Abstract:
Unconventional reservoirs are fine-grain sedimentary rocks, rich in organic
shale having trap gas considered a source, reservoir, and seal rock. Shales can be a
good reservoir despite having low porosity and permeability and it can be a tempting
target for hydraulic fracturing, exploration industries target those fine-grained
sedimentary rocks units that may serve as oil/gas reservoirs, thereby comprising of
unconventional energy resources throughout the world. TOC content and brittle
indices of Shinawari Formation were investigated in the research area of Chanda Oil
Field situated in Shakardara, district Kohat, Khyber Pakhtunkhuwa, to predict the
capability for unconventional hydrocarbon potential. TOC values gained through
Schmoker and Passey methods from interpreting the logs showed that there is
variation in the organic richness of Shinawari Formation. TOC values range from 0.2
to 2.4% suggest that Shinawari shale values lie in poor to good source rock and
vitrinite values range between 1.16 to 1.35% suggest that Shinawari Formation is
thermally mature to produce hydrocarbons. The Brittleness Index (BI) was calculated
based on calibrated elastic parameters ranging from 0.3 to 0.56Pa for Chanda-01 and
0.3 to 6.4Pa for Chanda Deep-01. Brittle (BI>0.4Pa) and ductile (BI<0.4Pa) sections
were identified based on BI for the optimization of hydraulic fracture treatment. The
results extracted from the investigation of Shinawri Formation classify the intervals in
the brittle-ductile zone thus making it a suitable target for hydraulic fracturing.
