Multi-scale Lineament and Geological Mapping Elucidates Subsurface and Regional Tectonic Influences in Kuwait

Abstract

This paper presents efforts to generate a completely new surface dataset in the form of lineament maps at different scales using remote sensing techniques, to elucidate major subsurface & regional tectonic influences in Kuwait. USGS Landsat-7 imagery TM bands 1 and 4 were enhanced using image processing software for the regional lineament mapping of over 12,000 sq.km. area in central Kuwait. In ground truth, these were found to be linear relief features in the form of subtle escarpments, ridges, and valleys, occasionally forming characteristic drainage patterns. A total of 119 regional lineaments, with an average length of 6500m were mapped, which showed NW-SE and NE-SW trends. ESRI's high resolution world images of 70 km² area adjoining Mutla Ridge on the Jal Az-Zor trend, parallel to the northern coastline, were interpreted for detailed geological and lineament mapping, using ArcGIS Explorer. The area showed excellent rock exposures of Late Oligocene to Pleistocene ages. The lineaments observed were mainly of two types. The coastal lineaments were several hundred meters long and up to 12 meters wide linear depressions of subtle relief that appeared darker due to higher moisture content. On the other hand, the Mutla Ridge lineaments were longer, linear ridges, escarpments and prominent linear valleys often having lighter tone due to recent alluvial and aeolian sands fills. A total of 204 lineaments, with an average length of 300m, were mapped. The coastal lineaments showed primarily NW-SE trend while the Mutla Ridge lineaments showed both NW-SE and NE-SW dominant trends. The lineament analysis was carried out using GEOrient, and all maps were integrated on ArcMap 10.1 using topographic and image web base maps. The subsurface seismic and well data from nearby oil fields, were integrated with the findings of Jal Az-Zor area to conclude that a Tertiary fault shaped the straight NE-SW trending coastline, while the adjoining Jal Az-Zor escarpment is a geomorphic feature formed by the erosional retreat. The present study successfully relates surface based multi-scale lineaments using direct remote sensing observations with key subsurface structural elements for the first time in Kuwait. It is concluded that the Cenozoic compressional forces and the present day maximum horizontal stresses related to the Zagros orogeny, within the context of geodynamic stresses of the plate tectonic setting, shaped the surface and near subsurface structural elements of Kuwait.

AAPG Datapages/Search and Discovery Article #90194 © 2014 International Conference & Exhibition, Istanbul, Turkey, September 14-17, 2014