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为了研究印度河深海冲积扇，地震测量穿入基底，利用测量结果能够绘制阿拉伯海东北部的基底构造图，并描述它的地球动力学演化。基底的主要大地构造是一条ＥＷ向地堑，并伴有一个突出的中心，ＥＷ向地垒——Ｐａｌｉ－ｔａｎａ地垒。这条裂谷被若干ＮＥ—ＳＷ向的断层斜向切割。大的ＥＷ向磁异常同大洋性阿拉伯海盆的磁异常层序不连续。但是，这些磁异常与地壳中的反磁化作用是有联系的，表明这条裂谷位于与德干圈闭（ＤｅｃｃａｎＴｒａｐｓ）有关的被线状火山岩体侵入的拉伸大陆壳之下，或者说位于老于像在东南方向的Ｌａｘｍｉ海盆的年代２８（６４Ｍａ）大洋壳之下。伴随这些构造，在Ｌａｘｍｉ海岭从印度大陆的分离过程中ＮＥ－ＳＷ向断层随着走向滑移模式可以起转变方向的作用。笔者提出裂谷作用和大洋扩张已经发生在与连接大洋性Ｌａｘｍｉ海盆、ＮａｒｍａｄａＳｏｎ线性构造和Ｇｏｐ裂谷的三联点周围。这个阶段早于阿拉伯海盆的大洋扩张作用。这一解释符合前面提到的在年代２８之前印度和塞舌尔的初始分离说。Ｌａｘｍｉ海岭可能是后来离去附着到印度大陆的塞舌尔微板块的一部分。
In order to study the alluvial fan in the Indian River, seismic measurements penetrate the basement and the results of the measurements can be used to map the basement structure of the northeastern Arabian Sea and describe its geodynamic evolution. The main geotectonic structure of the basement is an EW trending graben with a prominent center and EW trending to the basement of the Pali-tana basement. This rift is cut obliquely by several NE-SW faults. The large EW magnetic anomaly is discontinuous with the magnetic anomalous sequence in the continental Arabian basin. However, these magnetic anomalies are related to the demagnetization in the crust, indicating that this rift is located below the tensile continental crust invaded by linear volcanic rocks associated with the Deccan Traps, or at It is older than the 28 (64 Ma) oceanic crust in the southeastern Laxmi basin. Accompanying these structures, the NE-SW strike can act as a direction-slip model as the Laxmi Ridge separates from the Indian continent. The author proposes that rifting and oceanic expansion have occurred around the triple point with the linear Laxmi basin, the NarmadaSon linear structure and the Gop rift. This stage precedes the oceanic expansion of the Arabian basin. This explanation is in line with the aforementioned initial secession of India and Seychelles by the 28th. The Laxmi Ridge may be part of a Seychelles microchip that later departed to the Indian mainland.