TITLE:
Structural Investigation for Locating Petroleum Reservoirs Using Geoinformatics in Meyal, Potwar Region, Pakistan
AUTHORS:
Zohaib Fayyaz, Javed Iqbal, Ahsan Mehboob, Muhammad Affan Sabir, Abdul Jabbar
KEYWORDS:
Seismic Survey, Geographical Information System (GIS), Petroleum Reservoirs
JOURNAL NAME:
International Journal of Geosciences,
Vol.7 No.11,
November
30,
2016
ABSTRACT: Reflection Seismology
technique (Seismic Survey) is widely used around the world to produce a
detailed analogue image of subsurface geological structures. This information
is used by petroleum experts to accurately plan the location of oil wells. Seismic
survey sections and corresponding well logs exhibit different variables like
acoustic impedance of rock, seismic velocity, rock density, porosity, time and
depth that can be manipulated in GIS to infer a subsurface model for stratigraphic
as well as structural interpretations. In recent years, GIS has emerged as a
powerful analytical tool for subsurface mapping and analysis. Petroleum
exploration is a map intensive process that requires the powerful capabilities of GIS. Purpose of this
research is integration of Geographical Information System with Seismic Surveys
for Structural and Stratigraphic Interpretation of subsurface Geology and
locating Petroleum Prospects. In this research work, GIS has been used to
investigate subsurface geological structures and stratigraphy to carefully
analyze the capabilities of GIS for finding new petroleum prospects in active
thrust belt of Meyal, Potwar region, Pakistan. Acquisition of two-dip and three-strike seismic lines is along with well log data,
followed by spatial seismic data processing, development of geophysical data
management interface, interpolation of shot point data, trend surface analysis
and Geostatistical analysis using GIS. Subsurface zones of high, low or null
probability of petroleum accumulation were then, mapped. Finally, GIS based
maps were developed. Geospatial tomography GIS model inferred that study area is
structurally deformed and exhibits excessive geological faults, and structural
traps. With GIS-tomography interpretation
of section 97-MYL-08, a potential oil bearing zone (popup anticline),
bounded by two thrust faults was
observed at almost 3.6 Km depth in Meyal area with average density of about 2.6
gm/cm3. Thrust fault recognized from sharp discontinuity in GIS based survey
raster was encountered at 2.9 Km depth. Structure contour map was developed. It depicted that Chorgali
formation (dolomitic limestone) at 3.68 Km depth was proven to
be reservoir rock in study area. GIS has proved to be a
powerful and efficient subsurface modeling and analytical tool and it should be
integrated with survey based studies for exploration of oil and gas and
investigation of subsurface geological structures.