DOI QR코드

DOI QR Code

Evaluation for Rock Cleavage Using Distribution of Microcrack Spacings (II)

미세균열의 간격 분포를 이용한 결의 평가(II)

  • Park, Deok-Won (Geologic Environment Division, Korea Institute of Geoscience and Mineral Resources)
  • 박덕원 (한국지질자원연구원 지구환경연구본부)
  • Received : 2016.04.11
  • Accepted : 2016.05.02
  • Published : 2016.06.30

Abstract

The characteristics of the rock cleavage in Jurassic granite from Geochang were analysed. The evaluation for the three directions of rock cleavages was performed using the parameters such as (1) frequency of microcrack spacing(N), (2) total spacing(${\leq}1mm$), (3) mean spacing($S_{mean}$), (4) difference value($S_{mean}-S_{median}$) between mean spacing($S_{mean}$) and median spacing($S_{median}$), (5) density of spacing(${\rho}$), (6) difference value between two exponents for the whole range of the diagrams(${\lambda}_H-{\lambda}_L$), (7) mean value of exponent(${\lambda}_M$), (8) mean value of exponential constant($a_M$), (9) difference value between two exponents for the section under the initial points of intersection(${\lambda}t_H-{\lambda}t_L$), (10) mean value of exponent(${\lambda}t_M$) and (11) mean value of exponential constant($at_M$). The results of correlation analysis between the values of parameters for three rock cleavages and those for three planes are as follows. The values of (I) parameters(1, 2, 7 and 8) and (II) parameters(3, 4 and 5) are in orders of (I) H(hardway, (H1 + H2)/2) < G(grain, (G1 + G2)/2) < R(rift, (R1 + R2)/2) and (II) R < G < H. On the contrary, the values of the above two groups(I~II) of parameters for three planes show reverse orders. Besides, the values of parameter $6({\lambda}_H-{\lambda}_L)$, parameter $9({\lambda}t_H-{\lambda}t_L)$, parameter $10({\lambda}t_M)$ and parameter $11(at_M)$ for three planes are in orders of R(rift plane, (G1 + H2)/2) < H(hardway plane, (R2 + G2)/2) < G(grain plane, (R1 + H2)/2), H < G < R, H < R < G and R < H < G, respectively. The values of the above four parameters for three rock cleavages show the various orders of R < H < G, R < H < G, H < G < R and H < G < R, respectively. Meanwhile, the spacing values equivalent to the initial points of contact and intersection between the two directions of diagrams were derived. The above spacing values for three rock cleavages are in order of rift(R1 and R2) < grain(G1 and G2) < hardway(H1 and H2). The spacing values for three planes are in order of rift plane(G1 and H1) < hardway plane(R2 and G2) < grain plane(R1 and H2). In particular, the intersection angles for three rock cleavages and three planes are in order of rift and rift plane < hardway and hardway plane < grain and grain plane. Consequently, the two diagrams of rift(R1 and R2) and rift plane(G1 and H1) show higher frequency of the point of contact and intersection. These characteristics of change were derived through the general chart for three planes and three rock cleavages. Lastly, the correlation analysis through the values of parameters along with the distribution pattern is useful for discriminating three quarrying planes.

거창지역의 쥬라기 화강암에서 발달하는 결의 특성을 분석하였다. 3개 면, 3개 결에 대한 평가는 (1) 미세균열의 간격의 빈도수(N), (2) 총 간격(${\leq}1mm$), (3) 평균 간격($S_{mean}$), (4) 평균 간격과 중앙 간격($S_{median}$) 사이의 차이값($S_{mean}-S_{median}$), (5) 간격의 밀도(${\rho}$), (6) 도표의 전체구간에 대한 두 지수 사이의 차이값(${\lambda}_H-{\lambda}_L$), (7) 지수의 평균값(${\lambda}_M$), (8) 지수의 상수의 평균값($a_M$), (9) 최초 교차점 이하의 구간에 대한 두 지수 사이의 차이값(${\lambda}t_H-{\lambda}t_L$), (10) 지수의 평균값(${\lambda}t_M$) 및 (11) 지수의 상수의 평균값($at_M$)과 같은 파라미터를 이용하여 수행하였다. 3개 결 그리고 3개 면에 대한 파라미터의 값 사이의 상관성 분석의 결과는 다음과 같다. (I) 파라미터(1, 2, 7 및 8) 및 (II) 파라미터(3, 4 및 5)의 값은 (I) H(3번 결, (H1 + H2)/2) < G(2번 결, (G1 + G2)/2) < R(1번 결, (R1 + R2)/2) 및 (II) R < G < H의 순서이다. 반면에 3개 면에 대한 상기 두 그룹(I~II)의 파라미터의 값은 역순을 보여준다. 그 외에도, 3개 면에 대한 파라미터 $6({\lambda}_H-{\lambda}_L)$, 파라미터 $9({\lambda}t_H-{\lambda}t_L)$, 파라미터 $10({\lambda}t_M)$ 및 파라미터 $11(at_M)$의 값은 각각 R(1번 면, (G1 + H2)/2) < H(3번 면, (R2 + G2)/2) < G(2번 면, (R1 + H2)/2), H < G < R, H < R < G 및 R < H < G의 순이다. 3개 결에 대한 상기 네 파라미터의 값은 R < H < G, R < H < G, H < G < R 및 H < G < R의 다양한 순을 각각 보여준다. 한편, 두 방향의 도표 사이의 최초 접촉점 및 교차점에 해당되는 간격값을 도출하였다. 3개 결에 대한 상기 간격값은 1번 결(R1 및 R2) < 2번 결(G1 및 G2) < 3번 결(H1 및 H2)의 순이다. 3개 면에 대한 간격값은 1번 면(G1 및 H1) < 3번 면(R2 및 G2) < 2번 면(R1 및 H2)의 순이다. 특히 3개 결과 3개 면에 대한 교차각은 1번 결 및 1번 면 < 3번 결 및 3번 면 < 2번 결 및 2번 면의 순이다. 따라서, 1번 결(R1 및 R2) 및 1번 면(G1 및 H1)의 두 도표는 보다 높은 접촉점 또는 교차점의 빈도수를 보여준다. 이러한 변화 특성은 3개 면 및 3개 결의 종합도를 통하여 도출하였다. 마지막으로, 분포 형태와 함께 파라미터의 값을 통한 상관성 분석은 3개 채석면의 판별에 유용하다.

Keywords

References

  1. Baecher, G.B., Lanney, N.A., and Einstein, H.H., 1978, Statistical description of rock properties and sampling. 18th US symposium on rock mechanics.
  2. Barton, C.A. and Zoback, M.D., 1992, Self-similar distribution and properties of macroscopic fractures at depth in crystalline rock in the Cajon Pass Scientific Hole. Journal of Geophysical Research, 97, 5181-5200. https://doi.org/10.1029/91JB01674
  3. Bloomfield, J., 1996, Characterization of hydrogeologically significant fracture distributions in the Chalk: an example from the Upper Chalk of southern England. Journal of hydrology, 184, 355-379. https://doi.org/10.1016/0022-1694(95)02954-0
  4. Dunne, J.A., Williams, R.J., and Martinez, N.D., 2002, Food-web structure and network theory: The role of connectance and size. Proceedings of the National of Sciences of the United States of America (PNAS), 99, 12917-12922.
  5. Freire-Lista, D.M. and Fort, R., 2015, Anisotropy in Alpedrete granite cutting (Rift, Grain and Hardway directions) and effect on bush hammered heritage ashlars. Geophysical Research Abstracts, 17, EGU2015-9426-1, EGU General Assembly.
  6. Gale, J.E., Schaefer, R.A., Carpenter, A.B., and Herbert, A., 1991, Collection, analysis, and integration of discrete fracture data from the Monterey Formation for fractured reservoir. SPE Annual Technical Conference and Exhibition Formation Evaluation and Reservoir Geology.
  7. Galla, B.L., Tshosoa, G., Dymentb, J., Kampunzuc, A.B., Jourdand, F., Feraudd, G., Bertrande, H., Aubourgf, C., and Vetela, W., 2005, The Okavango giant mafic dyke swarm (NE Botswana): its structural significance within the Karoo Large Igneous Province. Journal of Structural Geology, 27, 2234-2255. https://doi.org/10.1016/j.jsg.2005.07.004
  8. Gillespie, P.A., Howard, C.B., Walsh, J.J., and Watterson, J., 1993, Measurement and characterisation of spatial distributions of fractures. Tectonophysics, 226, 113-141. https://doi.org/10.1016/0040-1951(93)90114-Y
  9. Gross, M.R. and Engelder, T., 1995, Strain accommodated by brittle failure in adjacent units of the Monterey Formation, U.S.A.: scale effects and evidence for uniform displacement boundary conditions. Journal of Structural Geology, 17, 1303-1318. https://doi.org/10.1016/0191-8141(95)00011-2
  10. Kim, D.H., Hwang, J.H., Park, K.H., and Song, K.Y., 1998, Geological report of the Pusan sheet (1:250,000). Korea Institute of Geology, Mining and Materials (KIGAM), 62p
  11. Kim, Y.K. and Ro, B.D., 1989, Mechanical properties of discontinuous rocks in Upper Kyeongsang Supergroup. Journal of the Geological Society of Korea, 25, 392-404.
  12. Miller, N.C., 1993, Predicting flow characteristics of a lixiviant in a fractured crystalline rock mass. Report of investigations 9457, US Bureau of Mines, 24.
  13. Olson, J.E., Qiu, Y., Holder, J., and Rijken, P., 2001, Constraining the spatial distribution of fracture networks in naturally fractured reservoirs using fracture mechanics and core measurements. Society of Petroleum Engineers(SPE). SPE annual technical conference and exhibition, New Orleans, Louisiana, SPE 71342.
  14. Park, D.W., 2007, Orientations of vertical rift and grain planes in Mesozoic granites, Korea. The Journal of the Petrological Society of Korea, 16, 12-26.
  15. Park, D.W., 2011, Characteristics of the rock cleavage in Jurassic granite, Hapcheon. The Journal of the Petrological Society of Korea, 20, 219-230. https://doi.org/10.7854/JPSK.2011.20.4.219
  16. Park, D.W., 2015a, Characteristics of the rock cleavage in Jurassic granite, Geochang. The Journal of the Petrological Society of Korea, 24, 153-164. https://doi.org/10.7854/JPSK.2015.24.3.153
  17. Park, D.W., 2015b, Evaluation for rock cleavage using distribution of microcrack lengths. The Journal of the Petrological Society of Korea, 24, 165-180. https://doi.org/10.7854/JPSK.2015.24.3.165
  18. Park, D.W., 2016, Evaluation for Rock Cleavage Using Distribution of Microcrack Spacings (?). The Journal of the Petrological Society of Korea, 25, 13-27. https://doi.org/10.7854/JPSK.2016.25.1.13
  19. Park, D.W., Kim, H.C., Lee, C.B., Hong, S.S., Chang, S.W., and Lee, C.W., 2004, Characteristics of the rock cleavage in Jurassic granite, Pocheon. The Journal of the Petrological Society of Korea, 13, 133-141.
  20. Park, D.W., Seo, Y.S., Jeong, G.C., and Kim, Y.K., 2001, Microscopic analysis of the rock cleavage for Jurassic granite in Korea. The Journal of Engineering Geology, 11, 51-62.
  21. Pearce, M.A., Jones, R.R., Smith, S.A.F., and McCaffrey, K.J.W., 2011, Quantification of fold curvature and fracturing using terrestrial laser scanning. AAPG Bulletin, 95, 771-794. https://doi.org/10.1306/11051010026
  22. Priest, S.D. and Hudson, J.A., 1976, Discontinuity spacings in rock. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 13, 135-148.
  23. Rives, T., Razack, M., Petit, J.P., and Rawnsley, K.D., 1992, Joint spacing: analogue and numerical simulations. Journal of Structural Geology, 14, 925-937. https://doi.org/10.1016/0191-8141(92)90024-Q
  24. Rouleau, A. and Gale, J.E., 1985, Statistical characterization of the fracture system in the Stripa Granite, Sweden. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 22, 353-367. https://doi.org/10.1016/0148-9062(85)90001-4
  25. Sanderson, D.J., Roberts, S., Gumiel, P., and Greenfield. C., 2008, Quantitative analysis of tin- and tungsten-bearing sheeted vein systems. Economic Geology, 103, 1043-1056. https://doi.org/10.2113/gsecongeo.103.5.1043
  26. Segall, P., 1984, Formation and growth of extensional fracture sets. Geological Society of America Bulletin, 95, 454-462. https://doi.org/10.1130/0016-7606(1984)95<454:FAGOEF>2.0.CO;2
  27. Seok, C.K. and Kim, Y.K., 1991, Discontinuous properties of Jurassic and Cretaceous granites, Korea. Journal of the Geological Society of Korea, 27, 123-135.
  28. Streckeisen, A.L., 1976, To each plutonic rocks and its proper name. Earth-science reviews, 12, 1-33. https://doi.org/10.1016/0012-8252(76)90052-0

Cited by

  1. Evaluation for Rock Cleavage Using Distribution of Microcrack Spacings (III) vol.25, pp.4, 2016, https://doi.org/10.7854/JPSK.2016.25.4.311