Triassic sedimentation and postaccretionary crustal evolution along the Solonker suture zone in Inner Mongolia, China
MetadataShow full item record
Copyright © 2014 American Geophysical Union. All Rights Reserved
Detrital zircon U-Pb dating of the Xingfuzhilu Formation in southern Inner Mongolia yields a maximum depositional age of around 220 Ma. The predominantly Permian and Triassic zircons are characterized by oscillatory zoning and euhedral shapes, with mostly positive zircon εHf(t) values (+2.0 to +16.4), indicating that they were derived from a proximal magmatic source. Early-Middle Paleozoic zircons have variable zircon εHf(t) values from −6.2 to +11.2 and are characterized by weak oscillatory zoning and subhedral-subrounded shapes, suggesting that the sources are a proximal magmatic arc, possibly mixed with components of the Ondor Sum magmatic arc and the magmatic arc at the northern margin of the North China Craton. The remnants of Precambrian blocks in the southeastern Central Asian Orogenic Belt (CAOB), and the North China Craton may also have been a minor source region for the Xingfuzhilu succession. These results, combined with regional data, indicate that a closing remnant ocean basin or narrow seaway possibly existed in the Middle Permian (Guadalupian) immediately prior to final collision of the CAOB and closure of the Paleo-Asian Ocean. Subsequent collision resulted in the crustal uplift and thickening along the Solonker suture zone, accompanied by possible slab break-off and lithospheric delamination during the Latest Permian to Middle Triassic. The resultant orogen in the Late Triassic underwent exhumation and denudation of rocks in response to the postorogenic collapse and regional extension. Vertical crustal growth in the Triassic is documented by detrital zircons from the Xingfuzhilu Formation and appears to have been widespread across entire eastern CAOB.
Showing items related by title, author, creator and subject.
The crustal architecture of Myanmar imaged through zircon U-Pb, Lu-Hf and O isotopes: Tectonic and metallogenic implicationsGardiner, Nicholas; Searle, M.; Morley, C.; Robb, L.; Whitehouse, M.; Roberts, N.; Kirkland, Chris; Spencer, Christopher (2018)The Tethys margin in central and eastern Asia is comprised of continental terranes separated by suture zones, some of which remain cryptic. Determining the crustal architecture, and therefore the geological history, of ...
Provenance of Permian-Triassic Gondwana Sequence units accreted to the Banda Arc in the Timor region: Constraints from zircon U-Pb and Hf isotopesSpencer, Christopher; Harris, R.; Major, J. (2015)Analysis of zircons from Australian affinity Permian-Triassic units of the Timor region yield age distributions with large age peaks at 230-400. Ma and 1750-1900. Ma, which are similar to zircon age spectra found in rocks ...
U-Pb age and Hf-O isotopes of detrital zircons from Hainan Island: Implications for Mesozoic subduction modelsJiang, X.; Li, X.; Collins, William; Huang, H. (2015)A compilation of magmatic ages from the Mesozoic South China Block suggests a number of "magmatic quiescence" periods at ca. 205-195 Ma, ca. 150-140 Ma and ca. 125-115 Ma, casting doubt on tectonic models that suggest ...