Mafic

Cda.rhona.tedBeverages. Tartaric acid has been used like citric acid as an acidulant in carbonated beverages (qv). However, it has almost been completely replaced in the marketplace by less expensive acidulants like phosphoric, citric, mafic, and fumaric acids. 

Distinctions between glauconite and celadonite may be vague in the area of approximately 0.2% tetrahedral Al. Celadonite is found as an alteration mineral in mafic volcanic rocks (127). 

Most copper deposits are (/) porphyry deposits and vein replacement deposits, (2) strata-bound deposits in sedimentary rocks, (J) massive sulfide deposits in volcanic rocks, (4) magmatic segregates associated with nickel in mafic intmsives, or (5) native copper, typified by the lava-associated deposits of the Keweenaw Peninsula, Michigan. 

Feux, A. N. and Baker, D. R. (1973). Stable carbon isotopes in selected granitic, mafic, and ultramafic igneous rocks. Geochim. Cosmochim. Acta 37, 2509-2521. 

Blundy JD, Brooker RA (2003) Trace element partitioning during melting and ciystalhzation of mafic rocks in the lower crust. Contrib Mineral Petrol (submitted). 

Michael PJ (1988) Partition coefficients for rare earth elements in mafic minerals of high silica rhyohtes the importance of accessory mineral inclusions. Geochim Cosmochim Acta 52 275-282 Mysen BO (1979) Nickel partitioning between olivine and silicate melt Henry s Law revisited. Am Mineral 64 1107-1114... 

Clipperton and Orozco Transforms (10-12°N EPR) (Fig. 2D). These authors analyzed samples known to be derived from a heterogeneous source based on their Sr/ Sr signatures and found a strong relationship between ( Th)/( Th) and Th (and U) concentrations of their samples. This study was the first to suggest that small-scale mafic heterogeneities in the mantle source control much of the U-series systematics of MORE. 

Reagan MK, Sims KW, Erich J, Thomas RB, Cheng H, Edwards RL, Layne G, Ball L (2003) Timescales of differentiation from mafic parents to rhyolite in North American continental arcs. J Petrol (in press) Regelous M, Collerson KD, Ewart A, Wendt JI (1997) Trace element transport rates in subduction zones evidence from Th, Sr and Pb isotope data for Tonga-Kermadec arc lavas. Earth Planet Sci Lett 150 291-302... 

Valuable mineral deposits which form by residual concentration pertain to iron, manganese, aluminum, nickel, clays, tin and gold. Aluminum comes almost exclusively from residual concentrations of bauxite, which result from the laterihsation of alumina rich igneous rocks like syenites under tropical and subtropical climatic conditions. Laterites also contribute nearly 80% of the world s reserves of nickel at grades better than 1% Ni. They form by residual concentrations as a result of weathering of mafic and ultramafic igneous rocks, which are relatively enriched in nickel. 

Crocket, J. H., Platinum-Group Elements in Mafic and Ultra-... 

The Archaean Yilgarn Craton is composed mainly of granite, with mafic, volcanic and sedimentary greenstone rocks. It is one of the world s principal mineral provinces, with considerable resources of primary and supergene Au, sulfide-hosted and lateritic nickel, bauxite, as well as a wide range of other commodities. 

Figure 5 presents Ni in 0-5-cm soils. There are no notable elevated concentrations of Ni in the region, with the exception of northern Maine and north-central New Brunswick. Figure 6 displays Ni in the C-horizon where there is a distinctive elevated Ni signature spatially correlative with the mafic rocks of northern New Brunswick that host mineralization at the Bathurst mining camp. 

Detectior limits Acidic rock Inter- mediate rook Basic rook Ultra- mafic rook Sand- stone Shale Carbo- nate Gneiss Leptite Amphi- bolite Meta- pelite Vlarble Alluvial plain soils Soils Stream Sedi- ments Shallo w sea Sed- iments... 

Acidic rock Inter- mediat e rock Basic rock Ultra- mafic rock Sand- stone Shale Carbo nate Gneis s Leptit e Amphi bolite Meta- pelite Marbl e Alluvia I plain soil Soil Stream sedimen t shallow sea edimen t... 

Bulk rock geochemistry of the Lac Cinquante deposit shows that the Archean volcanic rocks (both the mafic volcanic flows and the bimodal volcanic suite) are dominantly tholeiitic high-Fe basalts and basaltic andesites. The alternating felsic units in the bimodal suite are dacitic and rhyolitic in composition (Fig. 2). 

ABSTRACT A geochemical analysis of major, trace and rare earth elements was carried out in beach sands collected from the Northeastern coast of Mexico in order to observe the spatial trends along three different beaches. Results show that major elements patterns along the beaches are controlled by heavy minerals and plutonic and sedimentary input towards the coast. In addition, trace elements tendencies indicate that the beach sands are influenced by the presence of magnetite. Finally, the differences in Eu anomalies indicate a mix of felsic to mafic and intermediate rocks and feldspar weathering. 

Rare earth elements patterns show differences in Eu anomalies for the samples studied from Boca del Tordo (Fig. 5) that can be attributed to the mix of felsic and mafic sources. This variation can also be explained due to the impoverishment of feldspars due to weathering (Kasper-Zubillaga etal. 2008b). Also Boca del... 

Rare earth elements trends show a negative and positive Eu anomalies in some samples studied from the Northeastern beaches suggesting a mix of felsic and mafic source rocks and feldspar weathering. 

The Expo Intrusive Suite is for the most part composed of mafic and ultramafic intrusions, shaped as tabular-shaped discordant bodies, so are referred as dykes. The Expo suite is economically important due to the presence of sulfide mineralization in the internal part of the intrusion. It is composed of gabbro norite, pyroxenite, peridotite, and dunite. 

The geology of Cyprus is dominated by four distinct terranes - the Troodos Ophiolite Complex composed of mafic and ultramafic rocks, the Circum-Troodos Sedimentary Sequence containing calcarenites, siltstones and carbonates, the Mamonia Complex composed of igneous, sedimentary and metamorphic rocks and the Kyrenia Terrain containing a series of allochthonous massive and recrystallised limestones dolomites and marbles. These terranes generate highly varied landscapes (Fig 1). 

The Stillwater Complex consists of a sequence of differential layers of mafic and ultramafic rocks, which extend for a strike length of up to 40 km and has a maximum exposed thickness of about 7.4 m [3], There are several mineralization zones at the Stillwater Complex, including a PGM-rich zone and a low-grade zone. The Stillwater ore that is processed nowadays contains olivine, plagioclase, as well as plagioclase-brauzite, all of which are naturally hydrophobic gangue minerals. 

The mg is a useful parameter in petrologic problems it varies rapidly with the fractionation of mafic minerals from basalts and is left almost unchanged by assimilation of crustal material, which contains very little Fe and Mg. The two coordinates may be considered as ratios, CaO with a constant denominator, mg with (Fe + Mg) as the denominator. Mixing and fractionation relationships are therefore not straight lines in such a diagram. The mixing curvature is usually strong as it is a function of the atomic (Fe + Mg) contents in crust and basalt, which are usually extremely different. <>... 

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