云南禄劝残植煤的有机地球化学特征及其石油地质意义

Organic geochemistry and hydrocarbon potential of liptobiolite in Luquan,Yunnan Province

禄劝煤是我国典型的残植煤,是泥盆系煤岩的代表。研究其生烃能力有助于认识中国南方泥盆系煤系的油气资源前景。通过对禄劝煤和泥灰岩有机岩石学、有机地球化学特征的分析,发现禄劝煤具有Ⅱ型有机质的特征,角质体为特征组分,类脂组含量高,处于低熟阶段,氯仿沥青"A"和总烃含量高。热解生烃实验证明其具有较窄的活化能分布范围且较低,其值为201kJ/mol,其生烃潜力为820.0mg/g,明显高于常见的泥质烃源岩。尽管禄劝煤系规模小、煤层厚度薄,但其具有良好的生烃能力,这对认识泥盆系煤层及其相关烃源岩岩系有重要意义。

The Devonian coal in Luquan, Yunnan Province, is a typical liptobiolite in China. The study on its hydrocarbon potential will facilitate the understanding of the exploration prospect of the Devonian coals in South China. Based on the studies of organic petrology, organic geochemistry and pyrogenation experiments, it is found that cutinite is the dominant maceral and that liptobiolite is the characteristic maceral. The kerogen in Luquan liptobiolite belongs to kerogen of type Ⅱ, and presents low maturity and high concentration of bitumen and hydrocarbon. Pyrogenafion experiments indicate that the coal has high hydrocarbon production with narrow and low kinetic activation energies, about 201 kJ/mole. It has high hydrocarbon potential, about 820.0 mg/g. Although the distribution and thickness of Luquan coal are limited in southern China, this study highlights the petroleum prospect of the Devonian coals and the related rocks.