Fig. 1. The locality of study area in the (a) tectonic map of Korea (1: 1,000,000) (KIGAM, 2001), (b) Daejon (left D) (Lee et al., 1996) and Andong (right A) (Hwang et al., 1996) sheets (1: 250,0000), and (c) Muju (left M) (Hong et al., 1980) and Seolcheon (right S) (Yun and Park, 1968) sheets (1: 50,000). For detailed explanation, see these sheets and map and https://mgeo.kigam.re.kr/map/geology. For reference, the boundary (bdy) of Ogcheon Belt (OB) and Ryeongnam Massif (RM) and the shear zones (SZ) on the 1: 250,000 and 1: 50,000 geological sheets modified after the 1: 1,000,000 tectonic map of Korea.
Fig. 2. Geological map of the study area [modified from Yun and Park(1968) and Hong et al.(1980)].
Fig. 3. Outcrop photographs of major rock structures deformed in the Dn-1 and Dn phases. (a) Fn fold folding Sn-1 foliation (No. 136: banded biotite gneiss). (b) Sn-1 foliation and FnAp refolded by Fn+1 fold (No. 137: banded biotite gneiss). (c) A-type Fn fold, (d) sheath Fn fold (arrow marks) (No. 113: crystalline limestone). Ap: fold axial plane, Ax: fold axis, Ln: stretching lineation. For detailed explanation and outcrop sites, see the text and Fig. 4a.
Fig. 5. Outcrop photographs of major rock structures deformed in the Dn+1 and Dn+2 phases in the crystalline limestone [(a-e) No. 111, (f) No. 113, (g) No. 110 outcrop sites]. (a) Whole photograph, and (b-e) partial enlarged photographs of (a) [(a) S-shaped asymmetric Fn+1 major fold folding the Sn regional foliation, (b, c) M-shaped symmetric and (d) Z-shaped asymmetric Fn+1 parasitic folds, (e) Sn foliation and Fn+1Ap refolded by Fn+2 fold]. (f) M-shaped symmetric Fn+1 fold. (g) Fn+2 fold folding the Sn foliation. Ap: fold axial plane. For detailed explanation and outcrop sites, see the text and Fig. 4a.
Fig. 6. Outcrop photographs of major rock structures deformed in the Dn+1 phase in the non-crystalline limestone metamorphic rocks. (a) Whole photograph, (b) partial enlarged photographs of (a) (No. 115). (c) Fn+1 box fold (No. 122). For detailed explanation and outcrop sites, see the text and Fig. 4a.
Fig. 8. Stereoplots of the Sn foliation dispersed by Fn+1 folding in the (a) No. 111 (crystalline limestone), (b) No. 113 (crystalline limestone), and (c) No. 115 (banded biotite gneiss) outcrop sites. (d) Stereoplots of the Sn foliation dispersed by Fn+2 folding in the No. 111 (crystalline limestone) outcrop site.
Fig. 4. (a) Orientations of the Dn-1 and Dn structural elements. (b-e) Stereoplots of the (b) Dn-1 and (c-e) Dn [(c) all, (d) crystalline limestone, (e) non-crystalline limestone metamorphic rocks] structural elements. Lowerhemisphere equal-area projection, Numbers (110, 111, 113, 115, 122, 136, 137): outcrop sites. For detailed explanation, see the text.
Fig. 7. (a) Orientations of the Dn+1 and Dn+2 structural elements. Stereoplots of the (b) Dn+1 and (c) Dn+2 structural elements. Lower-hemisphere equal-area projection. For detailed explanation, see the text.
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