Extensive salt deposition and remobilization influencing petroleum prospectivity of the Mandawa Basin: remote sensing manifestation confirmed by seismic results

This work reports remote sensing aided identification of salt deposition and remobilization within a sub-rounded structure with approximately equant dimensions in the Mandawa Basin. A calculated surface flow direction has revealed the sub-rounded structure from Shuttle Radar Topography Mission—Digital Elevation Model (SRTM DEM) data. Internally, the body contains several structural highs and lows reflected by multiple peaks and troughs displayed by profiles drawn across the body. Seismic interpretation results confirmed these structural highs and lows, and they conform to salt build-ups (salt pillows and domes) and sedimentary minibasins, respectively. Seismic work, a follow-up investigation of the remote sensing findings, involved qualitative interpretation of 24 seismic profiles, 7 of which were chosen to represent the findings. East Lika 1 well stratigraphy was used to assign the age of the studied interval, and confirm that features of interest are associated with salt deposition and remobilization. Moreover, the East Lika 1 well tie corroborated that the interpreted salt deposition and the associated build-ups are within the Nondwa Formation of the Pindiro Group. Remote sensing observation, coupled with seismic interpretation, has revealed that the Mandawa salt basin is more extensive than reported before. Oil seeps, which are potential indicators of a working petroleum system, have been reported in the Mandawa Basin. One of these seeps is adjacent to a mapped salt dome. This observation probably indicates the influence of salt tectonics in the Mandawa petroleum system. Further work on a better quality seismic dataset may help resolve the problem of hydrocarbon whereabouts as far as the influence of salt tectonics is considered.