Page 23: of Offshore Engineer Magazine (Jan/Feb 2025)

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3D VIEW OF SLEIPNIR DATA

Using an oil and gas seismic survey system for CCS monitoring is like using a military tank

URPRISE for daily commuting.

– Frank Chen,

Senior Solutions Architect,

TAINTY

Ovation Data hysicists at Los Alamos National Laboratory that are not detected in seismic surveys and therefore can- recently pointed out that current physical not be accurately included in simulations.

models of sequestered CO2 don’t properly “This isn't to say that geologists and reservoir engineers account for the elasticity of a rock when it is haven't done their part well,” says Frank Chen, Senior So- saturated by a ?uid. They have developed a lutions Architect at Ovation Data. “The challenge lies in

P new model they hope will make monitoring of CCS sites the fact that the input models, heavily controlled by only more reliable. a few wells, often need more details of geological heteroge-

Physics models such as the Biot-Gassmann equation, neity in areas without well control.” and the newer model from Los Alamos, along with others 4D seismic, which compares time-lapse differences in such as Darcy’s Law, are used to simulate CO2 behavior. seismic surveys to capture snapshots of the CO2 plume

The aim is to avoid “subsurface surprises” – ?nding seques- front over time, is perhaps the only physical measurement tered CO2 in unexpected places. that can 'directly measure' the CO2 plume front laterally,

The CCS industry relies on geological and ?ow simu- especially far from the injection well location, says Chen.

lation models to predict CO2 plume development over “4D seismic offers detailed mapping of the CO2 plume decades. The surprise usually turns out to be signi?cant front. Moreover, it is an invaluable communication tool permeability features, such as invisible faults or barriers, that bridges understanding among operators, regulators january/february 2025 OFFSHORE ENGINEER 23