Active continental subduction and crustal exhumation: the Taiwan orogeny

Abstract

A tectonic model of active continental subduction followed by crustal exhumation is proposed to explain the orogeny in Taiwan. The subducted crust is represented by a low‐velocity zone dipping eastwards beneath the major part of Taiwan, while the exhumed crust is marked by a high‐velocity bulge, high heat flow and absence of seismicity beneath the eastern Central Range. The boundary between the subducted and exhumed crust has been identified from surface geology and analyses of thermal history across the Central Range. The dynamic force that has been driving the exhumed crust is identified by results from focal mechanisms, structural geology and geodetic survey in the eastern Central Range. Such a tectonic model may provide a good explanation for the evolution of the Taiwan Orogeny, as well as an active case for studying other long‐extinct systems of continental subduction and exhumation.

Tectono-metamorphic history of the ophiolitic Lento unit (northern Corsica): evidences for the complexity of accretion-exhumation processes in a fossil subduction system

“…In this picture, only the last D4 phase show structural features referable to extensional tectonics. The complexity of the exhumation path, as also reconstructed for the Lento unit, is also reported by studies about others fossil accretionary wedges, where different processes, as, for instance, a combinations of upward extrusion, extension and erosion [85,10,86,87,88] have been identified during the exhumation.…”

The Volcanic Earthquake Swarm of October 20, 2009 in the Tatun Area of Northern Taiwan

“…This occurrence provided good opportunity to study the tectonic activity beneath the Tatun volcanic area. Although those earthquakes were not very large (M L = 2.8 to 3.2) compared with significant seismicity in other parts of Taiwan where a convergent plate boundary is located (Lin 2002), most of the residents in the Taipei metropolitan area felt strong ground motion due to short epicenter distances as well as extremely shallow hypocenters. The residents in the Tatun volcanic area felt particularly strong shaking.…”

Seismic Stratigraphic Features of the Late Miocene-Present Unconformities and Related Seismic Units, Northern Offshore Taiwan

“…The central part of the Taiwan, which is characterized by high mountain peaks of Taiwan mountain ranges, is bearing the culmination of the collisional activity (Figure 1b) [22,23]. Accordingly, the northward descending topography of the mountain range represents the northward decline of the collision [6].…”