Abstract Most known porphyry Cu deposits formed in the Phanerozoic and are exclusively associated with moderately oxidized, sulfur-rich, hydrous arc-related magmas derived from partial melting of asthenospheric mantle metasomatized by slab-derived fluids. Yet, whether similar metallogenic processes also operated Precambrian remains obscure. Here we address issue investigating origin, f O 2 , S ...

Abstract Subduction of oceanic lithosphere is a diagnostic characteristic plate tectonics. However, the geodynamic processes from initiation to termination subduction zones remain enigmatic mainly due scarcity appropriate rock records. We report first discovery early Paleozoic boninitic blueschists and associated greenschists eastern Proto-Tethyan North Qilian orogenic belt, northeastern Tibet,...

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...

RapidArc radiotherapy technology from Varian Medical Systems is one of the most complex delivery systems currently available, and achieves an entire intensity-modulated radiation therapy (IMRT) treatment in a single gantry rotation about the patient. Three dynamic parameters can be continuously varied to create IMRT dose distributions-the speed of rotation, beam shaping aperture and delivery do...

New Zealand’s newest and most active volcano, Mt. Ngauruhoe in the Taupo Volcanic Zone, produced andesite fl ows in 1949 and 1954, and avalanche deposits in 1975. Potassium-argon “dating” of fi ve of these fl ows and deposits yielded K-Ar model “ages” from <0.27 Ma to 3.5±0.2 Ma. “Dates” could not be reproduced, even from splits of the same samples from the same fl ow, the explanation being var...

The pedicled pectoralis major myocutaneous (PMMC) flap is versatile, and is widely used for the treatment of surgical defects following oral cancer resection. Although free-tissue transfer of a vascularized free flap is often preferred, the clinical benefits of the PMMC flap should not be overlooked. The conventional technique of harvesting a PMMC flap involves a single vascular supply from the...

-The Mesozoic to Eocene sedimentary succession of Hazara Basin dominated by carbonates is characterized by a distinct package of sediments punctuated by a number of diastems, hiatus and unconformities. The Hazara Basin evolved in Hettangian with the development of lagoonal to upper shoreface conditions on the northern margin of northward flying India. It was followed by a thick pile of middle J...

Tephra preserved in sediments form useful isochronous marker layers, linking disparate geological, palaeoenvironmental and archaeological records. The application of tephrochronology is greatly enhanced through the detection macroscopically invisible tephra (cryptotephra). Here, we identify two discrete cryptotephra Samoan lake sediments, first identification region outside New Zealand. Geochem...

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...