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1995年,在“院士”号科学考察船的第35次航行中,用“M”号潜水器完成了与蛇纹石化超基性岩有关的现代热液田的地质-地球化学研究。该热液区位于北纬15°20′转换断层以南35海里,大西洋中脊裂谷的边缘台阶上。热液形成物有含金属沉积物、铁-锰矿物和铜、铁、锌的硫化矿石。业已查明,硫化物矿石是从成矿过程中盐度变化很大的热水溶液中沉积出来的。含金属沉积物的特点在于其富含 Fe、Mn、S、P、C_(有机)、Ba、Cu、Zn、Pb、Co、V以及 SiO_2。指出了这个地区的热液活动始于大约2.5～3万年前。硫化物矿石以具同心环带状构造为特征。它们由黄铜矿、闪锌矿、黄铁矿、白铁矿、斑铜矿、等轴方黄铜矿组成。硫化物硫同位素组成为+0.7‰～+13.8‰。所述热液形成物比其它洋中脊硫化物机构富含 Co 和重硫同位素。与早先知道的现代系统不同,流体的温度比较高,并以压力和盐度较高为特征。其成分中有超基性岩所特有的组份。流体在地表面以下的分离作用是流体演化与成矿沉积的重要机理。这种作用导致流体中硫同位素组成及流体的盐度发生变化。
In 1995, during the 35th voyage of the Scientific Expedition of the “Academy of Sciences”, the geologic-geochemical study of the modern hydrothermal fields related to the serpentinization of ultramafic rocks was completed with the “M” submarine. The hydrothermal zone is located 35 nautical miles south of the 15 ° 20’25 North Transfiguration fault on the margin of the Mid-Atlantic Ridge Rift. Hydrothermal formations are sulfide ores containing metal deposits, iron-manganese minerals, and copper, iron, and zinc. It has been determined that sulphide ores are deposited from hot aqueous solutions that vary greatly in salinities during mineralization. Metal-bearing deposits are characterized by their abundance of Fe, Mn, S, P, C_ (organic), Ba, Cu, Zn, Pb, Co, V and SiO_2. It is pointed out that hydrothermal activity in this area began about 2.5 to 30,000 years ago. Sulphide ores are characterized by a concentric annular banding. They consist of chalcopyrite, sphalerite, pyrite, white iron ore, bornite, equiaxed chalcopyrite. Sulfur sulfide isotope composition of +0.7 ‰ ~ +13.8 ‰. The hydrothermal formation is enriched in Co and heavy sulfur isotopes than other mid-ocean ridge sulfide mechanisms. Unlike previously known modern systems, fluids are warmer and feature high pressures and salinities. The composition of the ultrabasic rock-specific components. Fluid separation below the ground surface is an important mechanism of fluid evolution and mineralization. This effect causes changes in the composition of the sulfur isotopes in the fluid and the salinity of the fluid.