SUMMARY:

This study proposes a workflow, to combine data from logs and cores to establish information of exploratory and production interest, which allows visualizing the results of the integration of geochemistry data with geomechanics in gas or petroleum prospects in shales (Shale Gas or shale oil). Correlation was performed by conventional statistical analysis. The laboratory data used for geochemistry were organic content measurements TOC, Tmax, grain density, S1, S2 and S3. The geomechanical parameters were the compressional velocity Vp, the shear velocity Vs and some static elastic moduli. The logs used were: measurements of gamma ray, sonic, density, neutron porosity and resistivity. Then parameters such as: dynamic Young's Modulus (E), dynamic Poisson Ratio (ν), organic TOC content (Passey, Tristan and regression methods) and fragility (Rickman) were calculated. Correlation was performed using statistical correlation methods (regression, correlation coefficient analysis, principal component analysis, etc.) and combination of variables according to the literature review, for example, TOC vs Young's Modulus, TOC vs Poisson ratio, TOC Vs Brittleness.

The trend observed in the behavior of the Young's Module (E) with respect to the organic content (TOC) follows an inverse relationship. For the data from the Colombian wells examined this relationship is true in most cases.

The analysis of the data does not provide a clear behavior pattern, so there is not a good understanding of the effect of the organic matter content with respect to the Poisson ratio. The same situation was found in the literature review.

Fragility is a parameter that is related in a complex way to lithology, mineral composition, amount of organic matter, effective stress, reservoir temperature, diagenesis, thermal maturity, porosity and type of fluid (Wang & Reed, 2009). Some authors discard the presence of organic matter, but it is clear that the organic matter is a constituent part of the matrix (especially in shale rocks producing gas or petroleum), the fragility of the rock is affected. It is necessary that mechanical anisotropy is also sensitive to the kerogen content. This situation was observed with data from Colombian wells.

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