Fig. 1. Sketch of microcracks parallel to the six directions of rock cleavages on rift plane (1), grain plane (2) and hardway plane (3). (a) Photomicrograph of thin section of the Geochang granite cut parallel to three planes. Black, mottled, and white areas represent quartz, feldspar and biotite, respectively. (b) Map of microcracks from total method. (c) Map of microcrack spacings. (d) and (e) Diagram of the six directions of rock cleavages on three planes. The distribution of lengths (d) and spacings (e) of microcracks are shown. The preferred orientation of microcracks in the quartz and feldspar parallel to the six directions of rock cleavages (Park, 2016a, b, c, 2017a, b, c, 2018).
Fig. 2. Diagram illustrating the intersection angle (α-β) and convergence direction (3) between two exponential straight lines aa' (spacing) and bb' (length). α and β (°): slope angles of lines aa' and bb', os and ol: vertical lines to lines aa' and bb', △oaa' and △obb': right-angled triangles.
Fig. 3. The length and spacing-cumulative frequency diagrams for three planes (a, b and c) and three rock cleavages (d, e and f). Symbols of intersection angle (α-β), convergence direction, length of line and right-angled triangle are the same as ones in Table 2 and Fig. 3.
Fig. 4. The length and spacing-cumulative frequency diagram representing the six directions of rock cleavages (H2~R1) in Jurassic Geochang granite.
Fig. 5. Distribution chart for the ratio value with respect to three planes and three rock cleavages. The symbols of parameters are the same as ones in Table 3.
Table 1. The values of parameters related to two exponential straight lines for three planes
Table 2. The values of parameters related to two exponential straight lines for three rock cleavages
Table 3. The comparison of order in magnitude of parameter value among three planes and three rock cleavages
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