海洋地质与第四纪地质

本省沿海地区砂质海岸发育,蕴藏丰富的滨海砂矿.有工业价值的砂矿床10处,矿点20余个.根据矿床形成的地理位置和矿床类型可划分为3个成矿区.这些矿床均形成全新世中、晚期的沿岸沙堤、海滩、水下沙坝中,个别砂矿床赋存于中更新世北海组冲积层中.

Sandy coast, rich in placer deposits, well develops along tlie coastal area of Guangxi Autonomous Regiem. It has been found that there are 10 ore deposits and 20 localites with economical values. According to geographical positions and types of raineral deposit, there are 3 ore districts as follows: the Fang-cheng-Hepu ilmenite, zircon and rutile mineral area, the Fangcheng-Beihai glass silica sand area and the area of silica sand as building materials. The coastal placer deposits are mostly forraed in the coastal sand bar, beach, underwater bar of middle-late Holocene, and only a few show their presence in alluvium of middle Pleistocene. In the paper, not only characteristics of the placer deposits have been described but also enrichment conditions such as material source, climate, hydrodynmics, coastal types, geomorphic features, neotectonics and sldiment grain sizes have been discussed.