钴结壳具有 Co、Ni、Cu 和 Mn 及其他金属的潜在矿产资源和储存在结壳层中古环境信息的双重意义。与深海多金属结核和热液硫化物矿床相比，具有较高 Co、Ni 和 Pt 含量的海山钴结壳有可能成为商业勘探的潜在目标。为合理地估算出全球三大洋海山钴结壳资源量，基于我国西太平洋海山钴结壳拖网采样调查资料和对太平洋海山钴结壳资源分布规律和钴结壳矿区圈定参数指标的深入研究，按海山不同高度、不同洋壳年龄赋予不同结壳厚度，进而计算出全球三大洋海山钴结壳分布面积为3039452．14 km2和干结壳资源量为（1081．1661～2162．3322）×108 t。太平洋海山钴结壳分布面积为2123087．12 km2和干结壳资源量为（513．244～1026．488）×108 t，大西洋海山钴结壳分布面积为512509．74 km2和干结壳资源量为（116．5032～233．0064）×108 t，印度洋海山钴结壳分布面积为403855．28 km2和干结壳资源量为（81．4849～162．9698）×108 t。三大洋海山钴结壳的 Mn、Co、Ni 和 Cu 金属量分别为（138．8480～277．6960）×108 t，（3．9676～7．9352）×108 t、（2．7936～5．5872）×108 t 和（0．8251～1．6502）×108 t。根据钴结壳的 Co 含量、Co 通量和厚度相关分析，所赋予的钴结壳厚度占理论推测厚度的6．10％～12．20％，这与 Ku 等得出“钴结壳生长时间约占其整个生命史4％”的认识非常相近。三大洋海山钴结壳实测厚度与赋值厚度对比分析表明，太平洋海山钴结壳赋值厚度平均值为1．87 cm，实测厚度平均值为1．77 cm，相对误差为5．35％，大西洋和印度洋相对误差分别为18．18％和23．23％。研究数据表明按海山高度和洋壳年龄所赋的钴结壳厚度基本合理，估算出的钴结壳资源量基本可靠。本文首次估算出三大洋海山钴结壳资源量，为整个海盆和三大洋海山钴结壳资源量估算提供了新方法。%Marine cobalt (Co)-rich ferromanganese crusts are important because they are potential mineral resources for Co,Ni,Cu,Mn and other metals,and the paleoenvironment signals have been stored in their stratigraphic lay-ers.Compared with pelagic polymetallic nodules and hydrothermal deposits,the Co-rich crust has higher Co,Ni and Pt contents,which make it possible for commercial exploitation.Based on Chinese surveyed data for Co-rich ferro-manganese crust on some seamounts in the western Pacific,we performed a series of detail studies on the distribu-tion of Co-rich ferromanganese crust and parameter indexes for delineation of Co-rich ferromanganese crust re-sources on seamounts.Then,each seamount is endowed with the crust thickness according to its height and age of underlying ocean crust,and thereby we calculated the amount of dry crust resources in the three oceans (1 081.166 1~2 162.332 2)×108 t and distributed areas of crusts on seamounts (3 039 452.14 km2 ).And,the area covered by Co-rich ferromanganese crusts on seamounts in the Pacific,Atlantic,and Indian Ocean is 2 123 087.12 km2 ,512 509.74 km2 and 403 855.28 km2 ,respectively,and the dry Co-rich ferromanganese crust resources in the Pacific,Atlantic,and Indian Ocean are (513.244~1 026.488)×108 t,(116.503 2~233.006 4)×108 t and (81.484 9~162.969 8)×108 t,respectively.The contents of manganese,cobalt,nickel,and copper in the Co-rich ferromanganese crusts on seamounts in three oceans are (138.848~277.696)×108 t,(3.967 6~7.935 2)×108 t, (2.793 6~5.587 2)×108 t and (0.825 1~1.650 2)×108 t,respectively.Based on analyzing the relationship a-mong Co-contents,Co-fluxes and Co-crust thickness,the endowed crust thickness accounts for 6.10%~12.20% of the theoretical deductive thickness,which supports Ku’s conclusion that the crusts were actually growing for 4% of their lifetime.The average of endowed thickness is 1.87 cm and the average of measured thickness is 1.77 cm of Co-rich ferromanganese crusts on seamounts in the Pacific,and the relative error between endowed thickness and measured thickness is 5.35%.Correspondingly,the relative error in Atlantic and Indian Ocean is 18.18% and 23.23%,respectively.It shows that the endowed value for crust thickness on seamounts in the Pacific is reasonable and the obtained resource amount may be reliable.Finally,this paper provides a new method for estimating the re-source amount of Co-rich ferromanganese crust on seamounts in global deep-sea basins.
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