Electrical investigation for ground water bearing sediments in River Gash Basin–Kalahot (Kassala State)‎

مقدم أطروحة جامعية

Ali, Ishaq Babakir Usman Faki

مشرف أطروحة جامعية

Farwah, Abd Allah Jumah

الجامعة

جامعة أم درمان الإسلامية

الكلية

كرسي اليونسكو للمياه

دولة الجامعة

السودان

الدرجة العلمية

ماجستير

تاريخ الدرجة العلمية

2007

الملخص الإنجليزي

In exploration and evaluation of ground water, the hydrogeologist deals with the geophysical methods which provide evidence of the subsurface formations.

The theme of this study is the resistivity investigation for groundwater bearing sediments in River Gash Basin, Kalahot Scheme (Kassala State). Kassala town and the surrounding villages depend mainly on groundwater in its all activities.

The aim of the resistivity investigation carried out in the area of Kalahot Scheme is to delineate the geological structure of the area and to determine the thickness of the alluvial deposits.

About thirty vertical electrical sounding measurements were carried out using an ABEM-SAS 300C Terrameter, using Schlumberger arrangement on an area of almost 20000 feddans.

The area of study lies between longitudes 36º 30´–36º 15´ E and latitudes 15º 30´–15º 45´ N.

Kalahot area lies about 10km West of the alluvial deposit of the Gash River.

The River Gash Basin area is subjected to several studies showing two types of aquifers, the alluvial deposits around the Gash River as main aquifer and the fracture in the Basement Complex as secondary one.

The presence of the Basement makes the exploration for the groundwater difficult and complicated.

Therefore the study concentrated on alluvial deposits to assess the groundwater bearing sediments in Kalahot.

The main purposes of this study is presented in the interpretation of the resistivity data obtained by the Vertical Electrical Sounding (VES) to determine the saturated gravelly or sandy beds within the upper alluvial sediments.

Exploration for fractures within the weathered Basement rocks to select suitable well sites for drilling is also put as target. The main data used are the thematic maps of the study area, the previous studies and the Vertical Electrical Sounding (VES) data. Thirty VES points are arranged in six profiles.

The field curves are modeled with the aid of Resix, which is a computer program for the analysis and interpretation of VES data.

The result of interpretation is a group of curves and resistivity models.

From the interpretation and analysis of VES data the geoelectrical cross sections of the area were obtained.

They exhibit intercalation between the sand, clay, and clayey sand with shallow Basement Complex.

The aquifer in the study area is mainly formed from channel deposits which grade from fine sand to coarse sand and granules in some places.

These facies change laterally to slow permeable layers in some parts of the area.

The sand deposits which concentrates in the eastern side of the area with thickness ranging from 20 to 30m is considered as good aquifer.

Following the Gash deposits two aquifers are recognized as the upper one which is characterized with fine sediments of sand with thickness 2-12m, while the lower aquifer is formed of coarser sand deposits with thickness that reaches 20m.

Three points are recommended as suitable well sites for drilling.

التخصصات الرئيسية

علوم الأرض و المياه و البيئة

الموضوعات

• السودان
• كسلا(ولاية)
• الرواسب

عدد الصفحات

134

قائمة المحتويات

• APA
• MLA
• AMA

لغة النص

الإنجليزية

نوع البيانات

رسائل جامعية

رقم السجل

BIM-362642