PetroTrace – seismic imaging upgrade in PakistanTal Block location map. Source: MOL Group

PetroTrace – seismic imaging upgrade in Pakistan

MOL and PetroTrace collaborate for a two-year 3D onshore seismic processing program in the Tal Block, Pakistan.

The Tal Block is located in the Kohat Plateau, Khyber Pakhtunkhwa Province. MOL Pakistan owns 10.5264% exploration & 8.4210% production phase working interests as an operator.  Block partners are OGDCL, GHPL, POL, and PPL.

So far, nine discoveries have been made in the block, the first in 2002 and the most recent in 2016. Commercial production has commenced from Manzalai, Makori, Makori East, Mamikhel, Maramzai, Makori Deep, Tolanj and Tolanj West fields.

As a result of key development projects, the operated gross production level in Tal Block reached 90 mboepd plateau rate in 2018. TAL block development activities included preparation for the Makori Deep-2 well (spud in Q2), planning for the Maramzai-5/Mardankhel-4 well and progressing with the tie-in of Mardankhel 3 well, where commissioning is expected in Q3 2019.

The two-year program comprises the reprocessing of eight legacy 3D land surveys, a total 2993 km2, with two new 3D acquisitions, for additional 730 km2. The scope includes time reprocessing from raw data, pre-stack time migration, Common Reflection Angle Migration (CRAM) depth imaging, and Diffraction Imaging.

Tal Block, Pakistan.

The aim is that, through CRAM, according to PetroTrace, there will be an improvement in seismic imaging in an onshore foothill area characterised by challenging topography, complex over-thrusting, velocity inversions and data with locally-limited signal quality.

CRAM-based Diffraction Imaging will be deployed over prospects to help image discontinuities (e.g. faults) not fully resolved by standard seismic processing, and to de-risk fracturing at the limestone target reservoirs.

Comparison of KPSDM (left) with CRAM (right); raw seismic images obtained with the same velocity model, pre-migration input, and no post-migration processing. CRAM allows an improved subsurface illumination and seismic imaging, even with steep dips and strong velocity contrasts. Source: PetroTrace

A detailed description of the CRAM technology can be found in GEO 04 magazine.