Interpretation of Geomorphology and Geology using Slope Gradation Map

Transcription

1 Geoinformatics, vol.11, no.1, pp.11-24, 2000 Interpretation of Geomorphology and Geology using Slope Gradation Map Izumi KAMIYA, Takahito KUROKI and Kohei TANAKA Abstract: We produced slope gradation maps, which show dip of ground as gray scale image, from Digital Map 50m Grid (Elevation), precise DEM data covering the whole Japan. We tried to interpret geomorphology and geology using the maps. The maps are useful in interpreting geomorphology of lowlands (terraces), mountains, volcanoes and landslide areas. The maps are also useful in interpreting geology, that is lineaments suggesting tectonic line and fault, and boundary of distribution area of some kinds of rocks. Prewitt type or Sobel type operator is better than Roberts type operator to calculate dip for the interpretation. We compared slope gradation map with other types of map describing topography, that is contour map, DEM image and hill shading map. Slope gradation map is the best among them for interpreting geomorphology and geology. "Brightness," "uniformity," "line intervals," "sharpness" and "directional characteristics" are basic interpretation keys for slope gradation map. "Brain like pattern," interlocking structure of bright lines corresponding to ridges and ones corresponding to valleys on a dark background corresponding to slopes, is one of the most important interpretation key in mountains. In conclusion, slope gradation map is very important material for investigation of geomorphology and geology. Key Words: slope gradation map, interpretation, geomorphology, geology, DEM (DEM), 1997 DEM GIS 1994 (1985) (1992) (1992) * Geographical Survey Institute, 1, Kitasato, Tsukuba, Ibaraki, , Japan. kamiya@gsi.go.jp ** Faculty of Agriculture, Shinshu University, 8034, Minamiminowa, Nagano, , Japan.

2 go.jp/slopemap/index.html 50m /200,000 1 H22 H11H12H13H21H23H31H32 H33SxSy (1) S 2 S = Sx + Sy 2 SxSy Horn(1981) (2)(4)(1991)(3) ( H Sx = ( H Sy = ) ( H 2Dx ) ( H 2Dy ) ) (1) (2) ( H Sx = ( H Sy = ( H Sx = ( H Sy = H + 2H ) ( H 6Dx ) ( H 6Dy ) ( H 8Dx ) ( H 8Dy H + 2H ) ) ) ) (3) (4) DxDy(2)(3)(4) S Roberts Prewitt Sobel Roberts Prewitt Sobel S DxDy ϕ DxDy Dx = N λcosϕdy = M ϕϕ ϕ λ MN 1984 (1994) 50m 2 Roberts 2 Prewitt Sobel Roberts Prewitt Sobel () Dy () H 11 H 12 H 13 H 21 H 22 H 23 H 31 H 32 H 33 Dx 1 H 22 H 11 H 33

3 3 Prewitt (3) UTM 1/200, i 3 3 (a)(b)(b) 3 ''' ' '(1987) ' '' ' (a) Roberts (b) Prewitt (c) Sobel 2 Prewitt Sobel NE-SW Roberts (a) (b) 3 ' '' (1987) (b)

4 4 ' ''' 3.2 gå ' '3.1 ' (1989)(1999)(1987) ' ' ' 3.4 (1980) 5 (1984) (1984)

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6 (1991) 8 (1985) 9092Ma (1985) (1973) (1982) (1991)(1985) (1990) 3.6 í 9 (1992) /25, š 12 (a) 12 (b)dem 12 (c) 12

7 7 7 (1991)

8 8 8 (1985) 10 1/50,000 (1981) 9 (1992) 11

9 9 (d),(e) m 1/25,000 50m m 1/200,000 (a) (d) (b) 50m DEM (e) 1/200,000 (c) DEM 12 1/50,000

10 10 1/25,000 1/2 1/50,000 1/16 1/4 12 (b) 50m 1/100, (b) 1/200,000 1/2 4.2 DEM DEM DEM (d) 12 (d) (d) 12 (e) (d) 50m 3 (b) 50m DEM

11 (a)(b) (c)(d)(e) (f)(g) S (x,y) S(x,y) S(x,y) (a)(b) 13 (f) 5.2 š 13 (b)(c) (c)(d) S(x,y) (a) (b) (c) (d) (e) (f) (g) 13 (a)(b) (b)(c) (c)(d) (c)(d)(e) NNW-SSE (f) (g)

12 12 1 S (x,y) S(x,y) S(x,y) (g) 5.5 š 13 (c)(d) (e) S(x,y) S(x+x,y+y) S(x,y) 5.6 (1) Roberts Prewitt Sobel (2) DEM (3) (4)

13 13 (5) (6) (7) 7 () () Ð (1996) p.657 (1989) pp (1995) (1996) pp (1976) 1:200,000 (1990) Horn, B. K. P.(1981) Hill shading and the reflectance map. Proceedings of the IEEE, vol.69, no.1, pp (1998) pp (1992) vol.3no.1pp (1994) no.37b-1pp (1997) D2-No.46 34p (1999) D2-No.47 32p (1995) vol.6no.2pp (1991) 436p (1973) (1999) vol.72ano.1 pp (1982) (1983) (1987)

14 14 vol.82no.4pp (1987) 119p.4 (1985) pp p (1994) 33 pp (1993) 28 pp (1991) vol.9pp (1980) 1:200,000 (1984) pp.8-13 (1992) no.75pp (1982) no.69 (1984) no.85 (1985) 1:200,000 (1984) 41 vol.34no.2pp (1997) 200p (1991) pp (1999) pp (1985) vol.69pp (1996) 1:200,000 (1988) (1992) 1:200,000 (1972) 1:200,000 (1981) 1:200,000 50m () Roberts Prewitt Sobel DEM