Reinterpretation of morphology and crustal structure in the Central Arctic Ocean Basin
Reinterpretation of morphology and crustal structure in the Central Arctic Ocean Basin
复制标题
北冰洋中部盆地形态和地壳结构的重新解释
DOI：
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发表时间：
1985
期刊：
影响因子：
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通讯作者：
J. Sweeney
中科院分区：
文献类型：
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作者：
J. Weber;J. Sweeney
冰站测深剖面和潜艇回声图显示，一个陡峭的悬崖至少有200公里长，高达1700米的救济亚平行于罗蒙诺索夫海岭。这个特征，以前被称为马文支线，在这里被解释为阿尔法山脊面向马卡罗夫的侧翼。西经160°以东，马卡洛夫盆地是一个狭窄的地堑状海槽，宽25至60公里，充满水平分层沉积物，这些沉积物大部分是在沿着盆地轴线建造马文海山之后沉积的。基底起伏与槽内地磁场变化以及罗蒙诺索夫海岭正断层的证据的关联表明，马卡罗夫海盆的这一部分是由典型的海底扩张过程以外的伸展特征产生的。重力模型表明，阿尔法海岭马卡罗夫侧翼以下的地壳厚度在16至20公里之间，大大低于根据地震折射工作已知的罗蒙诺索夫海岭以下26公里的厚度。有人认为，根据重力数据，邻近罗蒙诺索夫海岭的弗拉姆盆地地壳，可能是真正的海洋，比马卡罗夫盆地薄3-4公里。
Ice station bathymetric profiles and submarine echograms reveal a steep escarpment at least 200 km long with up to 1700 m of relief subparallel to the Lomonosov Ridge. This feature, formerly called the Marvin Spur, is here interpreted as the Makarov-facing flank of the Alpha Ridge. East of the 160°W meridian the intervening Makarov Basin is a narrow grabenlike trough between 25 and 60 km wide filled with horizontally stratified sediments that were deposited largely after the Marvin Seamounts were constructed along the basin axis. The association of basement relief with geomagnetic field variations within the trough plus evidence of normal faulting on the Lomonosov Ridge suggest that this segment of the Makarov Basin is an extensional feature produced by other than typical seafloor-spreading processes. Gravity models indicate that the crust below the Makarov flank of the Alpha Ridge ranges in thickness between 16 and 20 km, considerably less than the 26 km known from seismic refraction work to exist below the Lomonosov Ridge. It is argued, on the basis of gravity data, that adjacent to the Lomonosov Ridge the Fram Basin crust, which is probably truly oceanic, is 3–4 km thinner than that of the Makarov Basin.