Short episodes of crust generation during protracted accretionary processes: Evidence from Central Asian Orogenic Belt, NW China
Journal
Geodynamics and Tectonophysics
Journal Volume
8
Journal Issue
3
Pages
573-574
Date Issued
2017
Author(s)
Abstract
continental crust but the spatial and temporal distribution of crust generation within individual orogens remains poorly constrained. Paleozoic (~540–270 Ma) granitic rocks from the Alati, Junggar and Chinese Tianshan segments of the Central Asian Orogenic Belt (CAOB) have markedly bimodal age frequency distributions with peaks of ages at ~400 Ma and 280 Ma for the Altai segment, and ~430 Ma and 300 Ma for the Junggar and Chinese Tianshan segments. Most of the magma was generated in short time intervals (~20–40 Ma), and variations in magma volumes and in Nd–Hf isotope ratios are taken to reflect variable rates of new crust generation within a long-lived convergent plate setting.
SDGs
Type
conference paper