海南岛沉积建造特征及大地构造问题

海南岛是欧亚大陆壳的南缘。作者主要依据沉积建造特征及其演化、空间分布和大地构造属性,并结合岩浆活动等重要标志,认为海南岛经历了地槽、地台、地洼三个大地构造发展阶段。以岛南九所—陵水深断裂为界,岛中岛北现阶段属东南地洼区,前寒武纪一早古生代为地槽区,晚古生代为地台区;深断裂以南为南海地洼区,前寒武纪时为地槽区,古生代演化为地台区。全岛早三叠世末同时进入地洼发展阶段。岛西石碌铁矿和近年发现的戈枕金矿成矿带皆位于前寒武纪地槽构造层内,皆受地洼构造叠加改造影响,皆属多因复成矿床。

CHARACTERISTICS OF SEDIMENTARY FORMATIONS AND SOME GEOTECTONIC PROBLEMS ON HAINAN ISLAND, CHINA

Hainan Island is located in the transition zone between the Eurasia continental crust and the Pacific oceanic crust. Based on the characteristics, temporal and spatial distribution, and geotectonic nature of sedimentary formations and magmatism, the author points out that the Hainan Island has experienced three stages: geosynclinal, platform and diwa. The island was divided into two parts by Jiusuo-Lingshui deep-seated fracture before the Early Triassic. The central and northern parts belong to the SE. China Diwa Region, and was a pre-Cambrian-Early Paleozoic geosyncline and a Late Paleozoic platform. The southern part belongs to the South China Sea Diwa Region, and was a pre-Cambrian geosyncline and a Paleozoic platform.The island entered the diwa stage as a whole at the end of the Early Triassic.The Shilu iron ore deposit, located in the western part of the island, and the Gezheng gold metallogenic zone occur within the pre-Cambrian geosynclinal strata, They have been influened and reworked by diwa structures, being polygenetic compound ore deposits.