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古奥斯陆裂谷/奥斯陆地堑体系在地球物理上的特点是有一个明显的重力高。用一种挠曲的反演方法对这个地区的重力资料进行重新解释,结果表明:成其为主要原因的物体有0.06g/cm~3的密度差。反演结果也指出这类物体多半位于下地壳的上部并且向东延伸,远远超出地堑本区之外。对断裂前后地壳厚度的估计表明,裂缝开始在南面,然后改为向北。相应的旋转极位于奥斯陆城北北东大约240 km。7个局部小地震震源位于异常体的周围,这正如重力模拟推导出的,包括用NORSAR资料做的三维成象的地震调查还没能提供足够的证据,来说明岩石圈中的软流层物质的侵入是奥斯陆地堑运动的一部分。这里作出的解释是在大约150—200 Ma期间内,奥斯陆裂谷的地球物理特征和奥斯陆地堑的发展过程在上地幔中被明显地减弱了。最后,假定软流层进入岩石圈后发生了一个相对小的莫霍交叉断面地区,相对坚硬的上地壳部分地阻止了基性岩岩浆的进一步升高,因此引起了奥斯陆地堑外向东扩展的10—20 km深度范围的横向流动。
The geophysical characteristics of the ancient Oslo rift / Oslo grab system have a markedly high level of gravity. A deflected inversion method is used to reinterpret the gravity data in this area. The results show that the density of 0.06 g / cm ~ 3 is the main reason for this. Inversion results also indicate that most of these objects are located in the upper part of the lower crust and extend eastward beyond the area of the graben. Estimates of the thickness of the crust before and after the break show that the crack started south and then changed north. The corresponding pole of rotation is about 240 km north-east of Oslo. Seven local minor earthquakes are located around the anomalous body, as deduced from gravity modeling. Seismic surveys, including three-dimensional imaging using NORSAR data, have not provided sufficient evidence to demonstrate that the asthenospheric material in the lithosphere The invasion is part of the Oslo grabore. The explanation here is that during the period of about 150-200 Ma, the geophysical characteristics of the Oslo rift and the development of the Oslo grabens have been significantly reduced in the upper mantle. Finally, assuming that the relatively shallow Moho cross-section occurs after the asthenosphere enters the asthenosphere, the relatively hard upper crust partially prevents the further increase of mafic magmatism, thus resulting in the outward expansion of the Oscillatus graben Lateral flow in the 10-20 km depth range.