Late Quaternary Slip Rate and Geometric Segmentation of the Northern Ulsan Fault in Southeastern Korea: Insights from Offset Alluvial Fans and Luminescence Dating
1
Division of Earth and Environmental System Sciences, Pukyong National University, Korea (South)
2
Department of Geography, Kyungpook National University, Korea (South)
3
Department of Geography Education, Korea National University of Education, Korea (South)
Submission date: 2026-02-02
Acceptance date: 2026-10-19
Online publication date: 2026-11-04
Publication date: 2026-11-04
Corresponding author
Su-Ho Jeong
Division of Earth and Environmental System Sciences, Pukyong National University, Korea (South)
Division of Earth and Environmental System Sciences, Pukyong National University, Korea (South)
Geochronometria 2026;53(1)
KEYWORDS
TOPICS
ABSTRACT
Constraining the long-term activity of reverse faults in intraplate regions is challenging due to subtle surface expressions and limited paleoseismological records. This study investigates the late Quaternary activity of the Galgok fault (GF), located in the northern part of the Ulsan Fault, through geomorphic mapping and luminescence dating of offset alluvial fan surfaces. Detailed geomorphic analysis identified multiple generations of alluvial fans and fault-related markers, enabling measurement of cumulative vertical offsets. Quartz OSL dating of the Qf2 surface yielded formation ages ranging from 7.6 ± 0.6 ka to 34 ± 3 ka, while K-feldspar pIRIR50,225 dating constrained the older Qf3 surface to 175 ± 6 ka. Vertical slip rates were estimated using Monte Carlo simulations that propagate uncertainties in both offset and age. Based on a cumulative vertical offset of 3.31 ± 0.24 m, late Quaternary time-averaged vertical slip rates range from 0.1 to 0.44 mm/yr, depending on the Qf2 age. Excluding a potentially reworked near-surface sample yields a more conservative range of 0.1 to 0.21 mm/yr. Geometric analysis indicates that the GF constitutes a single geometric segment (4.56 km). These results demonstrate the effectiveness of combining geomorphic markers with luminescence dating for assessing long-term fault behavior in low-strain intraplate settings.
REFERENCES (63)
1.
Boncio P, Liberi F, Caldarella M and Nurminen FC, 2018. Width of surface rupture zone for thrust earthquakes: implications for earthquake fault zoning. Natural Hazards and Earth System Sciences 18: 241–256, DOI 10.5194/nhess-18-241-2018.
2.
Burchfiel BC, Royden LH, van der Hilst RD, Hager BH, Chen Z, King RW, Li C, Lü J, Yao H and Kirby E, 2008. A geological and geophysical context for the Wenchuan earthquake of 12 May 2008, Sichuan, People’s Republic of China. GSA Today (The Geological Society of America) 18(7): 4-11, DOI 10.1130/GSATG18A.1.
3.
Buylaert JP, Murray AS, Thomsen KJ and Jain M, 2009. Testing the potential of an elevated temperature IRSL signal from K-feldspar. Radiation Measurements 44: 560–565, DOI 10.1016/j.radmeas.2009.02.007.
4.
Cheong CS, Hong DG, Lee KS, Kim JW, Choi JH, Murray AS, Chwae U, Im CB, Chang CJ and Chang HW, 2003. Determination of slip rates by optical dating of fluvial deposits from the Wangsan fault, SE Korea. Quaternary Science Reviews 22: 1207–1211, DOI 10.1016/S0277-3791(03)00020-9.
5.
Choi S-J, Jeon JS, Song GY, Kim HC, Kim YH, Choi BY, Chwae WC, Han JG, Ryoo CR, Seon CG, Cho MS, Kim KY, Kim YB, Lee HJ, Shin JS, Lee YS, Kee WS, Lee HK, Song YG, Kim YS, Kang TS, Hong DG and Kim SC, 2012. Active fault map and seismic hazard map. National Emergency Management Agency (NEMA): P205–216 (in Korean).
6.
Clark D, McPherson A, Allen T and De Kool M, 2014. Coseismic surface deformation caused by the 23 March 2012 Mw 5.4 Ernabella (Pukatja) earthquake, central Australia: Implications for fault scaling relations in cratonic settings. Bulletin of the Seismological Society of America 104(1): 24–39, DOI 10.1785/0120120361.
7.
Dawson J, Cummins PR, Tregoning P and Leonard M, 2008. Shallow intraplate earthquakes in Western Australia observed by interferometric Synthetic Aperture Radar. Journal of Geophysical Research 113: B11408, DOI 10.1029/2008JB005807.
8.
Figueiredo PM, Hill JS, Merschat AJ, Scheip CM, Stewart KG, Owen LA, Wooten RM, Carter MW, Szymanski E, Horton SP, Wegmann KW, Bohnenstiehl DR, Thompson GW, Witt A, Cattanach B and Douglas T, 2022. The Mw 5.1, 9 August 2020, Sparta earthquake, North Carolina: The first documented seismic surface rupture in the eastern United States. GSA Today (The Geological Society of America) 32(3–4): 4–7, DOI 10.1130/GSATG517A.1.
9.
Fournier M, Jolivet L, Davy P and Thomas J-C, 2004. Backarc extension and collision: an experimental approach to the tectonics of Asia. Geophysical Journal International 157: 871–889, DOI 10.1111/j.1365-246X.2004.02223.x.
10.
Gong Z, Sun J, Zhang Z, Fu B and Jia Y, 2017. Optical dating of an offset river terrace sequence across the Karakax fault and its implication for the late Quaternary left-lateral slip rate. Journal of Asian Earth Sciences 147: 415–423, DOI 10.1016/j.jseaes.2017.07.013.
11.
Gordon FR and Lewis JD, 1980. The Meckering and Calingiri Earthquake October 1968 and March 1970. Geological Survey of Western Australia: Perth, Australia, 1980.
12.
Hall R, 2002. Cenozoic geological and plate tectonic evolution of SE Asia and the SW Pacific: computer based reconstructions, model and animations. Journal of Asian Earth Sciences 20: 353–431. DOI 10.1016/S1367-9120(01)00069-4.
13.
Herbert JW, Cooke ML, Oskin M and Difo O, 2014. How much can off-fault deformation contribute to the slip rate discrepancy within the eastern California shear zone?. Geology 42(1): 71-75, DOI 10.1130/g34738.1.
14.
Huntley DJ and Lamothe M, 2001. Ubiquity of anomalous fading in K-feldspars and the measurement and correction for it in optical dating. Canadian Journal of Earth Sciences 38(7): 1093-1106, DOI 10.1139/e01-013.
15.
Inoue D and Choi W-H, 2006. The activity of the Ulsan Fault System based on marine terrace age study at southeastern part of Korean Peninsula. Central Research Institute of Electric Power Industry (CRIEPI) Report: 1-82p.
16.
Kaneda H, Nakata T, Tsutsumi H, Kondo H, Sugito N, Awata Y, Akhtar SS, Majid A, Khattak W, Awan AA, Yeats RS, Hussain A, Ashraf M, Wesnousky SG and Kausar AB, 2008. Surface rupture of the 2005 Kashmir, Pakistan, earthquake and its active tectonic implications. Bulletin of the Seismological Society of America 98: 521-557, DOI 10.1785/0120070073.
17.
Kars RH, Wallinga J and Cohen KM, 2008. A new approach towards anomalous fading correction for feldspar IRSL dating-tests on samples in field saturation. Radiation Measurements 43(2-6): 786-790, DOI 10.1016/j.radmeas.2008.01.021.
18.
Kee W-S, Kim Y-H, Lee H-J, Choi D-L, Kim B-C, Song K-Y, Koh H-J, Lee SR, Hwang YY, Hwang S-H, Park K-G and Sung N-H, 2009. South Eastern Fault Variable Research and DB Construction. Korea Institute of Geoscience and Mineral Resources (KIGAM): 327p (in Korean).
19.
Kim H, Synn J-H, Park C, Song WK, Park ES, Jung Y-B, Cheon D-S, Bae S, Choi S-O, Chang C and Min K-B, 2021. Korea stress map 2020 using hydraulic fracturing and overcoring data. Tunnel & Underground Space 31(3): 145-166, DOI 10.7474/TUS.2021.31.3.145.
20.
Kim K-H, Ree J-H, Kim Y, Kim S, Kang SY and Seo W, 2018. Assessing whether the 2017 Mw 5.4 Pohang earthquake in South Korea was an induced event. Science 360(6392): 1007-1009, DOI 10.1126/science.aat6081.
21.
Kim M-C, Jung S, Yoon S, Jeong R-Y, Song CW and Son M, 2016. Neotectonic crustal deformation and current stress field in the Korean Peninsula and their tectonic implications: a review. The Journal of the Petrological Society of Korea 25: 169-193, DOI 10.7854/JPSK.2016.25.3.169 (in Korean with English abstract).
22.
Kim Y-S and Sanderson DJ, 2008. Earthquake and fault propagation, displacement and damage zone. In: Structural Geology: New Research: 99-117.
23.
Kim Y-S, Son M, Choi J-H, Choi J-H and Lee H-K, 2022. Research and Development of Active Fault of Korea Peninsula. Ministry of the Interior and Safety (MOIS): 278-288p (in Korean).
24.
Kim Y-S, Son M, Choi J-H, Choi J-H, Seong YB and Lee J, 2020. Processes and challenges for the production of Korean active faults map. Journal of the Geological Society of Korea 56(2): 113-134, DOI 10.14770/jgsk.2020.56.2.113 (in Korean with English abstract).
25.
King TR, Quigley M and Clark D, 2019. Surface-rupturing historical earthquakes in Australia and their environmental effects: New insights from re-analyses of observational data. Geosciences 9: 408, DOI 10.3390/geosciences9100408.
26.
Korea Meteorological Administration (KMA), 2012. Historical earthquake records in Korea (2-1904), Yale Jeongpan: 13p (in Korean).
27.
Korea Meteorological Administration (KMA), 2026. Earthquake catalog of the Korean Peninsula. Available at: https://necis.kma.go.kr (accessed 2026 January 26).
28.
Kuwahara Y, Choi J-H, Cheon Y and Imanishi K, 2021. Dependence of earthquake faulting type on fault strike across the Korean Peninsula: Evidence for weak faults and comparison with the Japanese Archipelago. Tectonophysics 804: 228757, DOI 10.1016/j.tecto.2021.228757.
29.
Kyung JB and Lee K, 2006. Active fault study of the Yangsan fault system and Ulsan fault system, southeastern part of the Korean Peninsula. Journal of the Korean Geophysical Society 9(3): 219–230 (in Korean with English abstract).
30.
Kyung JB, 2007. Paleoseismological characteristics of the Yangsan fault zone and the Ulsan fault zone since the late Quaternary. In: Proceeding of the 5th Symposium on the Geology of Korea, No. 3: Quaternary tectonic movements in southeastern Korea, Korea Institute of Geoscience and Mineral Resources (KIGAM): 105-117p (in Korean).
31.
Liritzis I, Stamoulis K, Papachristodoulou C and Ionnides K, 2013. A re-evaluation of radiation dose-rate conversion factors. Mediterranean Archaeology and Archaeometry 13(3): 1-15.
32.
Liu J, Ren Z, Min W, Ha G and Lei J, 2021. The advance in obtaining fault slip rate of strike-slip fault: A review. Earthquake Research Advances 1: 100032, DOI 10.1016/j.eqrea.2021.100032.
33.
Ma K, Lee C, Tsai Y, Shin T and Mori J, 1999. The Chi-Chi, Taiwan earthquake: large surface displacements on an inland thrust fault. Transactions American Geophysical Union 80: 605–611, DOI 10.1029/99eo00405.
34.
McCalpin JP, 2009. Paleoseismology, Second Edition: 315-379p., DOI 10.1016/S0074-6142(09)95005-7.
35.
Mejdahl V, 1987. Internal radioactivity in quartz and feldspar grains. Ancient TL 5(2): 10-17, DOI 10.26034/la.atl.1987.119.
36.
Meyer B, 1991. Méceanismes des Grands Tremblements de Terre et du Raccourcissement Crustal Oblique au Bord Nord-est du Tibet. Ph.D. dissertation, Paris, Université Paris: 129p.
37.
Molnar P and Tapponnier P, 1978. Active tectonics of Tibet. Journal of Geophysical Research 83: 5361-5375, DOI 10.1029/JB083iB11p05361.
38.
Murray AS and Wintle AG, 2000. Luminescence dating of quartz using an improved single-aliquot regenerative-dose protocol. Radiation Measurements 32: 57-73, DOI 10.1016/S1350-4487(99)00253-x.
39.
Okada A, Takemura K, Watanabe W, Suzuki Y and Kyung J-B, 2001. Trench excavation surveys across the Yangsan and Ulsan active fault systems in the southeastern part of Korea Peninsula. Transactions, Japanese Geomorphological Union 22-3: 287-306 (in Japanese).
40.
Okada A, Takemura K, Watanabe M, Suzuki Y, Kyung J-B, Chae Y-H, Taniguchi K, Ishiyama T, Kawabata D, Kaneda H and Naruse T, 1999. Trench excavation survey across the Ulsan (active) fault at Kalgok-ri, Kyongju City, Southeast of Korea. Journal of Geography 108(3): 276-288 (in Japanese), DOI 10.5026/jgeography.108.276.
41.
Ota Y, Chen C-Y and Lee P-N, 2024. The Chaochou active fault in southern Taiwan: Characteristics and geomorphological significance as a reverse fault. Journal of Structural Geology 185: 105191, DOI 10.1016/j.jsg.2024.105191.
42.
Park JC, Kim W, Chung TW, Baag CE and Ree JH, 2007. Focal mechanism of recent earthquakes in the southern Korean Peninsula. Geophysical Journal International 169: 1103-1114, DOI 10.1111/j.1365-246X.2007.03321.x.
43.
Park J-Y, 2004. The structural characteristics of the Tertiary basin in Gyeongju region, Korea. Unpublished M.S. thesis, Seoul National University: 140p (in Korean with English abstract). https://s-space.snu.ac.kr/hand....
44.
Park Y, Ree J-H and Yoo S-H, 2006. Fault slip analysis of Quaternary faults in southeastern Korea. Gondwana Research 9: 118-125, DOI 10.1016/j.gr.2005.06.007.
45.
Philip H and Meghraoui M, 1983. Structural analysis and interpretation of the surface deformations of the El Asnam earthquake of October 10, 1980. Tectonics 2: 17-49, DOI 10.1029/TC002i001p00017.
46.
Prescott JR and Hutton JT, 1994. Cosmic ray contribution to dose rates for luminescence and ESR dating: Large depths and long-term time variations. Radiation Measurements 23(2/3): 497-500, DOI 10.1016/1350-4487(94)90086-8.
47.
Readhead ML, 2002. Absorbed dose fraction for 87Rb β particles. Ancient TL 20(1): 25-28, DOI 10.26034/la.atl.2002.342.
48.
Resor PG, Cooke ML, Marshall ST and Madden EH, 2018. Influence of fault geometry on the spatial distribution of long-term slip with implications for determining representative fault-slip rates. Bulletin of the Seismological Society of America 108: 1837-1852, DOI 10.1785/0120170332.
49.
Ritz JF, Baize S, Ferry M, Larroque C, Audin L, Delouis B and Mathot E, 2020. Surface rupture and shallow fault reactivation during the 2019 Mw 4.9 Le Teil earthquake, France. Communications Earth & Environment 1:10, DOI 10.1038/s43247-020-0012-z.
50.
Rizza M, Mahan SA, Ritz JF, Nazari H, Hollingsworth J and Salamati R, 2011. Using luminescence dating of coarse matrix material to estimate the slip rate of the Astaneh fault, Iran. Quaternary Geochronology 6: 390-406, DOI 10.1016/j.quageo.2011.03.001.
51.
Rubin CM, 1996. Systematic underestimation of earthquake magnitudes from large intracontinental reverse faults: Historical ruptures break across segment boundaries. Geology 24(11): 989-992, DOI 10.1130/0091-7613(1996)024<0989:SUOEMF>2.3.CO;2.
52.
Schwartz DP and Coppersmith KJ, 1984. Fault behavior and characteristic earthquakes: Examples from the Wasatch and San Andreas fault zones. Journal of Geophysical Research Atmospheres 89: 5681-5698, DOI 10.1029/JB089iB07p05681.
53.
Sibson RH, 1985. A note on fault reactivation. Journal of Structural Geology 7(6): 751-754, DOI 10.1016/0191-8141(85)90150-6.
54.
Soh I, Chang C, Lee J, Hong T-K and Park E-S, 2018. Tectonic stress orientations and magnitudes, and friction of faults, deduced from earthquake focal mechanism inversions over the Korean Peninsula. Geophysical Journal International 213(2): 1360-1373, DOI 10.1093/gji/ggy061.
55.
Song CW, Kim M-C, Lim H and Son M, 2022. Geological structures and extension mode of the southwestern part (Bomun area) of the Miocene Pohang basin, SE Korea. Korean Journal of Mineralogy and Petrology 35(3): 235-258, DOI 10.22807/KJMP.2022.35.3.235.
56.
Suzuki Y, Okada A, Takemura K, Kyung J-B, Kim HY, Hirouchi D, Ito A, Ooishi K, Nakamura Y, Naruse T, Kitagawa H and Watanabe M, 2005. Paleoseismic activity at the northern part of the Ulsan fault zone – Excavation study at Kalgok-ri, Kyongju city, southeast Korea. Active Fault Research 25: 147-152 (in Japanese with English abstract).
57.
Tapponnier P and Molnar P, 1976. Slip-line field theory and large-scale continental tectonics. Nature 264: 319-324, DOI 10.1038/264319a0.
58.
Wallace RE, 1977. Profiles and ages of young fault scarps, north-central Nevada. The Geological Society of America 88(9): 1267-1281, DOI 10.1130/0016-7606(1977)88<1267:PAAOTF>2.0.CO;2.
59.
Wang D, Yin G-M, Wang X-L, Liu C-R, Han F and Du J-H, 2016. OSL dating of the late Quaternary slip rate on the Gyaring Co fault in central Tibet. Geochronometria 43: 162-173, DOI 10.1515/geochr-2015-0040.
60.
Wells D and Coppersmith K, 1994. New empirical relationship among magnitude, rupture length, rupture width, rupture area, and surface displacement. Bulletin of the Seismological Society of America 84: 974-1002, DOI 10.1785/BSSA0840040974.
61.
Woo J-U, Rhie J, Kim S, Kang T-S, Kim K-H and Kim YH, 2019. The 2016 Gyeongju earthquake sequence revisited: aftershock interaction within a complex fault system. Geophysical Journal International 217: 58-74, DOI 10.1093/gji/ggz009.
62.
Zechar JD and Frankel KL, 2009. Incorporating and reporting uncertainties in fault slip rates. Journal of Geophysical Research: Solid Earth 114: B12407, DOI 10.1029/2009JB006325.
63.
Zimmerman DW, 1971. Thermoluminescence dating using fine grains from pottery. Archaeometry 13(1): 29-52, DOI 10.1111/j.1475-4754.1971.tb00028.x.
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