Uplift and denudation history of the Akaishi Range, a thrust block formed by arc-arc collision in central Japan: Insights from low-temperature thermochronometry and thermokinematic modeling
S Sueoka, Y Ikeda, K Kano, H Tsutsumi, T Tagami, BP Kohn, N Hasebe, A Tamura, S Arai, K Shibata
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH | AMER GEOPHYSICAL UNION | Published : 2017
Fission track (FT), (U-Th)/He (He), and U-Pb data were used to identify the denudation history of the Akaishi Range, central Japan. The northern Akaishi Range is bounded on the east by the Itoigawa-Shizuoka Tectonic Line Fault Zone (ISTL-FZ). The thermochronometric ages progressively decrease with the decreasing distance to the ISTL-FZ. Thermokinematic calculations suggest that the age pattern observed can be explained by 5–7.5 mm/yr reverse slip on the ISTL-FZ that dips 34–45° west and soles onto detachment at 20–22.5 km depth. By assuming the same geometry and slip rate of the fault, the bedrock uplift rates and denudation rates are estimated at ~4 mm/yr. Thus, the uplift and denudation st..View full abstract
Awarded by Japan Society for the Promotion of Science
Awarded by Grants-in-Aid for Scientific Research
Yoshiki Shirahama of Tokyo University assisted with sampling. Atsumasa Okada of Ritsumeikan University, Keiji Takemura of Kyoto University, and Shinji Toda of Tohoku University provided valuable advices during the study. We thank Hayato Uyeda and an anonymous reviewer for their constructive and valuable comments. This work was partially supported by a Grant-in-Aid for Scientific Research by Japan Society for the Promotion of Science to Hiroyuki Tsutsumi (grant 20650155) and Grant-in-Aid for Research by Tokyo Geographical Society to Shigeru Sueoka (research title: Uplift and denudation history of the Akaishi Range based on low-temperature thermochronometric methods). The University of Melbourne thermochronology laboratory receives infrastructure support under the AuScope Program of NCRIS. The Kanto Regional Environment Office permitted us to collect rock samples in the Minami Alps National Park. Some figures in this paper were drawn by the Generic Mapping Tools (GMT) [Wessel and Smith, 1991] and 30 arc sec grid of General Bathymetric Chart of the Oceans (GEBCO). A more detailed discussion of the methodology can be found in the supporting information [Carlson et al., 1999; Danhara and Iwano, 2013; Evans et al., 2005; Hasebe et al., 2009; Holden and Hoffman, 2000; Orihashi et al., 2008; Pearce et al., 1997; Yoshioka et al., 2005]. The data for this paper are presented in the tables and supporting information.