Preliminary analysis of the data indicates that the field intensity undulates in SW-NE direction nearly perpendicular to the regional tectonic trend. The amplitude of these variations range approximately from 30 to 90 γ over wavelengths varying nearly from 38 to 70 km. We have made a combined inversion of the data with the unpublished Bouguer gravity map of the country along a N-S profile in the central region and find that the data are reasonably well matched with predictions of a simple two-dimensional block model. The model consists of a layer overlying a half-space. The variables of the model are the thickness and density of the surface layer and the susceptibility of the basement rock. The observed variation of the magnetic field and Bouguer anomalies for the selected profile may be accounted for either by the simultaneous northward density reduction of about 0.06 g/cm3 in the surface layer and approximately 15% increase of the basement susceptibility, or else by nearly 800 m variation of the sedimentary thickness. 相似文献
This paper presents and analyzes paleo-liquefaction features found in the State of Kuwait. The features are cemented sand and gravel-filled dikes of Pleisto–Holocene age with appearance and composition similar to typical “sandstone pipes.” The significant age difference between the cemented dikes and the surrounding loose sand, the size and spatial distribution of the dikes, and the local geologic and hydrologic setting all suggest that the feature probably results from a single large event of seismic origin. Likely hypotheses include shaking during large earthquakes or seiching of tsunami-like waves. Additional research is needed to identify the exact cause of these dike formations, which is important for the purpose of improving seismic risk and vulnerability assessment of the Arabian Gulf countries. The search may also help explain the disappearance of an ancient civilization that lived in the same region approximately seven thousand years ago.
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