Mafic Ultramafic Intrusions In Beishan And Eastern Tianshan At Southern Caob Petrogenesis Mineralization And Tectonic Implication

The widespread mafic-ultramafic complexes in the Earth are well-known as their hosting Ni-Cu-PGE ore deposits, and their petrogenesis and mineralization have become hot issues in the geological studies. This thesis comprehensively investigated the petrology, mineralogy, geochemistry and geochronology of several mafic-ultramafic complexes in the Beishan Terrane, southern Central Asian Orogenic Belt aimed at systematically determining the mineralization and petrogenetic processes responsible for the formation of the complexes and placing constraints on the tectonic evolution of the Eastern Tianshan and Beishan, and the Early Permian mantle plume. The thesis identified mineralizing indicators of Ni-Cu sulfide deposits and defined the roles of partial melting, fractional crystallization, crustal assimilation and magma injection. The systematical isotopic compositions revealed the mantle source of the mafic-ultramafic complexes had undergone the subduction-related modifications both from the South Tianshan Ocean and subsequently the Junggar Ocean, and that the complexes were emplaced in the period of 269-285 Ma coeval with the 280 Ma mantle plume event in the Tarim Craton. The results of this thesis provide new insights about the tectonic setting, magma evolution, ore genesis, and exploration implications of the mafic-ultramafic complexes in Central Asian Orogenic Belt. Dr. Benxun Su works at the Institute of Geology and Geophysics, Chinese Academy of Sciences, China.

Examines practical and theoretical aspects of the techniques of electron-probe microanalysis, providing material both for practical microanalysts interested in problems and procedures and for researchers who require greater understanding of the principles and developments in correction models.

Continuing the tradition of International Dyke Conference, this book is largely based on contributions from the IDC7 but also includes some chapters by invitation. It focuses on mafic dyke swarms and related associations: e.g. links with sills, kimberlites, syenites, carbonatites, and volcanics, discussing the following themes: (i) regional maps/reviews of dyke swarms and related units, (ii) the role of giant dyke swarms in the reconstruction of supercontinents/paleocontinents, (iii) mapping of dykes using remote sensing techniques, (iv) geochronology of dyke swarms, (v) petrology, geochemistry and petrogenesis of dykes, (vi) emplacement mechanism of dykes, (vii) dyke swarms and planetary bodies, and (viii) links to mineralization and resources.

This volume brings together a collection of papers that summarize current ideas and recent progress in the study of granite-related mineralization systems. They provide a combination of field, experimental and theoretical studies. Papers are grouped according to the main granite-related ore systems: granite-pegmatite, skarn and greisen-veins, porphyry, orogenic gold, intrusion-related, epithermal and porphyry-related gold and base metal, iron oxide-copper-gold (IOCG), and special case studies. The studies provide a broad spread in terms of both space and time, highlighting granite-related ore deposits from Europe (Russia, Sweden, Croatia and Turkey), the Middle East (Iran), Asia (Japan and China) and South America (Brazil and Argentina) and spanning rocks from Palaeoproterozoic to Miocene in age.

Processes and Ore Deposits of Ultramafic-Mafic Magmas through Space and Time focuses on the fundamental processes that control the formation of ore deposits from ultramafic-mafic magmas, covering chromite, platinum-group element (PGE), Ni-sulfides and Ti-V-bearing magnetite. The exploration, exploitation and use of these magmatic ores are important aspects of geology and directly linked to the global economy. Magmatic ores form from ultramafic-mafic magmas and crystallize at high-temperature after emplacement into crustal magma chambers, and are genetically linked to the evolution of the parental magmas through space and time. This book features recent developments in the field of magmatic ore deposits, and is an essential resource for both industry professionals and those in academia. Elucidates the relationships between tectonic settings and magmatic ore mineralization Provides the links between magma generation in the mantle and ore mineralization at crustal levels Features the latest research on changing patterns in magmatic ore mineralization through time and their bearing on the chemical evolution of the Earth’s mantle