Abstract
This study is aimed to identify hydrocarbon-bearing zones and mapping of lithofacies in productive zones
with the help of petrophysical logs. We have followed a systematic petrophysical examination of three
wells Sawan-01, Sawan-05 and Sawan-07. Four gas-bearing zones have been identified in Cretaceous
sands of Lower Goru Formation. Petrophysical logs are utilized for discrimination of lithological,
porosity and fluid based characteristics of productive sand packages out of thick interbedded shales. The
low response of Gamma Ray (GR) log discriminates sandstone beds from shale in the understudy zones.
GR log also contributed to know the lithofacies distribution in the suspected productive gas zones (PGZ)
which suggest the depositional environment of Cretaceous sands. The plots of neutron porosity (NPHI)
and bulk density (RHOB) show the sampled point data density across the sandstone axis on NPHI-RHOB
cross plots which validate the lithology and gas-presence in the reservoir zones. The reservoir traits
(shale content, effective porosity, water saturation and respective gas potential of the zones) are
estimated and ranked, accordingly. The best productive gas zone is identified in Sawan-5 well based on
values of hydrocarbon saturation and effective porosity that is 0.86 % and 0.13% respectively
M.J. Khan, U. Shakir, M.F. Mahmood, R. Hussain, S.R.F. Bukhari, M. Khaskheli. (2020) Petrophysical Analysis to Map Geological Significance of Sawan Gas Field, Sindh, Pakistan, The Nucleus, Volume-57, Issue-3.
-
Views
754 -
Downloads
66