- Tytuł:
-
Zmienność ilości i składu gazów pochodzących z degazacji rdzeni skalnych w profilu geologicznym otworu z obszaru LGOM
Variability of the amount and composition of gases from the rock cores degassing in the geological profile of the borehole from the LGOM area - Autorzy:
-
Kania, Małgorzata
Janiga, Marek
Wciślak, Agnieszka - Powiązania:
- https://bibliotekanauki.pl/articles/1834131.pdf
- Data publikacji:
- 2020
- Wydawca:
- Instytut Nafty i Gazu - Państwowy Instytut Badawczy
- Tematy:
-
gaz desorbowany
gaz resztkowy
skład molekularny
właściwości petrofizyczne
profil geologiczny
LGOM
desorbed gas
residual gas
molecular composition
petrophysical properties
geological profile
Legnica-Głogów Copper District - Opis:
- The main objective of the research was to determine the amount and chemical composition dependence of gases formed during the degassing process of lithologically and petrophysically varied rocks in reference to the geological profile of the borehole. In the case of copper-bearing formations, determining this type of regularity for different types of rocks will make it possible to predict places and directions of gas exhalation. This may contribute, in the future, to maintaining safety in mines. The subject of the research were rock samples from a selected vertical borehole within copper-bearing formation from the southern part of the Fore-Sudetic Monocline. The samples collected for testing represented the following lithological series: red and grey sandstone, dolomite, anhydrite and rock salt. In order to assess the gas-bearing capacity of rocks with different lithofacial structure, the molecular composition and the amount of desorbed and residual gases were tested within selected vertical well. In addition, all core samples were subjected to porosimetric and permeability tests to evaluate the basic petrophysical parameters. Based on the obtained results, it was found that the amount of evaporated residual gas in the whole area of the borehole profile correlates perfectly with petrophysical properties, and more specifically with the values of total porosity. Samples from the sandstone series (both red and grey sandstone) are characterized by the highest total porosity reaching almost 25% and in these rock pores, the largest amounts of residual gas were accumulated and closed. Slightly smaller amounts of gas were separated during the degassing process from the limestone dolomite sample, taken from the depth of 10.00 m with a relatively high total porosity of 7.3%, and even smaller from the depth of 8.35 m. The amount of residual gas for rock salt (Na1) and for anhydrite samples (A1d) remained significantly lower. Large amounts of gas separated from the pore space of cores during the degassing process are associated with a high content of excess nitrogen. The largest amounts were separated from a series of sandstones and from a sample of dolomite, taken from a depth of 10.00 m, i.e. from cores with high total porosity. Additionally, anomalously high values of excess nitrogen in desorbed gas were found in the anhydrite sample, taken from a depth of 52.00 m (with relatively low porosity). The presence of excess nitrogen in this sample can be explained by selective gas adsorption during long-distance migration, as well as the possibility of forming of local gas traps.
- Źródło:
-
Nafta-Gaz; 2020, 76, 1; 3-11
0867-8871 - Pojawia się w:
- Nafta-Gaz
- Dostawca treści:
- Biblioteka Nauki
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