Dry Hole Analysis of Indus 1-B Well, Chauspur Area, Middle Indus Basin, Pakistan

Abstract

Purpose of this thesis is to present the dry hole analysis of the well Indus 1-B with the help of 2D seismic interpretation and petrophysical analysis of Indus 1-B and wells which are in the vicinity of the respective arca. Study arca lies in the Middle Indus Basin and located in the southeastern boundary of Indian plate. Geologically, the area is lies in the Panu Aqil Graben with tropical climate. The area is 936km far in the southward direction from Islamabad, whereas from Sukkur it is 70 km away. The ultimate purpose of the dissertation is to explain the subsurface geology with the help of seismic data interpretation and petrophysical analysis which will aide in identifying the reasons behind the well gone dry. Acquired data consists of 3 strike and 5 dip lines and a suit of wireline logs of Indus-1B, Kandra 01, and Qadirpur 03. By using the time-depth chart two horizons have been marked. The area shows the characteristics of normal faulting as it is lying in the extensional regime. With the Interpretation of the seismic lines the structures identified are horst and graben present below Sui Main Limestone. Two way travel time along with depth contours of Indus 1-B have been interpreted in order to get a clear picture of the subsurface lithology and structures, It is shown drilled near crestal position of a subsurface feature mapped as a NNW-SSE trending 4 way dip closed structural high. Which indicates that a structure is present with a vertical relief of around 33m and area calculated is 45 Sq Km. Well data has been used for the purpose of petrophysical analysis in order to recognize the reservoirs potential. For the evaluation of zone of interest, different types of petrophysical properties have been computed which include of volume of shale, volume of clean, neutron-density porosity, average and effective porosity, and saturation of hydrocarbon and saturation of water are made to estimate the zones of interest. Sui Main Limestone and Dungan Limestone are assessed on the bases of caliper, gamma ray, resistiv