SHRIMP U-Pb zircon geochronology of the Huai'an Complex: Constraints on Late Archean to Paleoproterozoic magmatic and metamorphic events in the Trans-North China Orogen

Clicks: 1
ID: 292743
2008
Free PDF
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This article has not been analysed, so there is no overall score — reader engagement is measured and shown alongside.
AI Quality Assessment
Not analyzed
Readership in this journal

Ranked #6,497 of 8,486 articles by views in american journal of science

Most read Least read

Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 8,486 in total.

Mint this article as an NFT
Not yet minted

Create a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.

5 SUSD one-off · no wallet required
Sign in to mint
Abstract
The Huai9an Complex is situated in the northern segment of the Trans-North China Orogen (TNCO), a continent-continent collisional belt along which the discrete Archean Eastern and Western Blocks amalgamated to form the basement of the North China Craton. The complex consists of six distinct lithologic units: the Huai9an TTG gneisses, the Manjinggou high-pressure mafic granulites, the Khondalite Series, the Dongjiagou granitic gneiss, the Huai9an charnockite, and the Dapinggou K-feldspar granite. SHRIMP U--Pb geochronology, combined with Th and U data and cathodoluminescence (CL) imaging of zircons, enables resolution of magmatic and metamorphic events that can be directed towards understanding the late Archean to Paleoproterozoic history of the TNCO. CL images reveal the coexistence of magmatic and metamorphic zircons in most lithologies of the Huai9an Complex, of which the metamorphic zircons occur as either single grains or overgrowth rims surrounding and truncating oscillatory-zoned magmatic zircon cores. SHRIMP U--Pb analyses on magmatic zircons reveal that the tonalitic, trondhjemitic and granodioritic protoliths of the Huai9an TTG gneisses were emplaced at 2515 ± 20 Ma, 2499 ± 19 Ma and 2440 ± 26 Ma, respectively, much earlier than the emplacement of the Dongjiagou granitic gneiss dated at 2036 ± 16 Ma. However, their metamorphic zircons yield similar concordant ^207^Pb/^206^Pb ages of 1847 ± 17 Ma, 1842 ± 10 Ma and 1847 ± 11 Ma for the tonalitic, trondhjemitic and granodioritic gneisses, respectively, and 1839 ± 46 Ma for the Dongjia granitic gneiss. These ages demonstrate that the Huai9an Complex underwent a regional metamorphic event at ∼1850 Ma, which is further supported by a mean ^207^Pb/^206^Pb age of 1848 ± 19 Ma for metamorphic zircons in the Manjinggou high-pressure mafic granulite and 1849 ± 10 Ma and 1850 ± 17 Ma for igneous zircons in the anatectic Huai9an charnockite and Dapinggou garnet-bearing S-type granite, respectively. The timing of late Archean to Paleoproterozoic magmatism and regional metamorphism in the Huai9an Complex is in general agreement with recent SHRIMP zircon data for other metamorphic complexes in the TNCO. These data prove that the high-grade gneiss complexes were not the basement to the low-grade granite-greenstone terranes in the TNCO. Furthermore, the lithologies of the orogen are considered to have developed as a long-lived magmatic arc that was subsequently tectonically disrupted and juxtaposed during the collision of the Eastern and Western Blocks at ∼1.85 Ga, leading to final assembly of the North China Craton.
Reference Key
openalex_W2133316685 Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors Guochun Zhao, Simon A. Wilde, Min Sun, J. Guo, Alfred Kröner, Shoujie Li, Zhang Li, Jian Zhang
Journal american journal of science
Year 2008
DOI
10.2475/03.2008.04
URL
https://ajs.scholasticahq.com/article/61748.pdf
Keywords Keywords not found

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

Comments

No comments yet. Be the first to comment on this article.