Use regulation to check fracking impact in oil-producing areas, says don
To address the fear of possible tremors and other safety concerns over impacts of fracking in oil-producing areas, an expert in earthquake and space weather has advocated that long-term micro-seismic monitoring be made mandatory for oil companies operating in regions exposed to such hazards.
Speaking at the technical series of the Nigerian Mining and Geosciences Society (NMGS), Lagos chapter, the guest speaker, Professor Adepelumi Adekunle Abraham, admitted the concerns about seismic hazard associated with stimulation and injection programs in the oil and gas industry in past years.
He however stated that pieces of evidence abound that hydraulic fracking can induce seismicity but not so severe to cause significant damages.
Hydraulic fracturing is the process of creating fissures in underground formations under pressure to allow natural gas to flow. That is, the pressurized injection of a mixture of water, chemicals, and sand in underground formations (rocks with low or no permeability) to allow natural gas and oil to flow more freely from rock pores to a production well.
According to him, there are benefits of increased production of natural gas from hydraulic fracking because hydraulic fracking is the future of the energy industry.
Abraham explained that hydraulic fracturing, along with horizontal drilling technology, helps energy companies to tap previously unobtainable sources of natural gas from shale.
Citing existing research, Abraham noted that pressure depletion of hydrocarbon reservoirs can cause re-activation along fault planes of weakness, resulting in geomechanical hazards such as seismicity.
“As a result of hydrocarbon pore pressure depletion, the reservoir rock starts to compact, causing changes in stresses and strains inside and surrounding the reservoir.
“One of the consequences can be mechanical re-activation of faults, posing several geomechanical hazards such as causing new intra-reservoir hydraulic communication pathways,” he added.
He, therefore, argued for the adoption of an appropriate seismic design code for infrastructural development in regions where hydraulic fracking is taking place, as well as the release of built-up stress in the Gulf of Guinea alongside the axial orientation of extensional stress regimes, which are towards and along the existing fracture zones.