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横向洋脊通常被定义为位于50km断裂带内的与其平行的异常浅的地形高地,长度为50-1000km(图1)。它们的宽度一般小于50km,在横断面上表现为不对称地貌,这表明是挠曲成因的(图2)。已经提出一些概念性模式来说明横向脊的一般特征。然而,没有一个统一的模式能够解释代表这一组合的构造背景的广阔分布。 位于21°和24°N之间缓慢扩张的中大西洋脊水深图表明,沿凯恩断裂带东部延伸部分的在21°30′N处的另一个断续的脊轴存在两个横向脊(图1)。水深和地球物理资料分析结果表明,正断层作用出现于此两条断裂带东部翼部。关于岩石圈对正断层作用的挠曲响应的数值模拟是与沿横向脊所观察到的地貌相一致的。本文提出了正断层作用和横向脊的形成开始于～8Ma,中止于～3 Ma的方案。
Transverse ridges are usually defined as anomalously shallow topographic terrain within a 50-km fault zone parallel to it, with a length of 50-1000 km (Figure 1). Their widths are generally less than 50 km, exhibiting an asymmetric topography in the cross-section, indicating a cause of flexure (Figure 2). Some conceptual models have been proposed to illustrate the general characteristics of lateral ridges. However, there is no single model that explains the vast distribution of tectonic settings that represent this combination. The deep mid-Atlantic ridge water dip slowly expanding between 21 ° and 24 ° N shows that there are two lateral ridges along another discontinuous ridge at 21 ° 30’N along the eastern extension of the Kain fault 1). Analysis of water depth and geophysical data shows that normal faulting occurs in the eastern wing of the two faults. The numerical simulation of the flexural response to normalizing faults in the lithosphere is consistent with the observed topography along the lateral ridges. This paper presents a scheme of normal faulting and formation of lateral ridges beginning at ~ 8 Ma and ending at ~ 3 Ma.