| 南海北部陆坡气泡羽状流的发现:多波束水体数据 |
| |
| 引用本文： | 刘斌,刘胜旋.南海北部陆坡气泡羽状流的发现:多波束水体数据[J].海洋学报,2017,39(9):83-89. |
| |
| 作者姓名： | 刘斌 刘胜旋 |
| |
| 作者单位： | 广州海洋地质调查局 国土资源部海底矿产资源重点实验室, 广东 广州 510075 |
| |
| 摘 要： | 利用2016年在南海西北部陆坡琼东南海域采集的多波束水体数据，发现了海底气体渗漏至海水中形成的羽状流。在多波束数据上， 羽状流成火焰状，直径大约为30~50 m，从1 380多米的海底延伸至大约650 m的深度，高度超过700 m。在经过羽状流的浅剖剖面上，存在显示浅层气存在的声学空白区域，并识别出断裂和裂隙区域，但在水体中并无明显的异常。这可能是由于浅剖数据的分辨率不够未能捕捉到水体异常，或者气体渗漏具有间歇性。该海域存在明显的似海底反射显示，气体渗漏可能与水合物系统之间存在复杂的相互作用。由于缺乏经过羽状流的多道地震数据，难以对羽状流的形成机制进行进一步的推测。南海北部陆坡羽状流的发现对于理解被动大陆边缘的甲烷渗漏机制、水合物的形成与分解具有重要的意义。
|
| 关 键 词： | 南海北部陆坡 琼东南盆地 气体渗漏 羽状流 水体图像 |
| 收稿时间： | 2016/12/8 0:00:00 |
| 修稿时间： | 2017/2/8 0:00:00 |
Gas bubble plumes observed at north slope of South China Sea from multi-beam water column data |
| |
| Liu Bin and Liu Shengxuan.Gas bubble plumes observed at north slope of South China Sea from multi-beam water column data[J].Acta Oceanologica Sinica (in Chinese),2017,39(9):83-89. |
| |
| Authors: | Liu Bin and Liu Shengxuan |
| |
| Institution: | Key Laboratory of Marine Mineral Resource, Ministry of Land and Resource, Guangzhou Marine Geological Survey, Guangzhou 510075, China |
| |
| Abstract: | Methane emission from seabed is a wide phenomenon around the world. Gas bubble plumes were observed in the Multi-Beam(MB) water column echo image with the newly (2016) acquired data in the north slope of South China Sea. Gas bubbles manifest themselves as flares on the MB image, and have the diameter of about 30 to 50 m. Plumes emanating from the~1 380 m depth seabed to the~650 m depth, resulting heights of >700 m. On the sub-bottom profile passing through the plume, we found the acoustic blanking zone which may indicate the gas migration pathway, but no clear anomalies were observed in the water column. This may be explained by the low resolution of the sub-bottom profiler image or the intermittence of the gas seepage. Lacking of multi-channel seismic and geochemistry data, we cannot further infer the formation mechanism of the gas plumes. The discovery of gas bubble plumes in the north slope of south china may improve our understanding of the methane seepage on the passive continental marginal, and the formation and dissociation of gas hydrates. |
| |
| Keywords: | north slope of South China Sea Qiongdongnan Basin gas flares plume water column image |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《海洋学报》浏览原始摘要信息 |
| 点击此处可从《海洋学报》下载免费的PDF全文 |
