Impact and implications of the Afro-Eurasian collision south of Cyprus from reflection seismic data
Impact and implications of the Afro-Eurasian collision south of Cyprus from reflection seismic data
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DOI：
10.1016/j.tecto.2014.04.002
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发表时间：
2014-06
期刊：
影响因子：
2.9
通讯作者：
Jennifer Klimke;A. Ehrhardt
中科院分区：
文献类型：
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作者：
Jennifer Klimke;A. Ehrhardt
东地中海的塞浦路斯弧代表了非洲板块和欧亚(安纳托利亚)板块之间的活动碰撞前沿。沿着塞浦路斯弧线，埃拉托塞尼海山被认为自上新世晚期至更新世早期以来一直阻碍着非洲板块的北上运动。基于塞浦路斯近海埃拉托塞尼海山和莱凡特盆地西部的密集二维反射地震剖面，对埃拉托塞尼海山-莱万特盆地-赫卡特斯隆起三个过渡带的塞浦路斯弧形碰撞前缘进行了新的观测。数据表明，莱万特盆地充填了约1000万千米的中生代早期(可能是侏罗纪)至上第四纪的沉积，仅有局部变形影响到中新世-渐新世岩石单元。沉积物直接向西的埃拉托塞尼海山陡峭的东侧和向北的Hecataeus的南侧隆起。这些沉积物没有显示出可能与碰撞有关的变形，甚至在两个突出的构造附近也没有变形。黎凡特盆地中新世底部反射层由于中中新世反射层的重叠而尖灭，表明埃拉托塞尼海山和赫卡特斯海隆的抬升。与埃拉托塞尼海山以北的梅西期蒸发岩不同，列凡特盆地的盐类，甚至靠近赫卡特斯海隆的盐类，在构造上是不变形的。这意味着碰撞前锋位于该单元的北部，赫卡特斯隆起保护其以南的沉积物免受与非洲板块和安纳托利亚板块碰撞有关的变形。
The Cyprus Arc in the Eastern Mediterranean represents the active collision front between the African and Eurasian (Anatolian) Plates. Along the Cyprus Arc, the Eratosthenes Seamount is believed to have been blocking the northward motion of the African Plate since the Late Pliocene–Early Pleistocene. Based on a dense grid of 2D reflection seismic profiles covering the Eratosthenes Seamount and western Levant Basin offshore Cyprus, new observations regarding the Cyprus Arc collision front at the triple transition zone Eratosthenes Seamount–Levant Basin–Hecataeus Rise are presented.The data show that the Levant Basin is filled with ~ 10 km of sediments of Early Mesozoic (probably Jurassic) to Plio-Quaternary age with only a localized deformation affecting the Miocene–Oligocene rock units. The sediments onlap directly against the steep eastern flank of the Eratosthenes Seamount to the west and the southern flank of the Hecataeus Rise to the north. The sediments show no deformation that could be associated with collision and are undeformed even very close to the two prominent structures. Pinching out of the Base Miocene reflector in the Levant Basin due to onlapping of the Middle Miocene reflector indicates uplift of the Eratosthenes Seamount and the Hecataeus Rise. In contrast to the Messinian Evaporites north of the Eratosthenes Seamount, the salt in the Levant Basin, even close to the Hecataeus Rise, is tectonically undeformed.It is proposed that the Eratosthenes Seamount, the western Levant Basin and the Hecataeus Rise act as one tectonic unit. This implies that the collision front is located north of this unit and that the Hecataeus Rise shields the sediments south of it from deformation associated with collision of the African and Anatolian Plates.