Abstract

A key feature of shale reservoirs is their low level of permeability. As a means of producing from these reservoirs, there is a requirement to create hydraulic fractures with highest level of conductivity, but these fractures are subsequently filled with high amounts of fracturing fluid chemicals during hydraulic fracturing and production from shale is impacted by formation damage that results from clay swelling and proppant embedment. The goal of this work is to develop insights into the proppant embedment that results from the mineral composition of the shale following instrumented indentation, Raman spectroscopy technique coupled with modelling approaches. The Caney Shale is an organic-rich, often calcareous mudrock. Many studies have examined the impact that clay has on different kinds of shale productivity but there is currently no data reported on Caney in relation to horizontal drilling. However, there also remains a lack of understanding of the mechanisms involved. While many scholars have investigated the influence that clay has on fracture conductivity, the combination of the use of indentation techniques and Raman spectroscopy coupled with modelling as a means of comprehending shale well production is an area that needs further consideration. Indentation tests were performed on a micro level on drilled rock core specimens as a means of determining the mechanical composition of bulk phases of these multiphase materials. The outcomes of the micro-indentation revealed that the bulk mechanical properties of the shale sample were higher overall. The creep effect impacts the maximum penetration depth and the modulus of elasticity of the shale sample. The variation in mechanical properties can be attributed to the changes in the mineralogical composition and microstructure. We believe that this method can provide an understanding into trends and help connect to field performance that would enable more comprehensive completions and avoid fracture plugging and loss of production.