The geochemical composition of oil as a way of checking the quality of hydraulic fracturing

Abstract

© 2020 International Multidisciplinary Scientific Geoconference. All rights reserved. The article describes the results of laboratory measurements of the micro-component composition of the produced oil and the mathematical processing of the obtained values in one of the fields of the Republic of Tatarstan. Vereiskian and Bashkirian horizons were studied, which are quite widespread in the Republic and surrounding areas. The studied horizons lay one above the other in close proximity to each other. The Bashkirian deposits are a massive reservoir, while the Vereiskian deposits have the form of a layer-uplifted deposit. When hydraulic fracturing is carried out on Vereiskian reservoirs, penetration of hydraulic fractures into underlying Bashkirian fractures is possible. Hydraulic fracturing can significantly increase the flow rate of wells developing the Vereiskian horizon, and is a common operation in existing geological conditions. To understand the situation in the well after hydraulic fracturing, it is proposed to study the composition of oil from the reservoirs between which overflows are possible. For this, oil samples are taken from wells operating at target horizons, called reference samples. The characteristic features of each of them are established. Then, oil samples are examined in the wells in which the hydraulic fracturing was performed. In this work, flows between the Vereiskian and Bashkirian strata were established and the share of the contribution of each of these strata to the production of wells was calculated using the developed algorithms based on the methods of mathematical statistics. Additionally, technological difficulties associated with causes of various natures were identified at the reference wells. An individual approach to each such well was made, the history of its work and the well intervention were studied. Separate recommendations are given for wells. Thus, the prospect of using the composition of the produced oil to determine the quality of the hydraulic fracturing work has been considered.