Intra-arc deformations with vertical rotation axes: the case of the pre-Middle Miocene terranes of Southwest Japan

Kano, Ken‐ichi; Kosaka, Kazuo; Murata, Akinobu; Yanai, Shuichi

doi:10.1016/0040-1951(90)90077-l

Cited by 51 publications

(22 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the southern Fossa Magna region, the fore-arc sediments of Honshu arc and the sediments deposited on the Izu-Bonin arc are strongly deformed by the collision of the two arcs. The southern ISTL was produced by this collision processes (Kano et al, 1990) and its nature and geometry is very different from the northern one. The northern part of the ISTL has an east-dipping fault plane, yet the southern part shows a west-dipping fault plane.…”

Section: Geological Settingmentioning

confidence: 99%

Seismological and geological characterization of the crust in the southern part of northern Fossa Magna, central Japan

et al. 2014

View full text Add to dashboard Cite

The northern Fossa Magna (NMF) is a Miocene rift basin formed in the final stages of the opening of the Sea of Japan. The northern part of Itoigawa-Shizuoka Tectonic Line (ISTL) bounds the western part of the NMF and forms an active fault system that displays one of the largest slip rates in the Japanese islands. Reflection and refraction/wide-angle reflection profiling and earthquake observations by a dense array were undertaken across the northern part of ISTL in order to delineate structures in the crust, and deep geometry of the active fault systems. The ISTL active fault system at depth (ca. 2 km) shows east-dipping low-angle in Omachi and Matsumoto and is extended beneath the Central Uplift Zone and Komoro basin keeping the same dip-angle down to ca. 15 km. The upper part of the crust beneath the Central Uplift Zone is marked by the high Vp and high resistivity zone. Beneath the folded zone of the NMF, the middle to lower crust shows low Vp, low resistivity and more reflective features. The balanced geologic cross-section based on the reflection profiles suggests that the shortening deformation since the late Neogene was produced by the basin inversion of the Miocene low-angle normal fault.

show abstract

Section: Geological Settingmentioning

confidence: 99%

Seismological and geological characterization of the crust in the southern part of northern Fossa Magna, central Japan

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Mélanges in the Shimanto Belt were mainly believed to be from a sedimentary origin, i.e., olistostrome in early 80's [ Taira et al , 1980; Kumon , 1981; Sakai , 1988]. However, careful studies have revealed that some of them are of tectonic or diapiric origin [ Needham , 1987; Taira et al , 1988; Agar , 1990; Kano et al , 1990; Kimura and Mukai , 1991; Onishi and Kimura , 1995; Lewis and Byrne , 1996; Hashimoto and Kimura , 1999; Ujiie et al , 2000; Onishi et al , 2001]. Systematic deformation fabrics consistent with ancient relative plate motion characterize tectonic mélanges [ Kano et al , 1990; Onishi and Kimura , 1995; Onishi et al , 2001; Lewis and Byrne , 2003].…”

Section: Geological Settingmentioning

confidence: 99%

Mélange and its seismogenic roof décollement: A plate boundary fault rock in the subduction zone—An example from the Shimanto Belt, Japan

et al. 2005

View full text Add to dashboard Cite

The Mugi Mélange located in western Shikoku of the Shimanto Belt shows systematic Y‐P deformation fabrics formed by microshear and pressure solution that penetrate throughout the mélange pile. Magnetic susceptibility ellipsoids obtained from the anisotropy of magnetic susceptibility (AMS) are highly oblate. Maximum and minimum axes of the ellipsoids are consistent with the shear orientation of the mélange and the mean pole of P surfaces, respectively. This agreement suggests that the Mugi Mélange was formed as a result of underthrusting of trench filling sediment. Vitrinite reflectance ranges from 2.52% to 3.08%, which corresponds to a maximum paleotemperature of ∼180–200°C. Pseudotachylyte, evidence of a seismogenic slip, was found in the upper boundary roof fault of the Mugi Mélange. However, there is not a thermal gap between the mélange and the overlying coherent piles, and the temperature from vitrinite reflectance gradually rises downward from the coherent piles to the mélange beyond the boundary fault, which suggests that paleoisotherms parallel the boundary fault orientation. The isotherms in the seismogenic zone are estimated as subparallel to the plate boundary décollement. Therefore the setting of the cataclastic boundary fault, which includes pseudotachylyte, appears to be a major plate boundary thrust or a subhorizontal splay fault. A probable geologic setting that accounts for the Mugi Mélange and the seismogenic roof fault is partitioning of the slip along the plate boundary fault in space and time: interseismic slip in the mélange and seismic slip along the roof fault.

show abstract

“…The Kanto Mountains of the Honshu arc consist of preNeogene accretionary prisms in the outer zone, represented by the Sambagawa metamorphic belt, the Chichibu belt, and the Shimanto belt, which are bound to the west by the Itoigawa-Shizuoka Tectonic Line (ISTL) (Taira et al 1989;Kano et al 1990;Suzuki 2002; Figure 1b). The Sambagawa metamorphic belt consists of high-pressure metamorphic rocks of Cretaceous age.…”

Section: Tectonic Settingmentioning

confidence: 99%

Crustal structure in the northwestern part of the Izu collision zone in central Japan

Arai

Iwasaki

2014

Earth Planet Sp

View full text Add to dashboard Cite

The Izu-Bonin arc (IBA) has been colliding with the Honshu arc since the middle Miocene, which together form the active Izu arc-arc collision zone (ICZ) in central Japan. To understand the entire collisional system, we have used refraction/wide-angle reflection data to model velocity structures of the Honshu arc, northwest of the ICZ. The seismic data indicate that the upper 4-km crust of the Honshu arc consists of a horizontally homogenous layer with P wave velocity (Vp) of 5.6 to 6.0 km/s and S wave velocity (Vs) of 3.4 to 3.7 km/s. This uniformity is in contrast with the heterogeneous structure further south, where the accreted crustal blocks of the IBA are bounded by dipping collisional boundaries. These contrasting structures suggest that crustal shorting caused by the arc-arc collision has been mostly accommodated within the IBA by reverse faulting along collisional boundaries, with the Honshu arc undergoing relatively little crustal deformation. The high-velocity body of the Kofu granitic complex (KGC), generated by partial melting of the subducted IBA crust, is mostly situated at >4-km depths but shallows significantly just beneath the Kofu Basin. This structural change implies that most of the KGC magma had erupted from just beneath the Kofu Basin.

show abstract

Intra-arc deformations with vertical rotation axes: the case of the pre-Middle Miocene terranes of Southwest Japan

Cited by 51 publications

References 31 publications

Seismological and geological characterization of the crust in the southern part of northern Fossa Magna, central Japan

Seismological and geological characterization of the crust in the southern part of northern Fossa Magna, central Japan

Mélange and its seismogenic roof décollement: A plate boundary fault rock in the subduction zone—An example from the Shimanto Belt, Japan

Crustal structure in the northwestern part of the Izu collision zone in central Japan

Contact Info

Product

Resources

About