Search

The coalbed methane (CBM) resources in North China amounts up to 60% of total resources in China. North China is the most important CBM accumulation area in China. The coal beds of the Upper Paleozoic Taiyuan and Shanxi formations have a stable distribution. The coal reservoir of target areas such as Jincheng, Yanquan-Shouyang, Hancheng, Liulin, etc. have good CBM-bearing characteristics, high permeability and appropriate reservoir pressure, and these areas are the preferred target areas of CBM developing in China. The coal reservoirs of Wupu, Sanjiaobei, Lu'an, Xinmi, Anyang-Hebi, Jiaozuo, Xinggong and Huainan also have as good CBM-bearing characteristics, but the physical properties of coal reservoirs vary observably. So, further work should be taken to search for districts with high pressure, high permeability and good CBM-bearing characteristics. Crustal stresses have severe influence on the permeability of coal reservoirs in North China. From west to east, the crustal stress gradient increases, while the coal reservoirs permeability decreases.

This paper using sedimentology, organic petrology and geochemistry studies the oil-related, Early and Middle Jurassic terrestrial coal measures, Junggar and Turpan-Hami Basins, NW China, shows that: (1) the oil generated in the main generating stage is earlier and generates from fluorescent desmocollinite (desmocollinite B), bituminite, cutinite and suberinite; (2) the oil-generating models of some individual macerals and oil expulsion experiment of vitrain sample are given; (3) the new organic petrological oil-source correlation techniques using laser-induced fluorescence, CLSM (Confocal Laser Scanning Microscope) and TEM (Transmission Electron Microscope) parameters for oil-source correlation are expressed and (4) the sedimentary organic facies will be founded by sedimentary, organic petrological and organic geochemical parameters, of which the running water swamp/marsh facies is best concerned with coal measures related oil.

Using photometric and image analysis methods, a reasonable technique and procedure have been developed for the determination of maceral group composition and the reflectance of vitrinite. This procedure is introduced by an optimum method for seeking the interval values of each maceral group, i.e., from the “fingerprint” reflectance histogram, it seeks reasonable interval values and distribution values for vitrinite and other maceral groups. After checking and correction, these values can be put into a program and computerized. This method had advantages such as increased speed of analysis and reproducibility of the results.