Brittleness index analysis of coal samples

• Autorzy: Wu Haibo , Zhang Pingsong , Dong Shouhua , Huang Yaping , Zhang Min

Identyfikatory

DOI

10.1007/s11600-019-00291-5

• Języki publikacji: EN

Abstrakty

EN

The brittleness index (BI), which serves as a key reference for reservoir fracturing, is also an important quantitative index for the evaluation of coal-bed methane (CBM) reservoirs. To address the lack of research regarding this application of the BI, we measured the ultrasonic wave velocity of 10 coal samples collected from the Qinshui Basin, China. We then calculated the BI in three test directions, i.e., BI(90°), BI(45°), and BI(0°), as well as the BI anisotropy value (ABI) using the dynamic elastic method. Analysis of the calculated results showed that BI(90°) generally had the highest values and that BI(45°) was close to BI(0°). The ABI showed a positive correlation with the dynamic Young’s modulus anisotropy value, dynamic Poisson’s ratio anisotropy value, S-wave velocity anisotropy value, and the ratio of P-wave and S-wave velocity anisotropy values. However, the ABI had an unclear correlation with the P-wave velocity anisotropy value. Further analysis of the correlation between the BI and two other reservoir parameters (coal structure type and fracture development) revealed that samples with high BI values generally corresponded to primary or fragmented types of coal and also had low Poisson’s ratios, which indicates undeveloped fractures, while samples with low BI values corresponded to granulated types of coal and had high Poisson’s ratios, which indicates developed fractures. We investigated these correlations in order to understand the multiparameter constraints and their combined application in brittleness evaluations, which could reduce risk and improve the precision of ideal brittleness identification in CBM reservoirs.

Słowa kluczowe

EN

ultrasonic wave; anisotropy value; coal structure; fracture development; dynamic elastic parameters

PL

fala ultradźwiękowa; wartość anizotropii; struktura węgla

• Wydawca: Instytut Geofizyki PAN ; Springer
• Czasopismo: Acta Geophysica
• Rocznik: 2019
• Tom: Vol. 67, no. 3
• Strony: 789--797
• Opis fizyczny: Bibliogr. 26 poz.

Twórcy

autor

Wu Haibo

• School of Earth and Environment Anhui University of Science and Technology Huainan People’s Republic of China

autor

Zhang Pingsong

• School of Earth and Environment Anhui University of Science and Technology Huainan People’s Republic of China

autor

Dong Shouhua

• School of Earth and Environment Anhui University of Science and Technology Huainan People’s Republic of China

autor

Huang Yaping

• School of Resources and Geosciences China University of Mining and Technology Xuzhou People’s Republic of China

autor

Zhang Min

• Key Laboratory of Geotechnical Mechanics and Engineering of the Ministry of Water Resources Changjiang River Scientific Research Institute Wuhan People’s Republic of China

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Uwagi

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2020).