TITLE:
Electromagnetic Response Studies of the Antenna for Deep Water Deep Target CSEM Environments
AUTHORS:
Noorhana Yahya, Nadeem Nasir, Majid Niaz Akhtar, Muhammad Kashif, Tanvir Hussain, Hasnah Mohd Zaid, Afza Shafie
KEYWORDS:
Control Source Electromagnetic (CSEM); Seabed Logging (SBL); Antenna; Computer Simulation Technology (CST); Hydrocarbon (HC)
JOURNAL NAME:
Journal of Electromagnetic Analysis and Applications,
Vol.4 No.12,
December
31,
2012
ABSTRACT:
The Controlled Source
Electromagnetic Method (CSEM) is used for offshore hydrocarbon exploration.
Hydrocarbon detection in seabed logging (SBL) is a very challenging task for
deep hydrocarbon reservoirs. The electromagnetic field response of an antenna
is unable to detect deep hydrocarbon reservoirs due to a weak electromagnetic
signal response in the seabed logging environment. This work premise deals with
the comparison of the electromagnetic signal strength of a new antenna with a
straight antenna and the orientation of an antenna for deep target hydrocarbon
exploration. Antenna position and orientation (Tx and Ty)
was studied using Computer Simulation Technology software (CST) for deep
targets in marine CSEM environments. The model area was assigned as (40 ′ 40 km) to replicate the real seabed environment.
From the results, the new dipole antenna shows an 804% and 278% increase in
electric and magnetic field strength than the straight antenna. An electric (E)
and magnetic (H) field component study was done with and without the presence
of a hydrocarbon reservoir. Ex and Hz field component
responses with the new antenna at the1 kmtarget were
measured in a deep water environment. It was analyzed that the antenna shows
53.10% (Ex) and 83.13% (Hz) field difference in deep
water with and without a hydrocarbon reservoir at the30 mantenna position from the sea floor. From the
antenna orientation results, it was observed that, the electric field Ex and magnetic field Hz responses decreased from 18% to 12% and 21% to
16%, respectively but was still able to detect the deep target hydrocarbon reservoir
at the4 kmtarget depth. This EM antenna may open new
frontiers for the oil and gas industry for deep target hydrocarbon detection
(HC).