ENDOGENIC IMPACTOGENESIS AND THE NATURE OF TEKTITES AND IMPACTITES

Diamond-generating explosive ring structures are caused by the rise of high-pressure fluids from the molten core of the Earth. This determin es the high energy level of their formation process (endogenic impacto genesis) and is the principal difference between this process and expl osive volcanism, the sources of which are intermediate-depth magma cha mbers. Such ring structures are not related to meteorite falls. Endoge nic impactogenesis is comparable in nature to explosive sources of ear thquakes. Its mains products are impactites, whose principle feature i s the development of diaplectic glasses (pseudomorphs after minerals). This implies an isochoric melting in the rigid basement of platforms as the temperature rises high enough to melt individual minerals. The process is accompanied by the separation of melts (with subsequent for mation of tektites, tagamites, etc.) and by a rise in pressure (the au toclave effect) and the crystallization of high-density minerals (coes ite, stishovite, diamond, lonsdaleite, and chaoite).