Properties of Channel and Evolutions of Fluvial Terraces in Odae River Gwang-Ryul Lee* 1 3 OSL 1 MIS 2 2 MIS 3 2 0 205m/ka 0 269m/ka Abstract This study analyzes the properties of fluvial landforms in the upper and lower reaches and investigates the evolutions of stream and fluvial terrace in the Odae river basin. The lower basin of the river that consist of sedimentary rocks resistant to weathering and erosion processes shows higher altitude, relief and slope than the upper basin that consist of granite less resistant to weathering and erosion processes. The average width of river valley at the lower reaches is one-third to the upper reaches and the average width of river channel at the lower reaches is narrower than at the upper reaches. Based on the OSL age dating, the fluvial terrace T1 formed at the temperature-rising period during the late MIS 2 and T2 formed at the middle MIS 3, interstadial period during the last glacial period. Based on the these results, the average incision rates of Odae river are calculated as 0.205m/ka and 0.269m/ka at the upper granite area and lower sedimentary rocks area, respectively. : fluvial terrace, incision rate, difference of bedrocks, width of river valley, structure materials in riverbed 2006 Leopold et al. 1992 Charlton 2008 (Assistant Professor, Department of Geography Education, Teachers College, Kyungpook National University), georiver@knu.ac.kr 224
Summerfield 1991 Strahler and Strahler 2005 Ritter et al. 2006 Plummer et al. 2003 Strahler and Strahler 2005 2006 1 5 000 1 25 000 1 50 000 ArcGIS 1996 1970 1972 1 37 500 1 5 000 1 10km 50 1 2 OSL(Optical Simulated Luminescence) 1 422 1 59 48km 451 86km 2 3 8 5km 8 5km 27 5km 27 5km 2 1 000m 225
이광률 그림 1. 오대천 유역분지의 지형 그림 2. 오대천 유역분지의 지질 -`226`-
1 2 DEM 1 25 000 ArcGIS 227
(m) (m) 767 156 19 7 827 225 27 2 3 4 1 767m 156m 19 7 827m 225m 27 2 2007 228
(m) (m 2 ) (m) (m) 19 136 8 820 582 460 9 34 29 31 085 4 652 294 149 7 32 08 5 1 2km 6 20m 7 2 460 9m 149 7m 1 3 1 5 000 10km 55km 2 5km 2 34 29 32 08 10km 10km 20km 30km 40km 50km 58km 45 25 0 29 21 15 50 68 34 41 60 58 5 7 66 30 19 27 86 9mm 72 3mm 66 9mm 74 8mm 66 2mm 68 5mm 229
(point bar) 50 3 10km 45 30km 66 30km 40km 29 50km 21 27 5km 10km 50km 30km 40km 1 (T1) 9 (T9) 9 8 9 1 10km 37km 1 10km 14 30km 2 13km 16km 17km 20 22km 29km 32 34km 57km 3 15km 20 21km 34km 4 21km 49km 5 20 21km 31 34km 49km 6 31 34km 49km 7 31km 8 34 5km 9 32 5km 15 25km 1 1 230
1 1 2 30 35km 1 21 22km 30 35km 2 231
10 5 10 6 4 1 10 21 14 0 2 14 21 16 6 3 20 9 4 34 0 5 45 6 6 61 2 7 71 5 8 81 0 9 100 5 1 2 20km 20 32km 32 54km 54 57km 57 58km 1 32 54km 1 42 45km 1 11 1 2 232
20km 32 54km 11km 11 20km 2008 11 20km 32 54km 233
1 cobble 1 2 12 (matrix) OSL OD1 1 1 5m 13 2 cobble 1 pebble 1 14 15 2 3 1 OSL OD2 6m 234
15 3 pebble 2 4 OSL 1 OD1 14 000 2 OD2 42 000 1 MIS 2 2 MIS 3 (incision) Schumm 1999 4 1 0 307m/ka 2 0 205m/ka 1 0 536m/ka 2 0 269m/ka 2 1 2 1 2 0 15 0 17m/ka 0 17m/ka 0 17 0 23m/ka 2007 5 2 1 0 3 0 5m/ka 2007 OSL 1 OD1 14 1ka 4 3m 0 307m/ka 7 5m 0 536m/ka 2 OD2 42 3ka 8 6m 0 205m/ka 11 3m 0 269m/ka 235
(km 2 ) (m/ka) 249 4 0 205 452 4 0 269 401 4 0 15 0 17 543 4 0 17 391 4 0 17 0 23 43 4 0 3 0 5 North California Central California Montana 655 0 7 1 8 10 20 4 0 25 1 420 4 0 5 6 9 0 15 0 4 4 10 2007 2007 Wohl 1999 3 1 2 1 2 OSL 1 14 000 MIS 2 2 42 000 MIS 3 1 2 0 26m/ka 18 O 0 46m/ka 18 O 0 06m/ka 4 16 OSL 3 MIS 4 4 MIS 6 5 MIS 6 6 MIS 7 7 MIS 8 236
18 O MIS Bradley 1999 460 9m 149 7m 1 3 34 29m 32 08m 1 9 1 1 15 25km 1 237
21 22km 30 35km 32 54km 11 20km 32 54km OSL 1 MIS 2 2 MIS 3 1 0 307m/ka 2 0 205m/ka 1 0 536m/ka 2 0 269m/ka 1 2 OSL 3 MIS 4 4 MIS 6 5 MIS 6 OSL OSL 1996 1975 1 50 000 1962 1 50 000 1962 1 50 000 2006 2007 42 3 388-404 2007 42 1 27-40 2008 43 6 775-790 2007 14 1 1-15 Bradley, R. S., 1999, Paleoclimatology, Harcourt/ Academic Press. Charlton, R., 2008, Fundamentals of Fluvial Geomorphology, Routledge. Leopold, L. B., Wolman, M. G., and Miller, J. P., 1992, Fluvial Processes in Geomorphology, Dover Publication. Plummer, C. C., McGeary, D., and Carlson, D. H., 2003, Physical Geology, McGraw-Hill, Boston. Ritter, D. F., Kochel, R. C., and Miller, J. R., 2006, Process Geomorphology, Wm. C. Brown. Schumm, S. A., 1999, Cause and controls of channel incision, in Darby, S. E. and Simon, A.(eds.), Incised River Channels: Processes, Forms, Engineering and Management, John Willey & 238
Sons. Strahler, A. and Strahler, A., 2005, Physical Geography, John Willey & Sons. Summerfield, M. A., 1991, Global Geomorphology, Prentice Hall, London. Wohl, E. E., 1999, Incised bedrock channels, in Darby, S. E. and Simon, A.(eds.), Incised River Channels: Processes, Forms, Engineering and Management, John Willey & Sons. 702-701 georiver@knu.ac.kr 053-950-5859 Correspondence: Gwang-Ryul Lee, Department of Geography Education, Teachers College, Kyungpook National University, Sankyuk-dong, Buk-gu, Daegu, 702-701, Korea (e-mail: georiver@knu.ac.kr, phone: +82-53-950-5859) 239