煤成烃差异性研究

Huge gas reserves have been found in Ordos basin, Kuqa depression of Tarim basin and western Sichuan basin which were generated from the Carboniferous-Permian, Jurassic and Upper Triassic coal measures, respectively. However, substantially lower amount of gas hydrocarbons have been found which were generated from coal measures within the Lower Jurassic Badaowan Formation and Middle Jurassic Xishanyao Formation in the southern areas of Junggar basin. In this application, Programing confined pyrolysis (gold capsules) experiments will be performed on a large number coal and kerogen samples from the coal measures within the Lower Jurassic Badaowan Formation and Middle Jurassic Xishanyao Formation in Junggar basin, Jurassic strata of Quka depression of Tarim basin, and the first, 3th and 5th sections of Upper Triassic Xijiahe Formation in western Sichuan basin. Kinetic parameters for oil and gas generations will determined, and oil and gas yields and conversion values for oil and gas generations especially at maturity Ro%<1.3 will be obtained for these coal measures from these experiments. The results of these experiments will exhibit the differences in kinetic parameters, oil and gas yields and conversion values for oil and gas generations at various maturities among these coal measures, and provide solid data for hydrocarbon potential evaluation and exploration in the three basins.

我国对鄂尔多斯盆地石炭－二叠系、塔里木盆地库车坳陷侏罗系和四川盆地上三叠统须家河组煤成气的勘探取得巨大成就，然而，对准噶尔盆地南缘中－下侏罗统煤成气的勘探与上述三个地区具有很大反差。本项申请拟通过金管－高压釜实验装置对准噶尔盆地下侏罗统八道湾组、中侏罗统西山窑组、塔里木盆地库车坳陷侏罗系和四川盆地上三叠统须1、须3和须5段的煤岩和暗色泥岩进行大量样品的生烃动力学模拟实验，求取生油、生气动力学参数和中－低演化阶段Ro%<1.3的生油、生气量和转化率。揭示三个地区煤系烃源岩生烃动力学特征、生烃量和各热演化阶段生烃转化率的差异性，并为三个地区煤成烃资源评价和勘探提供可靠的基础数据。

含煤盆地煤成油和煤成气勘探潜力差异很大，研究煤生烃潜力和生烃动力学对油气勘探具有重要意义。本项目应用金管－高压釜实验技术对准噶尔盆地南缘侏罗系12个煤样、库车坳陷三叠－侏罗系7个煤样和川西上三叠统3个煤样进行生烃动力学模拟实验，求取煤样的生油、生气量和生烃动力学参数。准噶尔盆地南缘12个煤样最大累积生油量和生气量分别介于60–209 mg/g TOC和91–185 mg/g TOC之间，达到排气门限(20 mg/g TOC)时的成熟度介于EASY%Ro 1.36–1.50之间。生油频率因子介于9.16×1012 s-1 –1.58×1013 s-1之间，生油活化能加权平均值介于50.65–51.93 kcal/mol之间；生气频率因子介于7.47×1013 s-1–1.91×1014 s-1之间，生气活化能加权平均值介于61.70–63.98 kcal/mol之间。塔里木盆地库车坳陷7个煤样最大累积生油量和生气量分别介于14–83 mg/g TOC和70–121 mg/g TOC之间，达到排气门限时的成熟度介于EASY%Ro 1.59–1.76之间。生油频率因子介于9.61×1012 s-1 –1.69×1013 s-1之间，生油活化能加权平均值介于51.64–52.96 kcal/mol之间；生气频率因子介于9.21×1013 s-1–1.67×1014 s-1之间，生气活化能加权平均值介于62.78–65.33 kcal/mol之间。川西3个煤样最大生气量介于123–162 mg/g TOC之间，达到排气门限时的成熟度介于EASY%Ro 1.38–1.53之间。生气频率因子介于9.16×1013 s-1–1.58×1014 s-1之间，生气活化能加权平均值介于63.86–65.01 kcal/mol之间。