The Yarlung Zangbo suture zone (YZSZ) in southern Tibet is divided by the Zhongba terrane into two subparallel belts in its western end. The northern belt (NB) is tectonically juxtaposed against an accretionary prism complex and the Gangdese magmatic arc of Eurasia along dextral oblique-slip faults. Peridotite massifs in this belt are intruded by mafic dikes, providing critical geochemical, geochronological, and isotopic information about the melting-melt extraction history of the Tethyan mantle. Peridotites consist of harzburgite and clinopyroxene harzburgite with minor Iherzolite and dunite-chromitite. Dolerite and microgabbro dikes crosscutting these peridotites display U-Pb zircon ages of 128–122 Ma, and show normal mid-oceanic ridge basalt (N-MORB) like rare earth element patterns with negative Nb, Ta, and Ti anomalies, high ε_Nd(t) values (+8.39 to +9.28), and (¹⁴³Nd /¹⁴⁴Nd)_{t = 128 Ma} ratios of 0.51290–0.51295. They display high (⁸⁷Sr/⁸⁶Sr)_t ratios of 0.70433–0.70489, and ²⁰⁶Pb/²⁰⁴Pb of 17.546–17.670, ²⁰⁷Pb/²⁰⁴Pb of 15.432–15.581, and ²⁰⁸Pb/²⁰⁴Pb of 37.724–37.845, suggesting that their N-MORB–like mantle source was modified by island arc melts. Slab rollback–induced extension in an arc-trench system along the Eurasian continental margin led to ∼7%–12% partial melting of subduction-influenced, spinel lherzolite peridotites, producing dike magmas. The NB peridotite massifs and ophiolites thus represent a suprasubduction zone oceanic lithosphere formed in close proximity to the late Mesozoic active continental margin of Eurasia.

Early Cretaceous magmatism suggested to be related with the Kerguelen mantle plume has been reported in both eastern and western Tethyan Himalaya (TH). Coeval magmatism has been recently di...

A novel uniplanar dual‐band printed compound loop antenna for WLAN/WiMAX applications is proposed. The proposed antenna consists of a small inner rectangular ring, an outer rectangular loop with three slits and a parasitic strip on one side of the substrate. Fed by the inner ring and collaborated with double rings and the parasitic strip, three resonant frequencies can be achieved, where the parasitic metallic strip between the rings can not only induce a new middle resonant frequency but also improve the impedance matching at the low‐frequency band greatly. By magnetic‐electrical coupling, dual‐band performance with the lower‐wide band covering 2.37–3.78 GHz and the upper‐frequency band covering 5.15–5.85 GHz can be obtained. It is experimentally demonstrated that the proposed antenna with the performance of broadband (covering 2.4/5 GHz WLAN including 2.4–2.484 GHz, 5.15–5.825 GHz and 3.5/5 GHz WiMAX including 3.4–3.69 GHz, 5.25–5.85 GHz, respectively), good dipole‐like radiation characteristics, stable gain and high‐radiation efficiency, is an excellent candidate for WLAN/WiMAX applications.

Ophiolite-hosted diamond from peridotites and podiform chromitites significantly differs from those of kimberlitic diamond and ultra-high pressure (UHP) metamorphic diamond in terms of occurrence, mineral inclusion, as well as carbon and nitrogen isotopic composition. In this review, we briefly summarize the global distribution of twenty-five diamond-bearing ophiolites in different suture zones and outline the bulk-rock compositions, mineral and particular Re-Os isotopic systematics of these ophiolitic chromitites and host peridotites. These data indicate that the subcontinental lithospheric mantle is likely involved in the formation of podiform chromitite. We also provide an overview of the UHP textures and unusual mineral assemblages, including diamonds, other UHP minerals (e.g., moissanite, coesite) and crustal minerals, which robustly offer evidence of crustal recycling in the deep mantle along the suprasubduction zone (SSZ) and then being transported to shallow mantle depths by asthenospheric mantle upwelling in mid-ocean-ridge and SSZ settings. A systematic comparison between four main genetic models provides insights into our understanding of the origin of ophiolite-hosted diamond and the formation of podiform chromitite. Diamond-bearing peridotites and chromitites in ophiolites are important objects to discover new minerals from the deep earth and provide clues on the chemical composition and the physical condition of the deep mantle.

Ophiolites in the southern belt (SB) occur as much larger peridotite massifs compared with those of the northern belt (NB), sporadically overlain by a thin layer of isotropic gabbro in the ...

The Mengyin diamondiferous kimberlite cluster in Shandong province is one of the three major sources of natural diamond in China, where many brown diamonds are mined, but the genesis of their color is still controversial. In this paper, studies including microscopic examination, optical properties of orthogonal polarization, low temperature photoluminescence spectra, infrared spectra, Raman spectra, ultraviolet-visible absorption spectra, luminescence of cathodoluminescence, and transmission electron microscopy have been carried out on the uncut brown diamonds and their slice samples to constrain on the color genesis of brown diamond from the Mengyin deposit. The results show that the brown color is dominantly caused by plastic deformation, and some samples are also caused by non-deformation-related defects and inclusions.