Progressive Regional Metamorphism in Southern New Zealand

1938 ◽  
Vol 75 (4) ◽  
pp. 160-174 ◽  
Author(s):  
F. J. Turner
Keyword(s):  
New Zealand ◽  
Regional Metamorphism ◽  
Parent Rock ◽  
Chemical Compositions ◽  
Low Grade ◽  
Scottish Highlands ◽  
The Past ◽  
Structural Peculiarities ◽  
Chemical Conditions ◽  
Pelitic Rocks

During the past ten years a number of papers dealing with progressive regional metamorphism in the southern portion of New Zealand have been published. In the following pages a brief summary of the assemblages of minerals typical of the various metamorphic zones is given, but the writer's main object is to draw attention to certain mineralogical and structural peculiarities that appear to differ in some degree from what are usually regarded as the normal features of regional metamorphism in such classic areas as the Scottish Highlands and the Caledonian chain of Norway. The possibility that such departures from the normal may in some instances be connected with chemical peculiarities in the parent rock is suggested by such phenomena as the well-known general limitation of chloritoid, staurolite, and low-grade garnets to pelitic rocks of special chemical compositions. Other unusual features, especially when found to recur in widely separated regions, may well be governed by some particular combination of physical rather than chemical conditions.

scholarly journals Shear Strength Characterization of Bauxite Deposits in Kuantan, East Coast Malaysia

2019 ◽  
Vol 8 (3S3) ◽  
pp. 404-407
Keyword(s):  
Shear Strength ◽  
Moisture Content ◽  
East Coast ◽  
Field Performance ◽  
Friction Angle ◽  
Parent Rock ◽  
Index Tests ◽  
Strength Characterization ◽  
The Relationship

Engineering characterization which are useful for "temperate" zone soils usually fail to predict the field performance of bauxitic soils, because the index tests upon which the characterization are based are not always reproducible for bauxitic soils. Fifteen (15) bauxitic soil of undisturbed and disturbed samples from 3 distinct sites in Kuantan, all derived from basalt parent rock but representing various stages of weathering were subjected to engineering and mineralogic tests. Values for cohesion and friction angles are evaluated. Soils from Semambu has the highest moisture content of 33.27%, the cohesion value is however lower compared to Bukit Goh which has moisture content of 21.74%. Study are further done to discover the relationship with cohesion and friction angles. Thus, by measuring the cohesion and friction angle can evaluate the performance of bauxite shear strength.

scholarly journals PESTRÉ SEDIMENTY OTTNANGU V BRNĚ-KOHOUTOVICÍCH

2018 ◽  
Vol 25 (1-2) ◽  
Author(s):  
Pavla Tomanová Petrová ◽  
David Buriánek ◽  
Karel Kirchner ◽  
Oldřich Krejčí ◽  
František Laufek ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Clay Minerals ◽  
Heavy Fraction ◽  
Parent Rock ◽  
Fine Grained ◽  
Sediment Layers

The reddish coloured sediment layers (up to 5 m thick) were found within building pit in the Brno-Kohoutovice on the Libušina třída Avenue (NW part of Brno). These sediments were assigned to the Ottnangian based on characteristic pseudoassociation of microfossils. Smectite or illite/smectite dominates over kaolinite among the clay minerals. Minerals typomorphic for granitoids of the Brno Massif, i.e. epidote, amphibole and altered titanite, absolutely dominate (99 mod. %) within the assemblage of translucent heavy fraction. Minerals like garnet and staurolite which are typical for the Ottnangian sediments in this region, are presented only in accessoric amount. The chemical composition of the studied sediments is located between the chemical composition of granodiorites of the Brno Massif and Neogene clays. Relatively high content of Zr, Hf and HREE, which is interpreted as result of presence of very fine grained zircon in studied sediments, is characteristic. High content of SiO2 and comparatively low contents of Al2O3 and Fe2O3 indicates non-lateritic type of weathering. The chemical composition of studied sediments reflects semiarid to humid paleoclimate that the granitoids of the Brno Massif as parent rock have undergone.

scholarly journals Genesis of soils derived from various types of parent rock in Southwestern Japan

1988 ◽  
Vol 34 (1) ◽  
pp. 17-29 ◽  
Author(s):  
Kenzo Miura ◽  
Shigeru Araki ◽  
Kazutake Kyuma
Keyword(s):  
Parent Rock ◽  
Genesis Of Soils

Chemical and mineralogical transformations accompanying the weathering of basic volcanic rocks from New South Wales

Soil Research ◽  
1964 ◽  
Vol 2 (2) ◽  
pp. 218 ◽  
Author(s):  
DC Craig ◽  
FC Loughnan
Keyword(s):  
New South ◽  
New South Wales ◽  
Volcanic Rocks ◽  
Parent Rock ◽  
Steady Increase ◽  
Near Surface ◽  
South Wales ◽  
Alkaline Earths ◽  
Basic Volcanic ◽  
Mineral Transformations

An investigation has been made of the chemical and mineralogical transformations which have accompanied the weathering of six basic volcanic rocks from eastern New South Wales. Montmorillonite is initially formed from the destruction of the olivine, pyroxene, and plagioclase in the parent rock, but, in the near-surface horizons, this mineral is unstable and may form kaolinite, halloysite, or a poorly crystalline montmorillonite. The alumina content shows a steady increase up the profiles, whereas the alkalis, alkaline earths, and some of the silica have been lost in the ground-waters during the mineral transformations. Marked concentrations of iron and titanium occur at specific levels in some of the weathering profiles and explanations of these phenomena are given.

Mineralogy of parent rock and peaty-podzolic soil of Iremel Ridge, Southern Urals

2017 ◽  
Vol 50 (8) ◽  
pp. 961-970
Author(s):  
R. M. Khalitov ◽  
E. N. Perova ◽  
E. V. Abakumov ◽  
R. R. Suleimanov
Keyword(s):  
Podzolic Soil ◽  
Southern Urals ◽  
Parent Rock

Controls of mylonitic compositional layering during non-cataclastic ductile deformation

1974 ◽  
Vol 111 (2) ◽  
pp. 121-123 ◽  
Author(s):  
R. H. Vernon
Keyword(s):  
Grain Size ◽  
Ductile Deformation ◽  
Parent Rock ◽  
Rock Deformation ◽  
Chemical Segregation

SummaryLenticular compositional layering and/or rodding in blastomylonitic rocks, in the simplest situations, can be controlled by (i) the presence of more than one mineral in the parent rock and (ii) relative large grain-size of the parent rock. Deformation and recrystallization during non-cataclastic ductile deformation can produce compositional layering, without chemical segregation.

Sign in / Sign up

Export Citation Format

Share Document