HP–UHP metamorphism and tectonic evolution of orogenic belts: introduction

Lifei Zhang,Chunjing Wei,Zeming Zhang,Hans-Peter Schertl

doi:10.1144/sp474.15

Abstract

AbstractHigh pressure (HP) and ultrahigh pressure (UHP) metamorphic rocks play a key role for understanding the tectonic evolution of orogenic belts (Johnson, M.R.W. & Harley, S.L. 2012. Orogenesis: The Making of Mountains. Cambridge University Press, Cambridge). They have typically experienced complex changes during subduction and exhumation processes, arising from recrystallization, deformation, element redistribution, fluid–rock interactions and even partial melting, and may therefore carry a valuable record of evolving geodynamic systems in an orogenic belt. Until now, more than 20 UHP metamorphic belts, i.e. belts which contain rocks that experienced pressure–temperature (P–T) conditions exceeding the lower limit of the coesite stability field, have been identified all over the world (Carswell, D.A. & Compagnoni, R. 2003. Ultrahigh Pressure Metamorphism. Eotvos University Press, European Mineralogical Union, Notes in Mineralogy, Budapest; Liou, J.G., Ernst, W.G., Zhang, R.Y., Tsujimori, T. & Jahn, B.M. 2009. Ultrahigh-pressure minerals and metamorphic terranes – the view from China. Journal of Asian Earth Sciences,35, 199–231; Zheng, Y.F., Zhang, L.F., McClelland, W.C. & Cuthbert, S. 2012. Processes in continental collision zones: preface. Lithos, 136, 1–9). New and innovative studies from different geoscience disciplines have been invaluable in developing a better understanding of the geodynamic evolution of orogenic belts. This special issue contains 15 papers, most of which were presented as part of the session ‘HP–UHP metamorphism and tectonic evolution of orogenic belts’, held at the 35th International Geological Congress in Cape Town, South Africa during 27 August to 4 September, 2016.

Highlights

This special publication comprises of three parts: (I) new developments in the determination of metamorphic P–T conditions and their timing; (II) overview papers of well-known HP–UHP metamorphic belts; and (III) research papers for some newly discovered and/or less well understood HP–UHP belts
The second paper focuses on mineralogical phase relations in metamorphic rocks, which is key to deciphering the metamorphic development during the tectonic evolution of an orogenic belt
Types, with apparent geothermal gradients at >110, 110–55, 55–28 and

Summary

Introduction

This special publication comprises of three parts: (I) new developments in the determination of metamorphic P–T conditions and their timing; (II) overview papers of well-known HP–UHP metamorphic belts; and (III) research papers for some newly discovered and/or less well understood HP–UHP belts. The second paper focuses on mineralogical phase relations in metamorphic rocks, which is key to deciphering the metamorphic development during the tectonic evolution of an orogenic belt.

Results

Conclusion