Postdoctor JIAO Shujuan and her teacher GUO Jinghui focus on the second garnetite type, from the Xiaoshizi area (Jining terrane of the Khondalite Belt), and utilize its mineral assemblages and microtextures to deduce the P-T evolution.   

The detailed petrography, reaction analyses and independent geothermometric estimates are presented, and a P-T path is derived using a combination of all of these constraints. The metamorphic evolution and petrogeesis of the garneties, an d the implications for the tectonic evolution of Khondalite Belt between the Yinshan and Ordos Blocks, are discussed in the light of this new evidence.     

Fig. 1. (a) Plane-polarized light photomicrograph showing the mineral distribution in the garnetite (DSZ20). (b) A summary sketch showing the distribution of minerals in the garnetite. (Image by JIAO)  

Fig. 2. P-T projection showing the P-T path determined in this study for garnetite and previous metamorphic P-T paths depicted by other researchers. (Image by JIAO)   

Jiao et al. New Constraints from Garnetite on the P-T Path of the Khondalite Belt: Implications for the Tectonic Evolution of the North China Craton. Journal of Petrology, 2013, 54: 1725-1758 （Download Here）