SCATTERING BY A DIELECTRIC CYLINDER FOR SEABED LOGGING A MATHEMATICAL MODELING APPROACH

A method of predicting hydrocarbon reservoirs by using seismic survey and
analysis has been implemented over decades. This method has shown pretty good
approach of locating the presence of hydrocarbon layer especially in vertical
dimension (thick well). The problem is that this method is not quite suitable for
locating the hydrocarbon layer in lateral dimension (thin layer). Engineers came up
with technique called Seabed Logging to complete the technique. It uses the fact that
the hydrocarbon layer has much higher resistivity than its surroundings. The
objective of this Final Year Project is to study and simulate one way of doing Seabed
Logging by analyzing the direct wave and the scattered wave from the hydrocarbon
layer. An Oil and Gas Journal by Statoil published in 2002 is studied and referred as
the main source. A solution of scattering by dielectric cylinder of arbitrary cross
section shape published by Jack H. Richmond in his IEEE Transactions on Antennas
and Propagation journal is also employed. Mathematical model is used as
approximation since it is difficult and expensive to do experiment or to get the exact
complete data of reservoir maps and structures. The scope of this project is limited to
combining these techniques to calculate the direct wave and the wave scattered from
the hydrocarbon layer modeled as dielectric cylinder. By working inversely, the
signal received from the antennas is analyzed to yield information about the
characteristics of the seabed and the hydrocarbon layer. The contrast between the
hydrocarbon layer (relatively high resistivity) and seabed (relatively low resistivity)
gives different wave responses and provides information of the presence of
hydrocarbon reservoir beneath seabed. Combining the seismic technique and Seabed
Logging would yield a higher preciseness in predicting and locating the presence of
hydrocarbon reservoirs and thus reducing the costs of drilling uneconomical or dried
well.