催化加氢热解法在南丹大厂古油藏固体沥青油源研究中的应用

广西南丹大厂中泥盆统古油藏固体沥青及其潜在烃源岩——同区泥盆系深水槽盆地相优质泥岩均已达到过成熟热演化阶段,其沥青“A”含量均很低,并且强烈的热改造作用和后期抬升接近地表后可能发生的生物降解作用,严重影响了用沥青“A”中常规生物标志物进行油源研究的准确性.目前固体沥青的来源缺乏直接的分子有机地球化学证据.本文运用了催化...

Application of catalytic hydropyrolysis in solid bitumen-source correlation of the paleo-oil reservoirs in Nandan area

The Dachang Middle-Devonian solid bitumen and its potential source rock,Devonian mudstone of trough facies in the Nandan area,south China,are all at over-mature stage.Low concentration of extractable organic matter,intense thermal alterations,and sever biodegradation may obscure the oil-source correlations based on routine biomarkers.Thus,direct molecular geochemical evidences are absent in most bitumen-source correlation studies.Catalytic hydropyrolysis is a new approach that can release biomarkers from highly mature kerogen and solid bitumen.It shows the advantages to maximize the yields of covalently-bound biomarkers from kerogen,to minimize structural rearrangement of biomarker species,and to maintain the biologically-inherited stereochemistry.In the research,the covalently-bound biomarkers and n-alkanes released from the Middle-Devonian solid bitumen and two kerogens of the potential Devonian mudstone of trough facies in the Nanpanjiang Depression by catalytic hydropyrolsis were analyzed for GC-MS and GC-IRMS to clarify the origin of organic matter in the paleo-oil reservoirs.The results indicated that the Devonian mudstone of trough facies probably were the main source for the Dachang Middle-Devonian solid bitumen in Nandan area.