Depositional Environment and Origin of Inertinite-rich Coal in the Ordos Basin  

作　　者：SHI Qingmin ZHAO Jun JI Ruijun XUE Weifeng HAN Bo CAI Yue LI Chunhao CUI Shidong 

机构地区：[1]College of Geology and Environment,Xi’an University of Science and Technology,Xi’an 710054,China [2]Shaanxi Coal Chemical Industry Technology Research Institute Co.,Ltd.,Xi’an 710199,China [3]China National Logging Corporation,Geological Research Institute,Xi’an 710077,China

出　　处：《Acta Geologica Sinica(English Edition)》2024年第4期1064-1085,共22页地质学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Grant No.42272209);the Natural Science Basic Research Program of Shaanxi(Grant No.2021JLM-12);the CNPC Major Science and Technology Project(Grant No.2021DJ3805)。

摘　　要：Inertinite-rich coal is widely distributed in the Ordos Basin,represented by the No.2 coal seam of the Middle Jurassic Yan'an Formation.This paper combined coal petrology and geochemistry to analyze the origin of inertinite,changes in the coal-forming environment and control characteristics of wildfire.Research has shown that there are two forms of inertinite sources in the study area.Alongside typical fusinization,wildfire events also play a substantial role in inertinite formation.There are significant fluctuations in the coal-forming environment of samples at different depths.Coal samples were formed in dry forest swamp with low water levels and strong oxidation,which have a high inertinite content,and the samples formed in wet forest swamp and limnic showed low inertinite content.Conversely,the inertinite content of different origins does not fully correspond to the depositional environment characterized by dryness and oxidation.Nonpyrogenic inertinites were significantly influenced by climatic conditions,while pyrofusinite was not entirely controlled by climatic conditions but rather directly impacted by wildfire events.The high oxygen level was the main factor causing widespread wildfire events.Overall,the combination of wildfire activity and oxidation generates a high content of inertinite in the Middle Jurassic coal of the Ordos Basin.

关 键 词：inertinite-rich coal WILDFIRE coal petrology geochemistry biomarkers depositional environment 

分 类 号：P618.11[天文地球—矿床学]