Seismic Modeling&Inversion With Petrophysical Analysis Of Miano Area,Central Indus Basin,Pakistan

The aim of this dissertation is to estimate the structural analysis and hydrocarbon potential of Miano area,Central Indus Basin,Pakistan.Study area hosts a number of gas fields with structural and stratigraphic traps.Area is situated in Middle Indus Basin which is a part of an extensional regime showing normal faulting due to the split of the Indian Plate firstly from Africa and then from Madagascar and Seychelles.Miano area recognized as a proven petroleum province which has complex tectonic history.Inversion is carried out for Cretaceous extensional and overprints of Tertiary strike-slip tectonics.The area has prospect with accumulation of hydrocarbons in structural and stratigraphic traps including pinchouts.NW-SE oriented Khairpur and Mari highs are main structural features with impact on the fault system.Sands of Lower Goru of Lower Cretaceous age are performing as a reservoir in the region.Miano has great potential of hydrocarbons for which more exploratory wells are required to be drilled with better insight of structural and stratigraphic traps.Miano prospect area is surrounded by a number of gas fields with the great Mari amongst them.At the time when OMV led joint venture entered the block all fields produced from relatively shallow Tertiary reservoirs.Similar types of structural traps were also expected in Miano area.For the interpretation of the seismic data reflectors were marked based on stratigraphic studies.These reflectors named as Sirki Shale,Habib Rahi,Sui Main Limestone,Ranikot,Upper Goru,Lower Goru,Lower Goru Sand,Chiltan formation initially time sections were prepared,which were converted to depth section to give true subsurface picture.Straight reflectors representing strike line with lacking structures.Dimensional visualization of the prominent reflectors was done,which showed how formations are stratified in the subsurface.In addition,rock properties were also calculated using this data,special concentration was on the porosity of the rocks which further confirmed the reservoir potential.The area is of high interest tectonically which has made it a good prospect area and accumulation of hydrocarbons is due to structural,lithological variation and pinching of strata.Khairpur High and Mari High are providing suitable environment to hydrocarbons.The sands of Lower Goru of Lower Cretaceous are acting as a reservoir in the area.Miano prospect area has a great potential of hydrocarbons and more exploratory wells may be drilled in the future targeting the Lower Goru Sands.Inversion technique is used to calculate impedance from seismic data.In seismic inversion there is an ambiguity seen in transforming impedance values into rock properties like porosity.A good indication of reservoir is when there is a sharp increase in porosity and low impedance detected.This phenomenon also represents the occurrence of shale because shale has an excellent porosity and low impedance like reservoir rock.The study is revolving around to separate those two different features means to identify reservoir and non-reservoir rocks by cross plot analysis.The technique is used to resolve this ambiguity in which gamma ray values are imbedded during porosity prediction from impedance.This technique prevents from misleading and helps a lot in isolating the points which come from the shale.To achieve target in the first attempt require high exploration costs.Optimization technology innovate higher-value solutions.Exploration risk is mitigated by reservoir prediction through Inversion technique.It involves the transformation of impedance into quantitative rock properties like porosity,saturation and pore pressure.3D mapping is also done on desired wells including Kadanwar-10,Maino-02,Mian-05,Miano-07,and Miano-09.The technique is established in this research to resolve artefacts in the interpretation for the exploration of hydrocarbon.