Palaeocurrent dispersal patterns of Witwatersrand gold placers
Palaeocurrent dispersal patterns of Witwatersrand gold placers
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威特沃特斯兰德金砂矿的古水流扩散模式
DOI:
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发表时间:
1991
期刊:
影响因子:
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通讯作者:
J. Loen
中科院分区:
文献类型:
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作者:
W. Minter;J. Loen
Placer dispersal patterns in the Witwatersrand Basin have been established from available palaeodip indicators comprising isopachs of stratigraphic separations between markers and overlying unconformities against which they subcrop, isopleths of clast size, detrital heavy mineral grain size and mineral ratios, palaeochannel trends, and 5622 cross-bedding vectors. Unimodal trough cross-bedding data (with vector variances generally less than 3000), clast size, and assemblage information, have enabled us to define the distribution of placer deposits, which are considered to represent coalescing lobes on extensive braid deltas that spread out perpendicular to the margins of the depositories to cover areas of 100 km 2 and more