The geochemistry and mineralogy of sediments provide relevant information for the understanding origin metallogenic mechanism ferromanganese nodules crusts. At present, there are still few studies on sediment Clarion–Clipperton Zone (CCZ) east Pacific, particularly systematic with a longer history/length. Here, bulk clay mineral compositions were analyzed 5.7 m gravity core (GC04) obtained at C...

Melt inclusion and host glass compositions from the eastern end of the Southwest IndianRidge showaprogressive depletion in light rare earth elements (LREE), Na8 and (La/Sm)n, but an increase in Fe8, from the NE (648E) towards the SW (498E).These changes indicate an increase in the degree of mantle melting towards the SWand correlate with a shallowing of the ridge axial depth and increase in cru...

From the novel results of comprehensive geological–hydrobiogeochemical studies conducted on Olkhon Island (Lake Baikal), it follows that phenomenon geophagy among wild and domestic ungulates island is caused by deficiency light subgroup rare earth elements (LREE) in plant food natural waters, while not denying possible role other factors. This reflects low LREE specificity most abundant metamor...

Rare earth elements (REE) speciation in laterites are commonly estimated from sequential extraction procedure (SEP). In this study, the selectivity of a 5-steps SEP protocol was evaluated on individual synthetic Ce-material and applied to well-characterized lateritic profile developing over granite bedrock (Madagascar). The Ce-materials representative laterite minerals: Ce-doped oxyhydroxides k...

Abst rac t -Large parts of the Central Eastern Desert of Egypt consist of Neoproterozoic nappes of ophiolite and island-arc volcanic rocks. Beneath these nappes metamorphic basement domes are exposed in tectonic w indows such as the Meatiq basement. The mineral and whole rock chemistry of amphibol i tes included in the teconical ly lowermost granitoid gneiss, within the metasedimentary cover of...

Clinopyroxene megacrysts occurring in Cenozoic mafic alkaline volcanic rocks from the northern margin of Bohemian Massif (SW Poland, SE Germany) could be subdivided by colour and Mg# (Mg/(Mg + Fe tot )) three groups. Megacryst with highest = 90.0–91.5 (“high Mg#”, HMg#) is transparent strongly Light Rare Earth Element (LREE) depleted contains abundant orthopyroxene lamellae. The clinopyroxene “...

Clay mineral authigenesis at continental margins plays an important role in global marine element cycles. However, despite being increasingly used as tracers for both modern and past oceanographic conditions, the behavior of rare earth elements (REEs) their isotopes during clay still remains poorly known. In this study, we report on a detailed geochemical investigation glauconite from West Afri...

La secuencia de rocas volcánicas y volcano-sedimentarias reportadas en el segmento superior la Formación Bocas, subyacen sedimentos rojos Jordán, está constituida por derrames lavas máficas a intermedias piroclásticas félsicas interestratificadas con lodolitas, areniscas tobáceas. En este trabajo se exponen nuevos datos campo, petrográficos geoquímicos una volcánica máfica volcanoclástica félsi...

We report partial melting of an ultrahigh pressure eclogite in the Mesozoic Sulu orogen, China. Eclogitic migmatite shows successive stages of initial intragranular and grain boundary melt droplets, which grow into a three-dimensional interconnected intergranular network, then segregate and accumulate in pressure shadow areas and then merge to form melt channels and dikes that transport magma t...