Virtually all of the economic Ni–Cu–(platinum group element (PGE)) mineralization in the central part of the Cape Smith Belt of New Québec is hosted by thick olivine cumulate units in the Katinniq Member of the Raglan Formation at the base of the 1.9 Ga Chukotat Group. These units transgress underlying gabbros and pelitic metasediments, forming 50–200-m deep and 300– 1,000-m wide V-shaped embay...

In this paper we classify the range of feldspathic igneous rocks using five geochemical variables: the FeO/(FeOþMgO) ratio or Fe-index, the modified alkali^lime index, the aluminum-saturation index, the alkalinity index, and the feldspathoid silica-saturation index.The Fe-index distinguishes between melts that have undergone extensive iron enrichment during differentiation from those that have ...

To explain Venus' young surface age and lack of plate tectonics, tectonic regime has often been proposed to be either an episodic-lid with global lithospheric overturns, or equilibrium resurfacing numerous volcanic activities. Here, we use 2-D thermochemical convection models realistic parameters, including rheology (dislocation creep, diffusion plastic yielding), experiment-based plagioclase (...

Introduction: Traditionally, the diogenite meteorites have been viewed as orthopyroxenite cumulates with small amounts of olivine [1]. Several olivine-rich, harzburgite diogenites have recently been recognized and may provide insight into the occurrence of olivine on Vesta and in the HED meteorite suite [2,3]. In both the harzburgite and orthopyroxenite diogenites, olivine has been interpreted ...

Abstract Peridotite–magma interaction is important in establishing magma pathways through the mantle and metasomatism of lithospheric mantle. Reactions that consume orthopyroxene produce olivine clinopyroxene are particular interest because these reactions should lead to a redistribution trace elements between solid melt phases at equilibrium. This study examines silica-undersaturated alkaline ...

Basaltic rocks exposed in the Shiting to Yinko area in northern Taiwan are considered to represent a member of the products of the Neogene intraplate volcanism in the Fujian-Taiwan region of the SE China continental margin. This paper presents new age dating, petrographic (including mineral chemistry) and geochemical data which suggest the existence of two groups of the basaltic rocks: the earl...

Abstract We conducted the geochemical modeling of trace element contents for primary melts olivine-phyric rocks from Kamchatsky Mys. This reveals substantial chemical heterogeneity their source while average composition is close to enriched DMM (E-DMM). The estimation melting degree in range 9.1 ± 3.8% model modal batch 15.4 5.2% accumulated fractional melting, which slightly higher than primit...

Introduction: Thanks to the instruments onboard recent ground-based and orbital missions, an unprecedented amount of high quality data exists relevant to the secondary minerals characteristics of the altered martian surface. One of the most striking results is that sulfates are among the most abundant secondary phases and are concentrated in geological units intermediate in age between older No...

Introduction: Mars’ basaltic crust has been altered by H2O to form hydrated silicates (mostly clays) that are distributed globally [1,2] and extend to great depth [3]. However, climate models for early Mars are challenged to generate warm and wet environments needed to form these minerals via weathering near or at the surface [4,5], and geomorphic evidence for surface hydrology seems to postdat...

The Tissint meteorite is a geochemically depleted, olivine-phyric shergottite. Olivine megacrysts contain 300–600 lm cores with uniform Mg# (~80 1) followed by concentric zones of Fe-enrichment toward the rims. We applied a number of tests to distinguish the relationship of these megacrysts to the host rock. Major and trace element compositions of the Mg-rich core in olivine are in equilibrium ...