Application of Raman spectroscopy analysis in unconventional natural gas reservoirs – density and pressure dependence on Raman signal intensity

Abstract

According to an EIA reports, it is estimated that shale oil and shale gas resources are located in United States and in 137 shale gas formations in other 41 countries worldwide. Possible resources in these formations include about 345 billion barrels of world shale oil and 7,299 Tcf (trillion cubic feet) of world shale gas (Fig. 1) [1–3]. Furthermore over 85% of global resources of shale gas and over 72% of tight gas are located within fifteen countries. Despite the downturn in the global markets, unconventional natural gas production increased recently. Exploitation of main shale oil and gas basins is still more popular due to the higher reservoir potential and economically feasible drilling and exploitation [4–6]. Due to the energy policy implemented by the Polish government and the downturn in the global oil and gas industry, the situation in the Polish gas market has significantly changed in last few years. According to Polish Geological Survey reports, the number of granted concessions for exploration and exploitation remarkably diminished from January 2012 with only 30 concessions now active. For a better understanding of the current situation in Poland, 115 concessions were active in 2012 and 40 in 2015 [7–10]. However, amongst European countries Poland still has one of the most significant potentials for shale gas exploitation. Poland is in thirteenth position in the world and the first in Europe with the largest resources of shale gas. Given favorable conditions and market trends in the oil and gas industry, Poland could be a leader in the production of shale gas in the mid and long term future due its high-developed scientific and technical experience. The reported Polish shale gas resources could potentially cover demand for natural gas in the region of Central Europe [4].