SUBSURFACE MAPS AND THEIR APPLICATIONS IN THE OIL INDUSTRY
Seismic interpretation data and
applications are the key element of a rapid technological evolution in the
remote sensing of the subsurface maps that has resulted in geoscientists
movement from data poor to data rich Stewart, S. A. 1999. The proliferation of subsurface
data has profoundly affected the productivity of oil exploration of industry
within last two decade. This is radically improved of the ability to predict
what lies beneath the earth surface, exploration and production. Log in
construction maps (well) are the supplemented by 2-D data (seismic section and
maps) in the 1950s and by 3-D seismic data from the 1970s onwards Davies R. I.,
Bell B. R. and shoulders S. (2002). However, the evolution of the point are the
essentially dealt with a seismic constructions maps without the used of fourth
dimension-time and the advent of a recent recorded change in the subsurface due
to hydrocarbon extraction overtime. Today, exploration involves the extraction of
more geological information from the seismic signals than ever before (Leadholm
et al 1985).
LIST OF FIGURES
map showing control points before and after contouring.
map showing Drilled thickness vs. actual bed thickness.
map showing Drilled thickness vs. actual bed thickness shown above.
map showing colors units.
A cross sections showing log correlation
& Cross-sectional views of an Isopach map of the thickness of sediments
between an unconformity and basement.
constructions showing a profile and interpretation from mentawai forearc basin
in constructions showing a constant thickness layer in drilling at different
angles by three well (Isopach vs Isochare map
structure and Isopach map.
construction of Isopach/Isochore map.
diagram illustrating correlation of depth lithologies at various depth.
sketch showing map of the study area (modified after fey base et al 1987)
TABLE OF CONTENT
List of figures
Table of contents
1.2 Basic Definition
2.0 Types of subsurface maps
2.1 Structure contour maps
2.2 Isopach maps
2.3 Isochore maps
2.4 Cross sections
3.0 Petrophysics/seismic interpretation data
3.1 Use of seismic in constructing structure
3.2 Use of Log in constructing Isopach/Isochore
4.0 Application of subsurface maps
Subsurface maps: A
case study from Geofizika in Southeastern Cameroon Area.
Subsurface maps are perhaps the most
important vehicle used to explore for undiscovered hydrocarbons and to develop
proven hydrocarbon reserves. However, the subject of subsurface mapping is
probably the least discussed of interpretation and the construction of
structure/Isopach maps, yet most important aspect of petroleum exploration and
development. As a field developed from its initial discovery, a large volume of
well, seismic and production data are obtained. With these data, the accuracy
of the subsurface interpretation is improved through time.
The most accurate interpretation for any
specifics oil and gas field can be prepared only after the field has been
extensively drilled and most of the hydrocarbons have been depleted. However accurate
and reliable subsurface interpretations and maps are required throughout all
exploration and development activities.
Surface mapping: Is a way to visualize various geologic and hydrologic
features in any dimension for a 1-D cross section to a 4-D production map.
Seismic data: is a method of exploration, geophysics that used the
principles of seismology to estimate the properties of the earth subsurface
from reflected seismic waves.
Seismic interpretation: Is the determination of the geological
significance of seismic data.
Seismic stratigraphy: Is a techniques for interpreting
stratigraphic information from seismic data.