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The present integrated study is held to carry out the control of depositional and diagenetic processes on the reservoir potential of the Lower Cretaceous sequence within Nizampur Basin (Kahi Village section) and Kalachitta Range (Tora Stana section). This study was carried out in order to analyse the effect of the depositional and diagenetic processes on the reservoir potential of the studied strata. The Lower Cretaceous sequence at the western part of the Kala Chitta Ranges is mainly composed of sandy limestone and sandstone facies. Petrographic details show that the sandstone is mineralogically mature in both sections while it is texturally immature to sub-mature at Tora Stana section and sub-mature to mature at Kahi Village section. The microscopic details indicate that the sandstone is at Tora Stana section is deposited in inner to middle shelf setting, while it indicates moderate to high energy condition of beach to inner shelf setting in Kahi Village section. The results of Image J software shows that the porosity of this clastic succession ranges from 2-5% at Kahi Village Section, while in the fractured and dolomitic samples the porosity exceeds up to 13.5%. At Tora Stana section the average porosity ranges from 4-7%. The anomalously high porosity values may be the artefacts during thin section preparation. [ABSTRACT FROM AUTHOR]

The present study was undertaken to find out different geotechnical properties of Chitral slates for heavy construction such as dam components like a weir, diversion and intake, sand trap, headrace tunnel, access tunnel and tailrace. The work has helped to analyze the behavior of these rocks during construction and under the imposed loading of any proposed structure. The highly deformed Jurassic Chitral slates are exposed along a large anticline in the Hindu Kush ranges situated in district Chitral, Northern Pakistan. A total of six bore holes were drilled, approximately at a distance of 1 km for each sample, for a detailed study of core samples and internal condition of boreholes. These include water pressure test, water table, Standard Penetration Test (SPT)/Cone Penetration Test (CPT), joints and fractures, and lithology. The studied core samples are highly jointed; average five joints per meter are present, which are in filled by clay and iron oxide. As a result of these joints, the water loss is very high. Water pressure tests were carried out at a specific depth in boreholes in uncased section. The picker test results were 26.75, 22.95 and 15.90 in Geo-11A and Geo-15 respectively. Many of the tests were not successful because of the jointed strata where the water pressure did not exceed the required pressure. The SPT failed in overburden due to the presence of heavy particles like boulder etc. The boreholes collapsed at various depths where they were grouted with cement to prevent them from collapsing. The borehole logs were prepared for each borehole along with detailed information. [ABSTRACT FROM AUTHOR]