Abstract: 54 soil-gas samples were collected from three hidden faults which are considerable differentin fault movement and seismicity in the northern part of North China. The results indicate thatthere are notable anomalies in H₂ on Tangshan and Xiadian hidden active faults,but no anomalyon Xianhe-Huangzhuang hidden inactive fault.On the basis of discussion on anomalous mechanism of H₂ on the hidden active fault,we suggest that H₂ is not generated in biological process butis a product of degassing in rupturing of the basement schist and gneiss or water-rock reaction.H₂ anomaly is closely related with fault movement whether H₂ is produced in rupture of rock or in water-rock reaction.

Key words: North China, Hidden active fault, H₂ anomaly, Gas geochemical method

摘要： 在华北北部3条断裂活动性和地震活动性差异较大的隐伏断裂上取54个土壤气样品。经对比研究发现,隐伏活动的唐山断裂和夏垫断裂上,H₂异常显着,一般比背景值高几十倍；而隐伏不活动的香河-皇庄断裂上,H₂则没有异常。在探讨隐伏活动断裂H₂异常机制中,认为H₂不是生物作用的产物,而是来源于结晶基底片岩、片麻岩等的破裂或水岩反应。不论H₂来源如何,它都与断裂活动密切相关。

关键词: 华北, 隐伏活动断裂, H₂异常, 气体地球化学方法