近日，中国地质大学Jian GAO团队研究了华北克拉通南部破坏及其与煤系页岩气富集的关系。相关论文发表在2025年9月18日出版的《中国科学：地球科学》杂志上。

华北克拉通南部煤系页岩气的生成机理和富集模式对深部能源勘探具有重要的指导意义。以华北克拉通南部淮北矿区为研究对象，通过盆地模拟、岩石热解、岩浆岩地球化学分析等方法，研究组系统揭示了华北克拉通破坏背景下煤系页岩气富集机制。研究表明，华北克拉通南部煤系在形成后主要发育了三期早白垩世岩浆活动（143–104?Ma）。其全岩地球化学特征显示弧型属性、指示俯冲板片熔融起源的埃达克岩亲和性，以及Sr-Nd同位素特征[（⁸⁷Sr/⁸⁶Sr）?=0.707–0.712，εNd(t)=−12.63至−9.18]表明，这些岩浆活动受控于西太平洋板块俯冲后撤作用，与华北克拉通破坏的构造背景相吻合。该热事件导致区域热流值升至130?毫瓦/平方米，显著加速了二叠纪煤系页岩的热演化进程。山西组和下石盒子组页岩的镜质体反射率（R₀）分别达到1.10%和1.33%，促进了重油热裂解成轻油和湿气，形成了页岩气的主要生烃阶段。

然而，克拉通的破坏也伴随着强烈的构造隆升；研究区累积侵蚀超过2000m。地层压力降低导致一些气体的解吸和逸出，突出了促进生烃和限制保存的双重作用。综合构造变形强度和岩浆活动时空分布特征，认为早白垩世岩浆活动叠加的构造变形弱区是页岩气富集的有利区。这些结果阐明了克拉通破坏下“热演化控制生成、构造活动控制保存”的页岩气成藏模式，对华北地区及其他类似背景复杂构造地区的页岩气勘探具有重要指导意义。

附：英文原文

Title: Destruction of the southern part of the North China Craton and its relationship with enrichment of shale gas in coal measures

Author: Peng WANG, Yiwen JU, Guofu LI, Shu JIANG, Jinchuan ZHANG, Lei XIAO, Wei WANG, Jian GAO

Issue&Volume: 2025/09/18

Abstract: The generation mechanism and enrichment patterns of shale gas in coal measure in the southern part of the North China Craton hold significant guiding implications for deep energy exploration. Taking the Huaibei mining area in the southern part of the North China Craton as the study object, this study systematically reveals the enrichment mechanism of shale gas in coal measure in the context of the destruction of the North China Craton through basin simulation, rock pyrolysis, and geochemical analyses of magmatic rocks. The results indicate that coal measures of the southern part of the North China Craton mainly developed three episodes of Early Cretaceous magmatism (143–104Ma) after their formation. Their whole-rock arc-type geochemical signatures, adakitic affinity indicative of subducted slab melting origins, and Sr-Nd isotopic characteristics [(87Sr/86Sr)i=0.707–0.712, εNd(t)=12.63 to 9.18] suggest they were controlled by the retreat of the subducting Western Pacific Plate, consistent with the background of North China Craton destruction. This thermal event caused the regional heat flow to surge to 130mWm2, significantly accelerating the thermal evolution of the Permian coal measure shales. The vitrinite reflectance (R) of shales in the Shanxi Formation and Lower Shihezi Formation reached 1.10% and 1.33%, respectively, promoting the thermal cracking of heavy oil into light oil and wet gas, forming the main hydrocarbon generation stage for shale gas. However, craton destruction was also accompanied by intense tectonic uplift; the cumulative erosion in the study area exceeded 2000m. Reduced formation pressure led to the desorption and escape of some gases, highlighting the dual effects of promoting hydrocarbon generation while limiting preservation. Integrating the intensity of structural deformation with the spatiotemporal distribution of magmatic activity, the study proposes that regions with weak structural deformation superimposed with Early Cretaceous magmatic intrusions represent favorable targets for shale gas enrichment. These results elucidate the shale gas accumulation model of “thermal evolution controlling generation and tectonic activity controlling preservation” under craton destruction, providing crucial guidance for shale gas exploration in the North China region and other complex structural areas with similar settings.

DOI: 10.1007/s11430-025-1655-0

Source: https://www.sciengine.com/SCES/doi/10.1007/s11430-025-1655-0