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观察西南印度洋脊(SWIR)27洋段(据Cannat等(1999)洋脊分段及命名)高分辨率多波束资料,发现其50.5°E轴部为一火山喷发高地,总体地形特征似乎类似受热点影响的洋脊。对该段洋脊地形作了详细分析,并结合受热点影响洋脊具有的一般特征,从地形地貌、地球物理场、岩石地球化学等方面分析了该段洋脊受热点影响的可能性。地形上缺少轴外地形表达,两翼也没有不对称现象;岩石地球化学上最普遍分布的仍是正常MORB。再者,在Crozet热点的相对运动历史轨迹上没有留下明显的痕迹,因此,其对相关洋脊产生有效影响的可能性并不大。综合SWIR 27洋段各方面特征,可说明其确实受某种因素影响,导致岩浆通量相比邻近洋段有大幅增加,但这种因素可能不是受热点影响,而是与大西洋中脊(MAR)上三段轴部地形异常的洋脊一样,是产生于由不均一地幔导致的洋脊局部岩浆增加。
Observing the high-resolution multi-beam data of the 27th member of the Southwest Indian Ridge (SWIR) (according to Cannat et al. (1999)), it is found that the 50.5 ° E axis is a volcanic eruption and the overall topographical features appear to be similar The hot ridge of influence. In this paper, the ocean ridge topography is analyzed in detail, and the general characteristics of ocean ridge influenced by the hot spots are analyzed. The possibility of hotspot influence on the ocean ridge is analyzed from topography, geophysical field and lithochemistry. There is a lack of off-axis topography on the terrain, and there is no asymmetry between the two wings; the most commonly distributed normal geochemical lithology is still normal MORB. Moreover, there is no obvious trace on the historical trajectory of relative motion of the Crozet hotspot, so it is unlikely that it will have an effective impact on the related ridge. Combining the characteristics of SWIR 27 with other aspects indicates that it is indeed affected by a certain factor, resulting in a substantial increase in magma flux over the adjacent oceanic segment. However, this factor may not be affected by the hotspot but with the mid-Atlantic ridge (MAR ) The upper ridges of the upper three-section shales are similar to those of the ridges of the ocean ridge resulting from the heterogeneity of the mantle.