It has been observed that anisotropic nature of rocks is assumed to be caused by disparity in their petrography (mineralogy, texture and micro-structures) including physical properties. These variations have been revealed to occur even in locations where there are only a few centimetres apart on most outcrops. Furthermore, comparable rock types in most localities may not yield the same engineer...

A sequence of sixteen photomicrographs of thin sections of unaltered quartz diorite through a zone of deformation to myrmekite-bearing granite near Temecula, California, shows the textural and mineralogical changes that occurred in a quartz diorite as (1) K-metasomatism altered the primary plagioclase crystals to form microcline, myrmekite, quartz-bleb clusters, and recrystallized sodic plagioc...

Mafic rocks including basalts and gabbros are the main constituents of Birjand ophiolites. They are found in several places and show low grade metamorphism in the field and under the microscope. Chondrite-normalized REE patterns for basalts and gabbros indicate that these rocks are transitional-enriched to depleted mid-oceanic ridge basalts respectively. Otherwise, N-MORB normalized trace eleme...

Zircon grains were separated from lunar regolith and rocks returned from four Apollo landing sites, and analyzed in situ by secondary ion mass spectrometry. Many regolith zircons preserve magmatic dO and trace element compositions and, although out of petrologic context, represent a relatively unexplored resource for study of the Moon and possibly other bodies in the solar system. The combinati...

The Wooley Creek batholith and Slinkard pluton are adjacent plutons with identical U-Pb zircon ages of 161 +4/-2 Ma. The plutons dip toward each other, which suggests that they are connected in the subsurface. Geologic and thermochemical evidence shows that the Slinkard pluton is the structurally lowest part of the system and the Wooley Creek batholith the structurally highest, with a total str...

Xenoliths of metamorphic country rocks are locally abundant within breccia sequences in gabbroic to troctolitic rocks of the Voisey's Bay Intrusion, Labrador, Canada. Thermochemical interaction with mafic magma has produced restite assemblages in the xenoliths that are composed of Ca-rich plagioclase, corundum, hercynite and minor magnetite. Hercynite was produced as a result of the breakdown o...

The Glória quartz-monzodiorite, one of the mafic plutons of the Paleoproterozoic Mineiro belt, is intrusive into banded gneisses, amphibolites, schists and phyllites of the Rio das Mortes greenstone belt, in the southern portion of the São Francisco Craton, State of Minas Gerais, Brazil. The Glória quartz-monzodiorite yields a SHRIMP U-Pb zircon age of 2188 +/- 29 Ma, suggesting a tectonic rela...

The volcanic Rooiberg Group represents the earliest phase of Bushveld-related magmatism and comprises, in some areas, the floor and roof rocks of the mafic–ultramafic intrusive units of the Bushveld Complex. The lower to middle Dullstroom Formation is composed of two interbedded series of low Ti and high Ti volcanic strata, which are predominantly basaltic andesites. Volcanic units above these ...