【摘要】 <正> 本文主要是讨论中国东部中、新生代陆内裂陷作用及其伸展构造。前者指既裂又陷造成沟、槽的构造作用,是与造山作用相对应的。它所造成的伸展构造也是最长见的构造类型,发育于岩石圈演化的各阶段和各种不同的构造环境中。鉴于中国东部的油、气田和煤田及绝大多数强震都贮存或发生于中、新生代裂陷作用所造成的盆地中,因此对它们的研究无疑有重要的理论和实际意义。更多还原

【Abstract】 Meso-Cenozoic extensional tectonics can be related to coal, oil and gas resourees and to earthquakes. It has been the subject of many studies. The purpose of this paper is tosummarize briefly our present state of knowledge concerning the nature and origin of theMeso-Cenozoic intraplate extensions in eastern China. Four main problems are consideredhere, namely: 1. Pre-Mesozoic tectonic setting; 2. Meso-Cenozoic taphrogeny and the distri-bution of extensional structures; 3. The structural types and mechanical characteristics ofthe Meso-Cenozoic extension; and 4. Mechanism of the Meso-Cenozoic extension in easternChina. Mesozoic was a time of profound tectonic change in eastern China, when the entire re-gion was in a continental facies and developed into a succession of alternating NNE-trendingculminations and depressions. The first taphrogenic cycle began in late Jurassic to earlyCretaceous and the extension occurred within and behind the andesite volcanic arc alongthe continental margin. Another impoant taphrogenic cycle occurred during the Cenozoic,which contains two principal taphrogenic stages. Intraplate extensional structures have been viewed from the standpoint of high-anglenormal faulting. Other extensional features, such as low-angle normal fault, spoon-shapedfault, decollement, dyke swarms and zones of penetrative ductile flow have also receivedan attention. Strike-slip or transform fault zones may originate along the boundaries be-tween areas of differential extension. Extensional tectonics coincides the thinner, warmer and highly fractured areas, thusa mechanism consistent with the geology and geophysics of the eastern China requires def-inition of the vertical dimension. It is thought that the essential factors that governed the-ir formation are the mutual mechanical interaction of preexisting tectonic patterns, the in-itiation of thermal pulse in the asthenosphere, which convect mass and heat upward, and thestress field of the combined action of both the Pacific and the Indian plates.更多还原