Earth  Sciences
Jinxing Dai

Coal-derived gas theory and its discrimination

Abstract:He demonstrated the basic rule of hydrocarbon generation and established a complete coal-derived gas theory, i.e., during the whole coalification process from low rank to high rank coals, the hydrocarbon generation is dominated by gas and supplemented by oil, with a small amount of light oil and condensate oil at medium rank coal stage. This breaks through the conventional conception that coal measure is not good gas source rock, which leads to the finding of a number of giant gas fields and make China change from gas-poor to gas-rich country.

He improved the gas origin discrimination system. He integrated the gas-liquid (light hydrocarbon and oil)-solid (kerogen) information and established a gas origin discrimination theory for coal-derived, oil-derived and abiogenic gases with a series of parameters, figures and formulas. This provides a set of reliable and high-precision discrimination method for gas origin under the complicated geological condition.

He discovered the central Asian and eastern Asian coal-derived gas accumulation zones and the large zonal and continental distribution of source rocks of coal-derived gas in the zone. Due to the similar distribution and accumulation pattern of gas fields, similar reservoir formation condition and similar gas origin, we can predict the undiscovered gas enrichment areas in the zone based on the features of discovered gas enrichment areas. A number of giant gas fields have been scientifically predicted in the above zones.

Awardee:Prof. Jinxing Dai was born in the Rui’an County, Zhejiang Province, China in March, 1935. He is a geologist and a geochemist and is also a member of Chinese Academy of Sciences. He was graduated from the Geology Department of Nanjing University in 1961. From 1961 to 1962, Prof. Dai was engaged in the geological research of oil and gas in the Research Institute of Petroleum of the Ministry of Petroleum Industry. From 1962 to 1972, Prof. Dai took up research work on petroleum exploration in the Jianghan Oilfield in the Hubei Province. Since June in 1972, he has carried out the geological and geochemical research on natural gas in the Research Institute of Petroleum Exploration and Development, PetroChina. He was a member of the fourth Academic Degrees Committee of the State Council. From 1983 to 1998, Prof. Dai continuously served as a chief or deputy project director of the "Sixth-five" (65-18), "seventh-five" (75-54), "eighth-five" (85-102) and "ninth-five" (96-110) National Key Science and Technology Project of National Gas. He leaded and organized the national natural gas research and provided scientific support to promote the development of natural gas exploration, which opened the new exploration field of coal-derived gas and provided theoretical support for China changing from gas-poor country to gas-rich country.

He made significant contributions to the establishment and development of coal-derived gas theory, discovery that hydrocarbons generated from coal measures were dominated by gas, with subordinate amounts of oil, discrimination of natural gases of various origins, abiogenic gas and its formation conditions, formation, controlling factors and favorable area prediction of medium to large gas fields. Prof. Dai scientifically predicted 7 giant gas fields with reserves more than 1 1011 m3 about 4-15 years in advance.

Prof. Dai won the Advanced Individual Award of National Key Science and Technology Project three times in 1986, 1991 and 1996, respectively, First Prize of the State Science and Technology Progress twice in 1987 and 1997 (both as the first important contributor), Second prize of the State Natural Science Award (first author). In 2001, Prof. Dai won the Science and Technology Award of the Ho Leung Ho Lee Foundation. At present, Prof. Dai holds the position of the chief editor of Petroleum Exploration and Development, and Natural Gas Geoscience (both Chinese and English version). Prof. Dai published 180 first-authored scientific papers, and 28 scientific books (first author or only author). He has fostered 53 students, including those who became academician of Chinese Academy of Sciences and National Distinguished Young Scholar.