Subsurface deformation is observed during pumping of some hydrocarbon fields. Deformation features include subsidence centered on the field and subsidence-related centripetal horizontal displacements and faulting. Focal mechanisms yield reverse movements on steeply dipping faults. In our sand-silicone analogue model, the reservoir is represented by a latex balloon or by undercompacted ground sand. Deflation of the reservoir results in formation of steeply dipping reverse faults bounding a downward-opened cone. The cone moves downward to follow the reservoir contraction. Faults along the cone are straight beneath a thick reservoir cover and tend to curve upwards with decreasing cover. Our results, similar to natural structures observed around magma chambers, allow us to reinterpret Paul Segall's numerical model of poroelastic stresses caused by changes in the distribution of pore fluids and draw a new pattern of active faults.

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