多金属结核加密小区深拖资料与地质取样覆盖率、丰度的对比

Contrast study to data from geological sampling and deep-tow system of dense portion in China Pioneer Area

采用深拖系统计算软件包法,对多金属结核加密小区内深拖系统资料与地质取样覆盖率、丰度进行了对比和分析,结果表明:(1)加密小区多金属结核的分布具有不连续性,在深拖系统与地质取样的站位资料相对误差不大的情况下,两者平均值的相对误差却比较大,因此,在圈定矿区内矿体的分布时,仅依靠加密地质取样数据是不够的,还需要利用光学、声学等多种手段进行连续调查,获取更多的资料来评价矿区。(2)深拖资料较地质取样获取的丰度数据值小,绝对误差最大值可达4.907 kg/m2,相对误差最大值为27.9%,这主要是由于丰度是通过覆盖率、粒径的回归公式计算所得,由于加密小区局部多金属结核为半埋藏和埋藏型,使深拖系统在进行图像采集时无法探测到这部分的结核,造成了计算值偏小的现象。因此,在对丰度进行计算时,需要根据多金属结核的埋藏程度、产状等不同因素对计算公式或计算结果进行适当修正。

The abundance is main parameter to enclose the mine body and resource evaluation for polymetallic nodules,contrast study to data from geological sampling and deep-tow system of dense portion in China Pioneer Area was analyzed in this paper.The continuous length is 302 meters and the total length is more than 14 kilometers for east dense portion,the continuous length is 1063 meters and the total length is more than 28 kilometers for west dense portion.Accumulation curve for coverage of west dense portion was broken-line shape,the distribution of polymetallic nodules is in-continuous.Enclose the mine body distribution is unreliable just depend on dense geological sampling,therefore continuous data acquired by optical survey or acoustical survey is needed.The abundance analyzed from deep-tow photo-picture is the computational result by empirical formula base on correlation for abundance to coverage and granularity.The coverage has errors unavoidably,and empirical formula is not exact,therefore to get more exact abundance,we have to improve empirical formula.In east dense portion,mostly polymetallic nodules lie on seabed surface layer,and its granularity are larger,abundance of calculating is close to the actual value.In west dense portion,polymetallic nodules granularity is smaller and partial embedded in seabed,coverage analyzed from deep-tow photo-picture are lower than the actual values,The correlation analysis indicated that abundance has a positive correlation with coverage,consequently,the abundance calculated from coverage and empirical formula which is provided through geological sampling are lower than the actual values.We suggest that the empirical formula need to add a new parameter,that is the degree of the polymetallic nodules embedded in seabed,which is associate with the distribution range.