Introduction —Convergent plate margin processes and their rock record—


Convergent plate margins are key features of our dynamic planet, and the processes taking place along such margins have had a correspondingly large impact on society and the geologic record. As with many aspects of the geosciences, new insights into the workings of present-day convergent margins facilitate analysis of the rock record of such processes, and the rock record helps us understand active processes at depths below the present level of observation, brought to the surface by erosion and exhumation. The 23 papers in this special issue present research on a variety of localities around the world and span a wide range of geoscience research disciplines, including structural and sedimentary geology, metamorphic petrology, igneous petrology and geochemistry, geochronology, and seismology. The sparks for this volume were four closely related, internationally themed technical sessions held at the Geological Society of America Cordilleran Section Annual Meeting in Fresno, California, in May 2013. Papers related to presentations given in those sessions form the nucleus of the special issue, but this issue includes additional contributions not associated with those technical sessions. Another purpose of this special issue is to honour W. Gary Ernst (Figure 2) for his many years of service as Editor of International Geology Review, as well as for his seminal contributions to our understanding of convergent plate margin processes and their rock record. Under Gary’s leadership from 1995 to 2013, International Geology Review was transformed from an obscure publication of mostly translations of Soviet geoscience into a premier and truly international geoscience journal. Organization of a volume such as this is not an easy matter, because all of the papers are process-oriented in some way in addition to being connected to localities. In this volume we have chosen to group some papers by region and others by subject. We have nine papers that highlight aspects of California–Arizona geology (or Franciscan Complex and related rocks). Five of the Franciscan Complex papers focus on mélanges, so it would have been equally appropriate to group them with the five papers we have grouped within the mélange theme. The five papers representing the mélange theme include one on global localities, one from coastal Chile, two on parts of the Alpine orogen, and one on part of the Variscan orogen. Our other subject-oriented group comprises two papers on mantle fabrics. There are two more broad regional groupings of three papers in the greater Central America–Caribbean area and five papers covering Eurasia and the West Pacific.

International Geology Review, v. 57, no. 5-8, p. v-ix, doi:10.1080/00206814.2015.1026415