Study of the petrology of the shale rock from the Parana basin

Abstract

In the present work, the characteristics of shale rock, collected in the surrounds of Limeira, in the interior of São Paulo, were studied. Shales are rocks formed by the consolidation of layers of clay, silt or mud, and are composed of minerals derived from mechanical abrasion materials, weathering final product and chemical and/or biochemical additions [1]. Shales are mostly fine granules, susceptible to the mineralogical rearrangement, and their chemical composition is quite varied due to the geomorphology and the tectonism undergone by the sedimentary basins. They are impermeable structures, formed by the consolidation of layered clay with thin laminations. Because of these characteristics presented, together with the decline of petroleum production, a growing interest in the better understanding and knowledge of the physical-chemical properties of the interior of shale rocks has been demonstrated. In this work, different methodologies were used to characterize them, using the Gamma Ray Computed Industrial Tomography technique along with other complementary procedures, such as Scanning Electron Microscopy (SEM), X-Ray Fluorescence and X-Ray Diffraction. Several characteristics have been studied, such as the analysis of the particle morphology, the contrasts and distributions of these particles in the internal structure of the rock, identification of the types of elements present (quantitative analysis), as well as establishing a proportion in which each element is present in the mineral through its crystalline structure and obtaining images of the rock internal structure.