The Cretaceous and Cenozoic tectonic evolution of Southeast Asia

Abstract

Tectonic reconstructions of Southeast Asia have given rise to numerous controversies that include the accretionary history of Sundaland and the enigmatic tectonic origin of the proto-South China Sea. We assimilate a diversity of geological and geophysical observations into a new regional plate model, coupled to a global model, to address these debates. Our approach takes into account terrane suturing and accretion histories, the location of subducted slabs imaged in mantle tomography in order to constrain the evolution of regional subduction zones, as well as plausible absolute and relative plate velocities and tectonic driving mechanisms. We propose a scenario of rifting from northern Gondwana in the latest Jurassic, driven by northward slab pull from north-dipping subduction of Tethyan crust beneath Eurasia, to detach East Java, Mangkalihat, southeast Borneo and West Sulawesi blocks that collided with a Tethyan intraoceanic subduction zone in the mid-Cretaceous and subsequently accreted to the Sunda margin (i.e., southwest Borneo core) in the Late Cretaceous. In accounting for the evolution of plate boundaries, we propose that the Philippine Sea plate originated on the periphery of Tethyan crust forming this northward conveyor. We implement a revised model for the Tethyan intra-oceanic subduction zones to reconcile convergence rates, changes in volcanism and the obduction of ophiolites. In our model the northward margin of Greater India collides with the Kohistan-Ladakh intra-oceanic arc at ∼ 1000 km beneath northern Borneo and the South China Sea are likely to be remnants of the proto-South China Sea basin.

The Dynamic Topography of Eastern China Since the Latest Jurassic Period

“…The reconstruction by Zahirovic et al () is based on that by Müller, Seton, et al (), with some refinements to the eastern Tethyan domain from 160 Ma to present. In Müller, Seton, et al (), the East Java, West Sulawesi, and eastern Borneo are placed on the New Guinea margin prior to breakup at ~160 Ma, following Zahirovic et al (). However, due to the poor preservation of seafloor spreading histories, Zahirovic et al () proposed an alternative scenario, where East Java, West Sulawesi, and eastern Borneo originate from the Argo Abyssal Plain on the NW Shelf of Australia, which is adopted in Zahirovic et al ().…”

“…In Müller, Seton, et al (), the East Java, West Sulawesi, and eastern Borneo are placed on the New Guinea margin prior to breakup at ~160 Ma, following Zahirovic et al (). However, due to the poor preservation of seafloor spreading histories, Zahirovic et al () proposed an alternative scenario, where East Java, West Sulawesi, and eastern Borneo originate from the Argo Abyssal Plain on the NW Shelf of Australia, which is adopted in Zahirovic et al (). In addition, the Sepik and Philippine Arcs are attached to New Guinea before moving northward in Zahirovic et al (), and the north margin was an active margin character, which is consistent with the age and geochemistry of the Central Ophiolite Belt on New Guinea (Permana, ) and also the magmatic and paleomagnetic history of the Philippine Arc (Balmater et al, ; Deng et al, ).…”

Décollements, Detachments, and Rafts in the Extended Crust of Dangerous Ground, South China Sea: The Role of Inherited Contacts

“…This age range exactly coincides with the peak production of Yenshanian granites in South China (Zhou et al, ), strongly supporting that the area of Dangerous Ground was part of a larger Mesozoic granitoid belt of subduction encompassing the margins of South China and East Vietnam (Taylor & Hayes, ; Lapierre et al, ; see discussion in Breitfeld et al, ; Morley, ; Pubellier & Morley, ). This belt, produced by the northwestward subduction beneath eastern Asia of one of the plates that formed the paleo‐Pacific ocean in Jurassic and Cretaceous (Izanagi plate; e.g., Zahirovic et al, ), was active from Middle Jurassic to late Cretaceous, with a sharp decrease of magmatism after 90 Ma (Zhou et al, ). The exact shape of this Cretaceous subduction/accretionary boundary is speculative, but may have been close to Dangerous Ground based on the abundance of granitic rocks west of it (Li et al, ; Pubellier et al, ; Zhou et al, ).…”

Kinematics of a former oceanic plate of the Neotethys revealed by deformation in the Ulukışla basin (Turkey)

“…From the geological record that remains of the paleogeographic domain covered by the Neotethys ocean, which separated Gondwana‐derived continents from Eurasia, multiple synchronous subduction zones have been interpreted for Cretaceous to Paleogene time [e.g., Dewey and Şengör , ; Şengör and Yılmaz , ; Dixon and Robertson , ; Okay , ; Robertson et al , ; Lefebvre et al , ; Jagoutz et al , ; Menant et al , ]. These subduction zones were generally northward dipping and should have surrounded oceanic lithospheric plates in a fashion reminiscent of today's Philippine Sea [ Seno and Maruyama , ; Hall , ; Gaina and Müller , ; Zahirovic et al , ; Wu et al , ], i.e., oceanic lithosphere forming the overriding plate to one subduction system and the downgoing plate to another [e.g., van Hinsbergen et al , ]. Such complex evolution involved the interaction of several microplates, oceanic basins, and intervening magmatic arcs.…”