MS. Afraa Mohammed Eltahir Lecturer finished her master degree in GIS and remote sensing at Sudan Academy of Science.

Her master research is:

Groundwater Exploration Using Satellite Remote Sensing and GIS in North Darfur State,

Abstract:

Due to the aridity and ecological fragility of northern Darfur region severely restricts therearing of stock except camels and some desert sheep’s. The exploration of new locations ofpossible groundwater recharge and accumulation is required to augment the limited waterresources.
The objective of this study is the integration of data extracted from earth observation satellites and geological knowledge of the northern Darfur area using geographical information system in order to delineate prospective zone for groundwater resources.

This study indicate that in arid region of northern Darfur region water accumulates in thesubsurface of an ancient mega lake that is covered by windblown sand dunes and the regionturned to semi desert. The analysis of the lineaments interpreted from Landsat ETM+ dataindicate of the lake shore line which moves as the lake water decreased formed newboundary. Drainage system identified by digital elevation data indicates its control by normalfaults structures that have formed the graben basin of the lake. Remote sensing infrared,Radar imaging and DEM data, exploited in the study, help to confirm this result. The deepzone lying in water flow direction of continuous to sub continues aquifer, that have beenclassified as optimum groundwater recharge location, correspond well with those sites thatretain moisture longer as revealed by thermal TIR, and coincides with principle componentmoisture values lying in the lower topography as detected by radar image. The STRM datahad a profound effect in delineation of groundwater accumulation zone in the study area.Because the major rock in the study area is sandstone which has high porosity and the gentleto moderate slope of the surface, the deep central zone of the lake was the most potentialarea. The study also highlights the importance of the integration of different remote sensingtechniques to get the most conclusive information out of the available data.

The methodology developed in the research may be operationally applied in other similar environments in western and northern Sudan, as well as in other countries where the geological factors affecting groundwater storage and transmission are comparable.

Potential Recharge Zone of the study area

The high potential zone was delineated as the result of superimposing the digitalelevation model data and the hill shade effect to have a good understanding of the recharge area. The dark brown area in the Image is the potential recharge zone, and with some brighter areas which have high runoff Topographic profile of the potential recharge zone in the study area Topography of the potential recharge zone defined in the SRTM of the palaeolake. The x–z cross-section (bottom) shows the step-like shape of the topography at deep zonezone and with some brighter areas which have high runoff

Topographic profile of the potential recharge zone in the study area

Topography of the potential recharge zone defined in the SRTM of the palaeolake. The x–z cross-section (bottom) shows the step-like shape of the topography at deep zone