Bulk-rock geochemical compositions of hypabyssal kimberlites, emplaced through the Archaean Kaapvaal craton and Proterozoic Namaqua–Natal belt, are used to estimate close-to-primary magma compositions of Group I kimberlites (Mg-number 1⁄4 0 82–0 87; 22–28 wt % MgO; 21–30 wt % SiO2; 10–17 wt % CaO; 0 2–1 7 wt % K2O) and Group II kimberlites (Mgnumber 1⁄4 0 86–0 89; 23–29 wt % MgO; 28–36 wt % SiO...

Abstract The origin of the Eastern Mexican Alkaline Province has been explained by landward arc migration and subsequent asthenospheric upwelling after slab roll-back Farallon Plate. In this work, we present new petrographic, mineral chemical, geochemical, geochronological data Sierra de San Carlos-Cruillas (SSCC), one most important complexes in province. This information, together with publis...

Arctic sea ice variations are sensitive to environmental changes and global changes. Freeboard thickness two important parameters in change research. Satellite altimetry can provide long-time large-scale monitoring. We estimated the freeboard its for period from 2002 2012 Envisat satellite data. To remove geoid undulations, we reprocessed data using a newly developed mean surface (MSS) model, n...

Accurate retrieval of ice surface temperature (IST) over the Arctic ice-water mixture zone (IWMZ) is significantly essential for monitoring change polar sea environment. Previous researchers have focused on evaluating accuracy IST in pack regions, possibly account availability situ measurement data. Few them assessed IWMZ. This study utilized Landsat 8/TIRS and Operation IceBridge observations ...

Abstract Mantle-derived volcanic rocks from the Subbetic hyperextended basin in SE Spain provide new insights into composition and mechanical behavior of mantle during continental rifting. The present study describes a sequential restored cross-section along with geochemical characteristics basaltic interbedded within Mesozoic succession basin. Sedimentary stacking patterns minibasins above mob...

In debates on societal collapse, Iceland occupies a position of precarious survival, defined by not becoming extinct, like Norse Greenland, but having endured, sometimes by the narrowest of margins. Classic decline narratives for late medieval to early modern Iceland stress compounding adversities, where climate, trade, political domination, unsustainable practices, and environmental degradatio...

differentiation The process by which planets and satellites develop layers or zones of different chemical and mineralogical composition. flyby Term used to describe the close approach of a spacecraft to a body, without the spacecraft going into orbit around that body. Galilean satellites The four largest satellites of Jupiter (Io, Europa, Ganymede, Callisto), named after their discoverer Galile...