Very large volume (>1000 km of magma) crystal-rich dacitic ignimbrites that lack pronounced evidence of fractional crystallization or vertical zonation erupt in some continental magmatic arcs (e.g. the Lund Tuff of the Great Basin and the Fish Canyon Tuff of Colorado in western USA). Apparently, their magma chambers were only modestly heterogeneous and not systematically zoned from top to botto...

The problem of crystal sizes is one of the central problems of differentiation of a terrestrial magma ocean and it has been an arbitrary parameter in previous models. The crystal sizes are controlled by kinetics of nucleation and crystal growth in a convective magma ocean. In contrast with crystallization in magma chambers, volcanic lavas, dikes, and other relatively well studied systems, nucle...

We explore the potential effects of magmatic assimilation on mineral growth and mineral zoning in an alkali olivine basaltic magma using both equilibrium thermodynamics and kinetics. The equilibrium-model calculations simulate fractional crystallization alone (closed system) and coupled assimilation fractional crystallization (AFC) (open system); the models predict the assemblages ofmagmatig mi...

In the process of desulfurization, will produce a lot of the desulfurization liquid, desulphurization waste liquid containing high concentrations of salt, has the very good use value. If direct emissions will not only damage to the environment, but also wastes resources The reduction of the pollution resulting from desulfurization was studied. Rotary evaporator was employed to simulate vacuum c...

The Precambrian Dullstroom Formation of South Africa, which is predominantly composed of basaltic andesites interbedded with subordinate sedimentary and felsic volcanic strata, represents the ®rst phase of an extended period of magmatism that was responsible for the Bushveld Magmatic Province, including the extrusive Rooiberg Group and the intrusive Bushveld Complex. New geochemical and isotopi...

[1] Analysis of the compositions of crystals and melt inclusions from a suite of 40 gabbroic and wehrlitic nodules in a single eruptive body provides a record of concurrent mixing and crystallization of melts under NE Iceland. The crystals in the nodules have a similar range of compositions to those found as phenocrysts in the flow, and many of the nodules may have been generated by crystalliza...

EVALUATION OF A FRACTIONAL CRYSTALLIZATION MODEL and AN EXPERIMENTAL STUDY OF THE PARTITIONING OF A RARE EARTH ELEMENT IN THE SYSTEM DIOPSIDE/WATER by ROBERT A. ZIELINSKI B.A. RUTGERS UNIVERSITY (1967) SUBMITTED TO THE DEPARTMENT OF EARTH AND PLANETARY SCIENCES IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY Septembe...

The installation of heat pumps in different chemical processes is considered as an important and prospective approach for energy saving. Various crystallization processes such as counter current crystallization, direct and indirect contact crystallization, evaporative crystallization and fractional crystallization from melts are used to be a promising chemical processes where heat pumps can be ...

Geochemical, isotopic and age constraints support a comagmatic origin for Ghuweir Mafics and the Feinan A-type granites. The two rocks types, named collectively in this paper as the Feinan Ghuweir Magmatic Suite (FGMS), formed between 556 and 572Ma ago according to Rb–Sr whole-rock dating. FGMS has low Sr initial ratios, which preclude a significant contribution of much older crust in the magma...

Recent physical theories for the formation of the Earth suggest that about 4.5 b.y. ago the mantle of the Earth was partially or completely molten. Fractional crystallization of this hypothetical magma ocean would result in a strong chemical stratification of the Earth's mantle. Such a scenario is controversial from the geochemical point of view. However, it has been noted that the simple scena...