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arXiv · 0803.1308

Subsidence and capillary effects in chalks

Pierre Delage·Christian Schroeder·Yu Jun Cui
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Abstract

Based on the concepts of the mechanics of unsaturated soils where capillary phenomena arise between the wetting fluid (water) and the non-wetting one (air), the subsidence of chalks containing oil (non-wetting fluid) during water injection (wetting fluid) is analysed. It is shown that the collapse phenomenon of unsaturated soils under wetting provides a physical explanation and a satisfactory prediction of the order of magnitude of the subsidence of the chalk. The use of a well established constitutive model for unsaturated soils allows a description of the hydro-mechanical history of the chalk, from its deposition to the oil exploitation.

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Pierre Delage, Christian Schroeder, Yu Jun Cui. 2008-03-09. Subsidence and capillary effects in chalks. https://arxiv.org/abs/0803.1308

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