Microseismic - a Geophysical measurement for the Engineer

By Kash Kashikar 
VP, Completions Evaluation, MicroSeismic, Inc.

Microseismic monitoring is the singular technology that provides measurement of fracture propagation away from the borehole. The process of hydraulic fracturing generates stress in rocks which is released in the form of fracturing, failure and movement along pre-existing structures. This stress release generates seismic waves that propagate outward from the source. These seismic waves are detected by an array of surface or down-hole geophones. The recorded signals are processed to determine the sub-surface location of the failure source. As such microseismic is principally a geophysical measurement. A lot of focus, research and engineering has been applied and continues to be applied to improve the geophysical understanding and rigor of the measurement.

One of the reasons for monitoring microseismic activity is to gain a better understanding of the results of hydraulic fracturing. There is a need to understand the efficiency and effectiveness of the realized fracture geometry. To fully optimize the completion and hydraulic fracture treatment it is important to understand various aspects of fracturing treatment such as differentiating propped and un-propped fractures, fracture growth and geometry, fracture overlap between stages and wells, stress shadowing effects, and treatment efficiency. These are primarily engineering questions. The challenge then for the industry is to translate a geophysical measurement into engineering answers. I have asked myself many times – how can we make a geophysical measurement a tool for the completion engineer, reservoir engineer and production engineer? Since microseismic is the only measurement away from the wellbore, how can microseismic become the measurement of choice for the engineer to help him/her improve the completion and maximize recovery from every well?

Most of the analysis using microseismic data to-date is qualitative and has provided limited value in optimizing completions. Today fracture evaluation is performed using various simulation techniques; geo-mechanical modeling, stochastic fracture modeling, reservoir simulation and history matching. These tools use microseismic data to qualitatively calibrate the model –trying to gain an understanding of the underlying fracture properties. I believe we need new methods that combine contextual information such as geology, well logs, treatment data, etc. with deterministic analysis of the microseismic measurements to gain a deeper level of understanding.

MicroSeismic, Inc.’s Completions Evaluation Services aim to do just that. This distinct process of Completions Evaluation consists of a workflow and tools to perform diagnostic analysis of microseismic data, enabling accurate evaluation of the fracture treatment. It is designed to precisely characterize the fracture network growth and complexity, while providing a methodology to evaluate the wellbore spacing, stage lengths, cluster spacing, and treatment parameters. It provides a framework and work-flow to answer critical questions that are relevant to the engineer.

At Microseismic Inc., our focus is to help customers design, monitor and optimize stimulation treatment and better understand the interaction between the reservoir, the operation and its impact on field and reservoir economics. I look forward to working closely with our customers to deliver a better frac.