The major characteristics of ridge subduction in the Central Asian Orogenic Belt and their research advances
Ridge subduction occurs when an expanding mid-ocean ridge intersects a subduction zone and descends into the mantle along with a subducting oceanic plate.This is a significant and widespread geological process within modern oceanic plate dynamics.Due to their distinct structural and morphological characteristics,mid-ocean ridges play a crucial role in influencing subduction angles,the thermal structure of subduction zones,island arc magmatism,continental crust growth,and metal mineralization,which have garnered considerable attention.When a mid-ocean ridge subducts,it creates a slab window,leading to the formation of a unique set of rocks such as adakites,high-magnesium andesites,and Nb-enriched basalts,which are closely associated with copper and gold mineralization.This paper reviews the history and current state of research on geological processes related to modern ridge subduction and explores the associated tectonic movements,magmatic activity,and mineralization patterns.Most of the above features have been described and analyzed in many parts of the Central Asian Orogenic Belt(CAOB),particularly in West Junggar,Altai,East Junggar,Beishan,Chinese Tianshan,Inner Mongolia,Alxa,and Khanka.By examining the spatiotemporal distribution of ridge subduction in the CAOB,this study revealed that the related magmatic activities primarily occurred along the southern margin of the CAOB during two main periods:490-371 Ma and 338-254 Ma.It is proposed that there were at least two major mid-ocean ridge subduction events during these intervals.Moreover,many mineral deposits in the CAOB,especially in northern Xinjiang,are believed to have formed as a result of ridge subduction,indicating that this process may have played a crucial role in the mineralization of the region.Therefore,the identification of ridge subduction in the CAOB is crucial for revealing the complex lateral and vertical accretionary processes of the continental crust and has significant implications for understanding metallogenic activities.
ridge subductionslab windowsCentral Asian Orogenic Beltcontinental crust accretionmineralization
万方数据
维普
