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本文依据温泉、地震、构造、岩浆岩分布及其热破裂实验结果,论述了闽粤地区热场特点,讨论断块活动与热震关系。研究表明,燕山运动以来,断块分异作用强烈,与地壳深部二次重要热幕活动(距今90—120百万年及157—165百万年)密切相关。现代热场主要是中生代热幕活动继续发展的结果。分析发现,闽粤构造活动在新生代,其岩浆活动的前峰明显减退。但却存在自北东往西南冷热交替的块断热震耗散结构特征。断块活动性越强,热震效应越显著,同时呈现从内陆向台湾渐次增强特点。剖折闽南—粤北断块的热震能量耗散比率,表明每一断块具有特定的耗散结构。这是地壳下部与上地幔进行能量传递、转换过程的渠道。它主要取决于上地幔热流及向横不均匀性。热震能流约占地表大地热流2%±。本文根据等效原理,探讨构造力和热应力对板内地震孕育及破裂机制联合作用问题。提出“菱形”断块的周边的深断层端点、拐点是易于热破裂有利场所,并可能存在曼森—科芬效应导致深部岩石热疲劳和弹性破裂——发生地震。说明研究热震效应是具有理论和实用价值的新课题。
Based on the results of hot springs, earthquakes, tectonics, magmatic rocks and thermal rupture, the paper discusses the characteristics of the thermal field in the Min-Yue area and discusses the relationship between the faulting activity and thermal shock. The study shows that since the Yanshan movement, the fault block has a strong differentiation effect and is closely related to the second major hot-curtain activity in the deep crust (90-120 million years ago and 157-165 million years ago). The modern thermal field is mainly the result of the continued development of the Meso-Mesa hot-curtain activities. The analysis shows that in the Cenozoic, the tectonic activity of Min-Yue region decreased obviously. However, there is a block thermal shock dissipative structural feature alternating from cold to heat in the southwest to the northwest. The more active the fault block, the more obvious the thermal shock effect, meanwhile, the characteristic gradually increases from inland to Taiwan. The thermal shock energy dissipation ratio of Minnan-Yuebei fault block in the fault zone shows that each fault block has a specific dissipation structure. This is the channel between the lower crust and the upper mantle for energy transfer and conversion. It depends mainly on the upper mantle heat flow and lateral heterogeneity. Thermal shock energy flow accounts for about 2% of ground surface heat flux. Based on the principle of equivalence, this paper discusses the combined effect of tectonic force and thermal stress on in-board earthquake breeding and rupture mechanism. The endpoints of the deep faults around the “diamond” fault block are proposed. The inflection point is a favorable site for thermal cracking, and the Manson-Coffin effect may lead to thermal fatigue and elastic fracture of the deep rock. It is a new topic that has theoretical and practical value to study the thermal shock effect.