The Anylasis Of The Environmental Charcters Of Modern Marine Hydrothermal Activity Regions

Study of modern marine hydrothermal activity and mining process has become hot spot of international science nowadays . In order to study the modern marine hydrothermal activity system furtherly (including hydrothermal cycle and causal matter transportation, the rock and water interaction and causal elements transfer and transform, mining mechanism and causal mineral resources, hydrothermal diffusing and the causal influence, hydrothermal creatures and the influence to such questions as the life origin), we must know firstly the geological environment conditions that hydrothermal activities distribute, because the geological environmental conditions of hydrothermal activity areas control the distribution and dimensions of areas. the occurrence of hydrotherm and its transportation ways -, the mechanism of the sedimentation and mining processes. the size and attitude of ore bodies and all the geological processes after the mining.The thesis is one important part of the third item named "the exchange between seawater and marine material and energy" of the national emphasized study and developing plan items (973) named "the deep sea process and record of interaction among layers of the earth" , it is also an important part of the national nature and science funds items(40246024)0 On the basis of collecting the field-measured bathometric data and analysis data of sediments from Okinawa hydrothermal activity fields, extensive bathometri. seabeanu seismic profiles. geophysicaK geochemicaK tectonic and sedimentary data of other main typical hydrothermal activity fields are collected, all the collected data are picked up% rearranged and some figures are drawn.On the basis of systematically analytical work, the progresses of the hydrothermal activity investigation and study in and out of country are introduced, and the characters of spacial distribution bathometric distribution. topographical and geomorphic environment. tectonic environment .sedimentary environment and basic geophysical environment of the hydrothermal regions are contrasted . analyzed and concluded, the most favorable geological settings of hydrothermal activity distribution are discussed .Study shows that though modern marine hydrothermal activities distribute widely in the different tensile tectonic environments such as the mid-ocean ridges N the convert faults. back-arc spreading basins and modern marine volcanic areas, they actually occur in the special topographical and tectonic environmental conditions . The tectonic conditions have important controlling effects to hydrothermal activities and sedimentation, hydrothermal cycle channels (tectonic fissures ) are precondition that hydrothermal activities occur in, and at thesame time, they can also decide the form of mining ways of hydrothermal ore deposits?The geological conditions of hydrothermal activities are controlled by the regional tectonic environments and local tectonic factors ?Different regional tectonic environment corresponds the different location of the hydrothermal activity ?The local tectonic factors such as depth, volcanic activity, the developing stages of tectonic fissures, topomorphical shape, geological traps, can also affect the ejective ways of hydrothermal fluids, the stability of hydrothermal sytem, shape, attitude, size, purity of hydrothermal activity bodies ?The magmatism is the important embodiment and product of tectonic activities, and the driving power (heat) sources of the hydrothermal activities.Topographical conditions directly affect the size and dimension of hydrothermal deposits as the outside token of the tectonic conditions e The topographical high is the main places to develop hydrothermal activity, mid-ocean ridges rifts zones, trapped basins in the back-arc spreading basins, graben walls related to the faulting process, rift valley faults, calderas on the seamount, fissures system in axial grabens are all the tectonic parts hydrothermal activities often occuro Besides those, triple-junction zones, places that transform faults connect with ridges, trans...