Compositional fields for spinels from a wide variety of mafic– a wide range of conditions from mafic and ultramafic ultramafic igneous rock types and tectonic environments have been magmas and, in the case of chromites, are often among determined from a global database of over 26 000 analyses. the first phases to crystallize. They also exhibit a wide These fields are defined using contoured dat...

Abstract Reconstructing the tectonic architecture of southern Altaids is great importance to piece together continental growth history Central Asian continent. In this paper, we address subduction‐accretion process Paleo‐Tianshan Ocean, one branch South Tianshan in Altaids, through a detailed geological and geochemical investigation Wulanmoren Accretionary Complex (WAC). The WAC composed ophiol...

The Tethyan Himalaya is the fourth metallogenic belt discovered to date within Tibetan Plateau and contains chromite, gold Sb–polymetallic mineralization. records a series of complex tectonic–magmatic events that include break-up, subduction, collision, detachment, obduction Eastern Gondwana continent, all which generated ideal conditions for ore formation. However, this area remains under-expl...

baft ophiolitic – mélange belt is a part of the ophiolite melange belt of central iran whose genesis is considered as an environment related to tethys subduction at upper cretaceous. major part of intrusive masses of baft ophiolitic – melange form gabbros with the inequigranular texture fine to coarse and pegmatitic, plagiogranites also with inequigranular general texture have been developed wi...

ASTER (Advanced Spaceborne Thermal Emission and Reflection) satellite imagery is useful in assisting lithologic mapping and, however, its effectiveness is yet to be evaluated for lithologic complex such as tectonic mélange. The Mugagangri Group (MG), the signature unit of the Bangong-Nujiang suture zone (BNSZ), Tibet and consisting of ophiolitic mélanges, was previously mapped as a single unit ...

chaldoran area in nw of iran has mesozoic oceanic crust basement. the studied rocks of this region can be divided into three groups: ophiolitic gabbros and pillow lavas, ophiolitic volcanoclastics and eocene lava flows. ophiolitic mafic rocks show continental volcanic arc natures and eocene lava flow shows oib-like nature. during the mesozoic,the chaldoran region was situated in the active cont...