莺歌海盆地东北部邻区7条主要入海河流重砂矿物特征及其地质意义
摘要: 海南岛西部（琼西）是莺歌海盆地东北部的主要物质来源之一。本文对琼西7条主要河流入海口的现代河砂进行了重矿物含量、重矿物组合以及相关特征指数等分析，发现其重矿物含量、磨圆度、组合以及相关重矿物指数从北到南明显不同，反映出碎屑物质搬运距离和源区岩性也明显不同。北部珠碧江重矿物以钛铁矿、电气石、锆石、绿帘石和透闪石为主，磨圆度较差，反映物源主要为近距离的酸性至基性—超基性岩浆岩和变质岩；昌化江重矿物以钛铁矿、磁铁矿、锆石和榍石为主，磨圆比较好，物源可能主要为远距离的酸性和基性岩浆岩；中部北黎河和通天河重矿物以钛铁矿、电气石、锆石、石榴石和透闪石为主，基本没有磨圆，物源主要来自近源区，为未经远距离搬运的变质岩、酸性岩浆岩和基性火山岩；感恩河重矿物以磨圆度差的锆石、钛铁矿、榍石、电气石和褐铁矿等稳定—极稳定重矿物为主，反映源区主要为近距离搬运的岩浆岩；南部望楼河和宁远河重矿物以钛铁矿、磁铁矿、褐铁矿和绿帘石等稳定—不稳定矿物为主，反映的母岩主要为酸性岩浆岩、变质岩和中—基性岩浆岩。这些主要河流入海口的重矿物特征存在明显差异，这与其发源地、流经区域以及流经区域所发育的岩石类型相一致。通过研究琼西地区从北到南不同流域的重矿物组合体系，有助于开展莺歌海盆地源汇对比分析，建立不同区域油气储层碎屑物质来源的识别标志，对该盆地天然气储层物源识别具有重要的地质意义。
Characteristics and Geological Implications of Heavy Minerals from Seven Rivers in Adjacent Areas of Northeastern Yinggehai Basin
Abstract: Hainan located in adjacent areas of northeastern Yinggehai Basin, it is one of important sources of sediment to basin filling. In this paper, we analyzed the content, assemblages and index of heavy minerals in sediments which come form the mouth of the seven rivers in western Hainan. The study revealed that heavy minerals content, roundness, assemblages and index are obviously different from the north to south, reflecting the transport distance and parent rocks also different. The northern Zhubijiang mainly for near distance source, including a provenance of acid rocks with some metamorphic and basic-ultrabasic rocks, the dominated heavy minerals are ilmenite, tourmaline, zircon, epidote and tremolite; The northern Changhuajiang river is mainly for the long distance transportation of acid to basic rocks, the dominated heavy minerals are ilmenite, magnetite and zircon; The central Beilihe and Tongtianhe rivers are mainly from near distance source, the acid, basic and metamorphic rocks without long distance transporting, and the dominated heavy minerals are ilmenite, tourmaline, zircon, garnet and tremolite; The central Ganenhe mainly for stable-very stable minerals, they are zircon, ilmenite, titanite, tourmaline and limonite; The southern Wanglouhe and Ningyuanhe are from near transporting parent rocks, including a provenance of acid, basic and metamorphic rocks, the heavy minerals mainly for ilmenite, magnetite, limonite and epidote. Different characteristics of heavy minerals in different rivers are closely related to its source, the areas of transport and the rock types. By studying the different assemblages system of heavy minerals in different rivers, it can help to carry out source-sink comparison and analysis of Yinggehai Basin, to establish the identification signs of different detrital source area of oil and gas reservoir, and has an important geological significance for provenance identification of natural gas in different reservoir.
莺歌海盆地东北部邻区7条主要入海河流重砂矿物特征及其地质意义[J]. 沉积学报, 2014, 32(2): 228-237.
| 引用本文: |
莺歌海盆地东北部邻区7条主要入海河流重砂矿物特征及其地质意义[J]. 沉积学报, 2014, 32(2): 228-237.
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Characteristics and Geological Implications of Heavy Minerals from Seven Rivers in Adjacent Areas of Northeastern Yinggehai Basin[J]. Acta Sedimentologica Sinica, 2014, 32(2): 228-237.
| Citation: |
Characteristics and Geological Implications of Heavy Minerals from Seven Rivers in Adjacent Areas of Northeastern Yinggehai Basin[J]. Acta Sedimentologica Sinica, 2014, 32(2): 228-237.
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