Research progress of oil and gas resources in coal-bearing strata in North China and its implications

Abstract

The Carboniferous and Permian are important coal-bearing strata in North China， which develop various oil and gas resources such as coalbed methane， coal-bearing shale gas， tight coal-bearing sandstone gas， and coal-formed oil. Massive research and exploration results have shown that coal-bearing strata have good exploration prospects. Compared with those of the Ordos Basin， the exploration and research levels of the Carboniferous and Permian coal-bearing strata in Jiyang-Linqing area are relatively lower. The reservoir formation conditions of coal-bearing strata in Jiyang-Linqing area and Ordos Basin were comparatively analyzed， and the exploration directions for coal-bearing strata in Jiyang-Linqing area were proposed based on systematically summarizing the research progress of oil and gas resource types and enrichment conditions in coal-bearing strata in North China. The research results show that the coal-bearing strata in North China are mainly composed of Taiyuan Formation and Shanxi Formation， formed in the sedimentary environment of the epeiric sea delta. They have strong cyclicity and are developed into symbiotic coalbed methane reservoirs， coal-bearing shale gas reservoirs， and tight coal-bearing sandstone gas reservoirs. Coal， carbonaceous mudstones， and dark mudstones with high organic carbon content are the material basis for the formation of coal-bearing oil and gas resources， and coal-bearing source rock development areas with rich hydrogen have certain exploration potential for coal-formed oil. Preservation conditions are key factors for the enrichment of coalbed methane and coal-bearing shale gas. The high porosity and permeability zones caused by sedimentation and diagenesis are the sweet spot areas for tight coal-bearing sandstone gas. There are good exploration prospects for coal-bearing gas and coal-formed oil in Jiyang-Linqing area. Conducting a systematic evaluation by exploring a set of lithological combinations is an essential technical approach to improving the exploration efficiency of coal-bearing strata. The favorable exploration targets are Taiyuan Formation on the south slope of Dongying Sag and Huimin Sag， the western part of Chezhen Sag， and the Gubei buried hills.

Keywords

• coal-bearing strata
• three types of coal-bearing gas
• enrichment conditions
• jiyang-linqing area
• north china