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从东太平洋两座海山山顶采集了 Fe 氧化物软泥、绿脱石矿床和 Fe—Mn 结壳的样品。在低温(0—15℃)热液正在喷涌的地方,矿床由 X—射线非晶质 Fe 氢氧化物组成,富含 Fe(43wt%),而 Si 和 P(分别为4%和3.5%)含量较少,Mn(<0.01%)和其它痕量元素非常低。在没有观察到热液流动的地方,其它矿床由含非晶质物质和结晶不良的赤铁矿、针铁矿和蒙脱石的软泥及结壳组成。这些矿床含有稍多的 Mn(达2%)和其它痕量元素。活动的与不活动的矿床和结壳之间在矿物学和化学上的差异据解释起因于再结晶作用和与碎屑的、生物成因的、含氢的以及可能的热液硫化物物质的混合作用。从一海山中获取了 Fe—Mn 氧化物复盖的绿脱石矿床的样品。这些矿床含有与其它海底绿脱石矿床相似的成分,是在低温热液与海水混合期间在低温(30℃)下形成的。氧化物矿床几乎全部由长而细的纤维组成,在形态上与 Fe 氧化细菌种属酷似。这种细菌在催化海山热液的铁元素的氧化和沉淀方面可能起到重要作用。在两座相距很远的海山上产出的近乎一致的富纤维状氧化物表明,这种矿床类型在许多海山上可能是常见的,而过去未曾辨别罢了。
Fe oxide mucilages, nontronite deposits and Fe-Mn crusts were collected from two seamounts in the eastern Pacific Ocean. Where cryogenic (0-15 ° C) hydrothermal fluids are spewing out, the deposit consists of X-ray amorphous Fe hydroxide and is rich in Fe (43 wt%) and Si and P (4% and 3.5%, respectively) Less content, Mn (<0.01%) and other trace elements are very low. Where no hydrothermal flow was observed, the other deposits consisted of slime and crust containing hematite and goethite and montmorillonite containing amorphous material and poorly crystallized hematite. These deposits contain slightly more Mn (up to 2%) and other trace elements. The mineralogical and chemical differences between active and inactive deposits and crusts are explained by the fact that recrystallization and mixing with detrital, biogenic, hydrogenous and possibly hydrothermal sulphide substances is explained effect. Samples of a Fe-Mn oxide covered gabbro deposit were obtained from a seamount. These deposits contain similar composition to other marine chlorite deposits and are formed at low temperatures (30 ° C) during the mixing of low temperature hydrothermal fluids with seawater. Almost all of the oxide deposits consist of long, thin fibers that are morphologically similar to the species of Fe-oxidizing bacteria. This bacterium may play an important role in catalyzing the oxidation and precipitation of iron in seamounts. The near-consistent pleated oxide-like oxide produced on two seamounts offshore shows that this deposit type may be common on many seamounts, but has not been identified in the past.