means of the crossplot technique and discriminant analysis. The results show that the lithology of the study area is mainly rock debris sandstone and feldspar debris sandstone, and the reservoir is poor in physical properties. The asphalt is distributed in the detritus, miscellaneous matrix, colloidal particles and intergranular pores in three forms: oily asphalt, colloidal asphalt and asphalt asphalt. A standard sample was established based on various logging data, and the complex lithology recognition of Silurian system was identified by Fisher discriminant analysis method, which was verified and the compliance rate meets the requirements.