Granites

This article deals with some geochemical parameters of some selected chemical data of the younger granite of Egypt. The younger granites have a composition ranging from Alkali feldspar granite to syenogranites. the major oxides (FeO, CaO, MgO, Al2O3, MnO, Na2O) show symmetrical variation which indicated continuous variation and fractional crystallization from the pure magmatic melt. It was concluded that these rocks exhibit alkaline affinity and fractional crystallization from the magmatic melt. This younger granites are classified according to their geological setting and petrography to belong to Phase III which is mainly alkali granites. The younger granite of Egypt seems to be homogeneous chemically and mineralogically, unfoliated, hard resist weathering to a great extent. The relations between Al2O3 and SiO2 indicate that most investigated samples are post-orogenic granite(POG). These results are also confirmed by using the relation between (FeOt/FeOt+MgO) and SiO2 wt%.

Field evidence from Upper Palaeozoic and Mesozoic strata exposed in Peninsular Malaysia demonstrates that the structural style, degree and orientation of folding, axial-plane cleavage , and faulting in the Triassic, Jurassic and Cretaceous rocks of the central basin are remarkably similar. In contrast, the Upper Palaeozoic strata, especially the Carboniferous rocks exposed in the eastern part of the peninsula, show multiple phase folding and regional metamorphism unlike anything seen in the Mesozoic rocks . These observations demonstrate that two important compressional events affected Peninsular Malaysia , one in Late Permian times and the other in the mid- to late Cretaceous. The Late Palaeozoic compressional event was a major orogenic mountain building phase with associated emplacement of major Permo- Triassic granite plutons that form the eastern and main ranges . No indications were found of the widely reported Triassic orogenic compression. The palaeotectonic and palaeogeographical implications of these discoveries are important for interpreting the evolution of eastern Gondwana and Tethys. The Raub-Bentong line was an important fault zone active during the Mesozo ic but does not appear to have been a major tectonic suture since the Late Palaeozoic . We postulate that the Permo-Triassic granites of the eastern belt and those presently exposed in the main range were originally about 30-50 km apart, and that Triassic and Jurassic crustal attenuation and subsidence led to the separation of these two granitic belts by more than 100 km.

A research which demonstrates an inexpensive method to estimate uniaxial compressive strength (UCS) value from non-destructive ultrasonic testing for Malaysian granites. UCS value influenced structure’s stability such as cut slopes and excavation of opening in rock mass. Empirical correlation was established for prediction of UCS values from slowness (1/Vp) for dry Malaysian granites.Eliminate the need to conduct expensive, time-consuming and tedious UCS test.

Tin-tungsten-associated granites occur widely in the Dawei region of the Southeast Asian tin belt. In this contribution, we present a detailed study of zircon U–Pb geochronology and whole-rock and zircon elemental
geochemistry for the Wagone and Hermyingyi granites in southern Myanmar, with the aim of determining their
petrogenesis, mineralization associations, and tectonic setting. These granitic rocks, which belong to the high-K
calc-alkaline series A2-type granites, are characterized by high concentrations of SiO2 (75.2–82.5%), Rb
(264–927 ppm), Th (18.4–58.3 ppm), U (10.4–18.3 ppm), and Y (33.5–212 ppm), but low contents of TFeO
(0.57–3.45%), CaO (0.23–0.86%), MgO (0.02–0.19%), MnO (0.01–0.38%), TiO2 (0.01–0.10%), P2O5
(0.003–0.012%), Ba (3–162 ppm), and Sr (4.3–34.4 ppm). Hydrothermal zircons from the mineralized Wagone pluton show an anomalous lack of zoning and vermicular, spongy internal structures, and they contain high concentrations of Ti, Y, U, and light REEs but low Th/U ratios (mostly < 0.1). These features suggest slow
crystallization from a U-enriched and Th-depleted residual magmatic fluid under relatively cool and reducing
conditions. LA-ICPMS U–Pb dating of magmatic and hydrothermal zircons from the two granites yielded concordant ages of 61–60 Ma, indicating an Early Paleogene magmatic-mineralization event. Geochemical and geochronological data suggest that these A-type granites have a crustal origin and were produced by partial melting of a felsic clay-rich source in a back-arc extensional setting. The magmas may have ascended relatively slowly in the crust and experienced crystal fractionation and upper crustal contamination, contributing to intensive Sn–W mineralization in the Dawei area.

In the Castelo Branco region (Central Portugal) mainly occur granitic rocks included in a large pluton composed by two-mica granites and porphyritic two-mica granodiorites and granites; the two-mica granites occupy the nucleus of the pluton and the porphyritic facies are disposed concentrically around them. The indoor radon concentration was measured in 152 dwellings corresponding to three urban areas of the Castelo Branco pluton; one of them is located in the center of the pluton (Alcains) while the other two are located in the western and southern borders (S.Vicente da Beira and Castelo Branco, respectively). The two last ones have dwellings on bedrock of granitic nature and also of contact metamorphosed metasediments of Precambrian to Silurian age. The measured radon concentrations range between 32 and 1055 Bq.m-3, with a median of 110 Bq.m-3. These concentrations are lower than those obtained in other urban areas of Central Portugal (Beiras region) with granitic bedrock. The reason for this difference seems to be related to the lower uranium content of the granites of the studied area, which ranges, on average, from 5 to 7 ppm; the thorium content is also low and averages between 6 and 12 ppm. As a consequence, the absorbed dose is low, ranging between 0,12 to 0,17 μGy/h, and the effective dose, calculated for the population of the studied areas, is 2,9 mSv/year, slightly higher than the national average.

A study is conducted to assess the groundwater quality of the Chhindwara block, Distt. Chhindwara. Specifically, the irrigation water quality is to be determined. The parameters for determining the irrigation water quality are soluble sodium percentage, sodium absorption ratio, Kelley’s ratio, Permeability index, magnesium ratio and residual sodium carbonate. The calculated sodium absorption values of the groundwater samples of the study area suggested that the water is excellent for irrigation purpose. The other parameters also suggest that the groundwater is suitable for irrigation. The samples plotted on U.S. salinity diagram indicate that the groundwater of the region is medium to high saline and low alkaline in nature.

Fluoride content in water has received a world-wide attention due to its importance to health. This study attempts
to trace the factors responsible for low fluoride levels in the aquifers of the Jos Younger Granites despite the high fluorine
content in the rocks. A total of 41groundwater samples (1 mining pond, 2 hand pumps and 38 hand dug wells), 7 rock samples
from the various lithological units, and 13 soil sections from two exposed locations were collected and analyzed for their
fluorine content. Analysis of major cations was carried out using ICP-OES; the anions were analyzed using the UV multi-ion
parameter and bicarbonates by titration method. Fluoride in underground water was determined by multi-ion parameter.
Fluorine in rocks and soil were analyzed by the fusion method. The rock samples show variations in their fluorine content (Jos
– Bukuru Biotite Granite 6,231, aplo-pegmatic granite-gneiss (basement rock) 4,864, Quartz-pyroxenes-fayalite porphyry
1,280, Dilimi-Biotite Granite 258 and Ngeil Biotite Granite-162 ppm). The soil sections from different locations also show
variations of fluorine with depth of sampling. Cumulatively, the fluorine content in the sections and fluoride content in water
do not correlate with fluorine in rock in the rock units. The low content in the two media, indicate that: 1. bulk fluorine have
not been released from minerals in the host rocks and those retained in soils have not been mobilized to the groundwater. 2.
Fluorine have formed complexes with other ions and occurring in compound form rather than ionic form. Apart from low
fluoride in about 70% of the water samples all other parameters are within the WHO recommended limit for house hold uses.
Although there are no records on the effect of low consumption of fluoride in water, inferences from the data show that most
areas with low fluoride level should have dental caries.

The study presents a complex characteristic of zircon from the Verkhneurmiysky intrusive series with Li-F granites. A wide range of morphological and chemical properties of zircon allowed us to obtain new information on the formation and alteration of zircon from biotite and zinnwaldite granitoids and to determine its features, which contribute to the correct definition of Li-F granites formed directly before the tin mineralization. The reviled trends of zircon morphology and composition evolution in the Verkhneurmiysky granites series are: the high-temperature morphotypes are followed by low-temperature ones with more complicated internal structure with secondary alteration zones, mineral inclusions, pores, and cracks; the increasing concentration of volatile (H2O, F), large ion lithophile (Cs, Sr), high field strength (Hf, Nb) and rare-earth elements with decreasing crystallization temperatures and the determining role of the fluid phase (predominantly, F) in the trace element accumulation. The composition of zircon cores in biotite and zinnwaldite granites is very similar. However, the zircon rims from zinnwaldite granites are much more enriched in trace elements compared to those from biotite granites. The first study of zircon from the Verkhneurmiysky granitoids provides new data on the formation and alteration conditions of granitoids, including zinnwaldite ones

Spolia - marbles, granites and other building materials quarried in antiquity and salvaged or wrenched from ancient structures for use in new ones - were commonly used in Roman building during the middle ages, when the city - unlike many regions of Italy - was singularly poor in hard and colorful stones suitable for monolithic columns, revetments and other special uses.  Medieval uses have been well documented and interpreted.  Spolia continued to be used during the Renaissance to an extent that is rarely acknowledged.  This essay examines the subtle but significant changes in how spolia were placed in new buildings in Rome from Bramante to Bernini.  These two architects and their contemporaries shared an apparent desire to elide the difference between the ancient stone and its new setting, whereas architects in the intervening period - among them Vignola,  Ammanati and Maderno - tended to "present" the ancient marble or granite as an object to on display, identifiably of alien origin.  Once the supplies of spolia were depleted in the 17th century, the demands of taste made market conditions propitious for the importing of colored stones from other parts of Italy.

Abstract Tin-tungsten-associated granites occur widely in the Dawei region of the Southeast Asian tin belt. In this contribution, we present a detailed study of zircon U–Pb geochronology and whole-rock and zircon elemental geochemistry for the Wagone and Hermyingyi granites in southern Myanmar, with the aim of determining their petrogenesis, mineralization associations, and tectonic setting. These granitic rocks, which belong to the high-K calc-alkaline series A 2 -type granites, are characterized by high concentrations of SiO 2 (75.2–82.5%), Rb (264–927 ppm), Th (18.4–58.3 ppm), U (10.4–18.3 ppm), and Y (33.5–212 ppm), but low contents of TFeO (0.57–3.45%), CaO (0.23–0.86%), MgO (0.02–0.19%), MnO (0.01–0.38%), TiO 2 (0.01–0.10%), P 2 O 5 (0.003–0.012%), Ba (3–162 ppm), and Sr (4.3–34.4 ppm). Hydrothermal zircons from the mineralized Wagone pluton show an anomalous lack of zoning and vermicular, spongy internal structures, and they contain high concentrations of Ti, Y, U, and light REEs but low Th/U ratios (mostly