| Jia Qi,Fan Dejiang,Sun Xiaoxia,Liu Ming,Zhang Wenqiang,Yang Zuosheng. 2019. Grain size characteristics of the carbonate-free fraction of surface sediments from the Southwest Indian Ridge area and its geological significance. Acta Oceanologica Sinica, 38(2):34－43 |
| Grain size characteristics of the carbonate-free fraction of surface sediments from the Southwest Indian Ridge area and its geological significance |
| 西南印度洋中脊表层沉积物非碳酸盐组分的粒度特征及其地质意义 |
| Received:January 05, 2018 |
| DOI：10.1007/s13131-018-1273-6 |
| Key words:Southwest Indian Ocean carbonate-free fraction grain size distribution pattern end member model provenance |
| 中文关键词: 西南印度洋 非碳酸盐组分 粒度分布 端元模型 物源 |
| 基金项目:China Ocean Mineral Resources Research and Development under contract No. DY125-11-R-04; the National Natural Science Foundation of China under contract No. 41676036. |
| Author Name | Affiliation | E-mail | | Jia Qi | Key Laboratory of Submarine Geosciences and Prospecting Techniques of Ministry of Education, Ocean University of China, Qingdao 266100, China | | | Fan Dejiang | Key Laboratory of Submarine Geosciences and Prospecting Techniques of Ministry of Education, Ocean University of China, Qingdao 266100, China
Laboratory for Marine Geology and Environment, Pilot National Laboratory for Marine Science and Technology(Qingdao), Qingdao 266061, China | djfan@ouc.edu.cn | | Sun Xiaoxia | Key Laboratory of Submarine Geosciences and Prospecting Techniques of Ministry of Education, Ocean University of China, Qingdao 266100, China | | | Liu Ming | Key Laboratory of Submarine Geosciences and Prospecting Techniques of Ministry of Education, Ocean University of China, Qingdao 266100, China | | | Zhang Wenqiang | Key Laboratory of Submarine Geosciences and Prospecting Techniques of Ministry of Education, Ocean University of China, Qingdao 266100, China | | | Yang Zuosheng | Key Laboratory of Submarine Geosciences and Prospecting Techniques of Ministry of Education, Ocean University of China, Qingdao 266100, China | |
|
| Hits: 1351 |
| Download times: 1062 |
| Abstract: |
| The carbonate-free fraction of 20 surface sediments collected from the ultraslow-spreading Southwest Indian Ridge (SWIR) was studied by grain size analysis and mineralogical analysis with X-ray powder diffraction (XRD), stereo microscopy and scanning electron microscopy (SEM). The characteristics of the carbonate-free fraction of the sediments were obtained, and related influential factors were discussed. The results show that the mean grain size of this fraction is in 1.96Φ-8.19Φ, with poorly sorting and unimodal, bimodal or irregular bimodal distribution patterns. Four grain size end members of the fraction are derived with the End Member Model method. The finest end member EM1 shows a significant contribution of terrigenous materials of the aeolian input and sediment carried by the bottom current. End member EM2 with medium size mainly reflects sediment of a siliceous bio-clast origin. EM3 and EM4 are interpreted as representing the coarser volcanic materials related to bedrock weathering or volcanic activities. Multi-provenance is the dominant factor controlling the grain size pattern of the carbonate-free fraction of the sediments in that area. In addition, sediment transport processes such as the bottom current and wind are the minor factors that influence the grain size distribution of the carbonate-free fraction sediments. |
| 中文摘要: |
| 本文对采自超慢速扩张脊-西南印度洋中脊处的20个表层沉积物样品中的非碳酸盐组分进行了粒度、X-ray粉晶衍射、体式镜下鉴定以及扫描电镜等综合分析，阐明了其粒级构成和影响因素。结果表明，非碳酸盐组分的平均粒径介于1.96-8.19 Φ，分选差，其频率曲线发育单峰、双峰及不规则双峰式。利用端元模型分解出四个粒级端元，端元1显示了由风和底层流搬运而来的物质对细粒非碳酸盐组分沉积物的重要贡献；端元2的主峰区间反映了硅质生源组分的存在；端元3和端元4可作为源自海底基岩风化或当地火山活动的粗粒火山物质的代表。多物源的存在是造成非碳酸盐组分粒度差异的主因，其次还受到底层流、风等搬运过程的控制作用。 |
|
HTML
View Full Text
View/Add Comment Download reader |
| Close |
|
|
|
