HISTORY OF EXPLORATION AND PETROLEUM POTENTIAL OF THE LVIV PALEOZOIC TROUGH

Abstract

The article reveals the stages and current state of exploration regarding the oil and gas potential of the Lviv Paleozoic Trough, based on geological and geophysical survey data, drilling results from various well types, and formation testing. The main periods of geological and geophysical study of this region from the 1960s to the 1990s are analyzed. The results of geological and geophysical data interpretation by leading industrial and scientific institutions have been systematized, demonstrating their contribution to the region's development. The transition from regional studies to detailed seismic prospecting is highlighted, which formed the basis for constructing structural maps of the region for the main reflecting horizons within the basement and sedimentary cover. The results of parametric, exploratory, and structural drilling are analyzed, indicating direct evidence of oil and gas presence within various stratigraphic complexes. Significant attention is paid to the evolution of scientific views on the prospects for oil and gas potential in this region. Until the mid-1960s, the primary prospects were associated with the Devonian system. Subsequently, Silurian and Cambrian deposits began to be considered promising. The discovery of the Velyki Mosty and Lokachi fields confirmed the commercial significance of the Devonian complex. Companies that obtained production licenses within this region focused their research on studying the gas potential of Devonian deposits and identifying productive horizons within them. The systematization of long-term research results, reflected in numerous scientific works and industry reports, indicates potential targets within the Lviv Paleozoic Trough. Based on the comprehensive interpretation of geological and geophysical studies, drilling data, and formation testing, productive structures such as Semerynska, Volodymyrivska, Vichynska, Voynytska, Horodynska, Pavlivska, and others can be identified. The directions for drilling new exploration, parametric, and structural wells within the structures of the northern part of the Lviv Paleozoic Trough are outlined as one of the promising targets for increasing the hydrocarbon resource base within the Western Oil and Gas Region. Negative results during exploration and appraisal work in previous years were caused by a combination of factors. The low quality and fragmentation of seismic data, coupled with uneven drilling coverage, led to incorrect interpretations of the geological structure and inaccuracies in determining optimal well locations both within the Lokachi Arch and on adjacent structures. The application of 3D seismic surveys in combination with geological data within the northern part of the Lviv Paleozoic Trough can significantly contribute to minimizing inaccuracies in geological models and identifying deposits. This will facilitate successful subsurface development, ensure commercial profits for oil and gas companies, and, most importantly, meet hydrocarbon demand.