We propose to identify the Geomechanical causes of the problem encountered during reservoir development and help to identify production and completion guide lines to minimize or to prevent casing failure and to guide future activities. The proposed work consists of taking part in the following work:
1. Field data compilation as provided by CEWELL and Neelam and Heera Asset of ONGC for the specific block, pertinent literature, a survey of structural and casing collapse problems that can be associated with uplift and compaction
2. Building a Mechanical earth model (MEM) for the areas of interest using data from as many wells as available. We will use available data including continuous logs of rock properties, seismic, geological information, stress and pore pressure (leak off data) and direction of stresses in the area. We will also need to identify faults.
a) Set up 1D MEM for several wells
b) Constructing the 3D MEM using all 1D MEM and seismic data
c) Verify the model with existing data and modify as needed
3. Characterization of the reservoir and bounding layers (Geomechanical) and identifying injection/production scenarios conducive to collapse through lab measurements and numerical modeling –
a) Review and analyze Geomechanical information
b) Carry out laboratory tests of core samples
c) Carry out simulation to simulate the observed deformations
The broad scope of work is divided into several missions:
• Study and overview of structural and casing collapse problems that are associated with uplift/compaction
• Development of 1D MEM models
• Development of 3D MEM models
• Seismic inversion and calculation of geo mechanical properties from seismic data
• Models for stress distribution and orientations
• Calculation of strength of rocks and stress measurements between the wells
• Possible deformation maps by way of Brittle-Ductile and intermediate vulnerable layer characterization
• Recommendations to arrest future upliftment/subsidence issues for a new well including specific drilling fluid to be used, method of well casing, method of packers if required in such highly vulnerable Geomechanical cases etc.
• Determining the potential for uplift /compaction for different production/injection scenarios and assessing the possibility of structural problems such as casing collapse using finite element modeling

To estimate the root Geomechanical cause of the problem encountered during the uplift/subsidence at shallow depth of North Heera field in Western Offshore
Scope of Work
The stress distribution associated with injection and depletion can make engineering wells a technical challenge in soft and /water sensitive formations. Well design and completion and operation are significantly impacted by the mechanical behavior of the reservoir. We assume that the upliftment/subsidence might have resulted due to variations in pore pressure associated with fragile rocks. As the casing is cemented to the reservoir, it will follow the local rock displacements and therefore would fail if the imposed strains exceed a critical level. This is a tailor-made extremely short-term project covering a span 10 months where ONGC has sought consultant advice for a burning problem targeting the subsidence and upliftment of offshore wells from IIT Madras.