Landslide Zone Investigation by Determining Cracks and Cracks Compressive Strength Test in Waru District, Pamekasan Regency

Landslide zone investigation has been conducted using geoelectricity to determine the number of cracks and using a compressive strength test to determine compressive strength cracks. The result of this research is that the rock layers of Waru District consist of soil layers resulting from the weathering of quartz rock into quartz sandstone. This quartz sandstone lies on top of a more solid rock layer. The type of landslide that is formed in the Waru sub-district is translational. This type of landslide is caused by water entering the lower layer, causing landslides and the number of cracks that trigger landslides. The results of the low compressive strength test resulted in landslides. This result was due to a decrease in the number of pores filled with water and an increase in the pores that were not filled with water. This occurs due to the presence of water in the cracks, the number of cracks cavities, and the density of the cracks which results in reduced adhesion between the cracks holding layers.

Premelting of ice adsorbed on a rock surface

Considering ice-premelting on a quartz rock surface (i.e. silica) we calculate the Lifshitz excess pressures in a four layer system with rock–ice–water–air.

A Correlation Study Between the Concentrations of Gold, Iron and Sulphate in Quartz Rock Samples Obtained from four Different Locations in Sudan

From four different locations in Sudan namely, Aboharaz (Central Sudan), Port – Sudan (Eastern Sudan) , Algaab (Western Sudan) and Ombal (Southern Sudan) three quartz rocks samples from each location were collected; All samples were analyzed to determine the concentration of Gold (Au(III)), Iron (Fe (III) and Sulphate(SO4-2). Atomic absorption spectrometry technique was used to determine the concentrations of Gold and Iron ,while that of Sulphate has been determined by the use of spectrometry technique. All samples showed positive correlation between gold and sulphate concentration except those collected from Port – Sudan, in addition a negative correlation between gold and iron concentration has been observed in all samples.

STRUCTURAL-TECTONIC AND PETROLOGICAL SIGNS OF LATENT PYRITE-POLYMETALLIC MINERALIZATION BOLONSKOGO TYPE (MOUNTAINOUS OSSETIA)

Детальные полевые наблюдения и петрохимические исследования позволили выделить вблизи Бу- ронского колчеданно-полиметаллического месторождения среди глубоко полиметаморфизованных по- род буронской толщи реликтовые эффузивные породы, превращенные во вторичные кварциты (зоны выщелачивания) и сменяющиеся рассланцованными зеленокаменно измененными порфиритоидами, переслаивающимися с обеленными кварцево-серицитовыми и кварцево-хлоритовыми сланцами и гидро- термально измененными кварцитами-фельзитами. В кварцитах, представляющих почти мономинеральную кварцевую породу (содержание кварца в них составляет 75?80 %), удалось выявить реликтовую порфировую структуру – таблитчатые вкрапленники плагиоклаза полностью замещены кварцем, при четком сохранении их первоначальной таблитчатой фор- мы. Также удалось выявить бластопорфировую структуру порфиритоидов с реликтовой микролитовой структурой основной массы. Ниже дается подробная характеристика стратиграфического положения этих древних эффузивных пород в составе буронской толщи, их петрологических и петрохимических особен- ностей. Пространственная связь Буронского колчеданно-полиметаллического месторождения с обеленными кварцево-серицитовыми сланцами, с зонами вторичных кварцитов и зонами рассланцованных зеленока- менно измененных порфиритоидов очевидна, и может служить признаком при поисках и разведке кол- чеданно-полиметаллического оруденения буронского типа и поставить его в один ряд с колчеданными месторождениями восточного склона Урала и северо-западного Кавказа типа Урупа. Detailed field observations and petrochemical studies allowed to identify close Bolonskogo pyrite-polymetallic deposits among deep polymetamorphic rocks boronski strata relic effusive rocks, converted into secondary quartzites (zone of leaching) and changing russiantvonline Greenstone changed porpitidae, whitewashing interstratified with quartz-sericite and quartz-chlorite schists and hydrothermally altered quartzite-felsite. In quartzite, representing a monomineralic quartz rock (silica content is 75?80 %), it was possible to identify relict porphyritic structure – tabular phenocrysts of plagioclase are completely replaced by quartz, with strict preservation of its original tablet form. Also able to identify blastoporphyritic structure porphyrinoids microlites with relict structure of the main mass. Below is a detailed description of the stratigraphic position of these ancient effusive rocks within boronski strata, and petrological and petrochemical peculiarities. Spatial relationship Bolonskogo pyrite-polymetallic deposits with whitewash quartz-sericite schists, with zones of secondary quartzite and Greenstone areas RussianTown modified porphyrinoids obvious, and can serve as a basis in prospecting for pyrite-polymetallic mineralization Bolonskogo type and put it on a par with the pyrite deposits of the Eastern slope of the Urals and North-Western Caucasus the type of Urup.

QUARTZ MEGACRYSTS IN GREECE: MINERALOGY AND ENVIRONMENT OF FORMATION

Quartz megacrysts in Greece are systematically sampled, described and classified with respect to their morphology, solid inclusion mineralogy, and geological conditions of formation. Quartz deposition took place due to reduction in silica solubility in the hydrothermal fluids in favourable geological environments such as: alpine-type fissures close to major detachment faults, skarns and quartz veins crosscutting and generally related to granitoids and, finally, epithermally altered volcanic rocks of Tertiary age. The varieties of coloured crystals (amethyst, smoky quartz, morion, green quartz, rock crystal), the twinning of the crystals, the mineralogy of solid phases included in quartz (rutile, chlorite, sericite, feldspars) as well as the types and forms of the crystals (Tessin habit, Muzo habit, faden quartz, sceptre, window quartz, interrupted crystals, double-terminated crystals, phantom quartz, gwindel quartz, etc.) give important information on the growth mechanisms and the physico-chemical conditions during quartz formation. The quartz crystals found in several localities are gemmy and their potential for use as gemstones should be evaluated.

PETROGRAPHIC VARIETIES OF QUARTZ ROCK FROM THE WĄDROŻE WIELKIE AREA (FORE-SUDETIC BLOCK) IN NEW OUTCROPS

As evidenced by specific structural and textural features, the quartz rock from Wądroże Wielkie is represented by four basic petrographic types: (1) inequicrystalline quartz rock, (2) finely crystalline porous rock with large quartz crystals, (2) vein quartz in macrocrystalline intergrowths, and (4) vein quartz in heterogranular intergrowths. A common feature of all types of quartz rock is a multistage development. It is visible on the growing succeeding quartz generations on the older crystals and their fragments and in the fills of different kinds of fissures by the younger quartz. The metasomatic origin of the quartz rock is manifested in different ways. Small calcite inclusions in the quartz are common, accompanied by fine quartz, sericite and relics of earlier quartz mineralization. The origin of the quartz rock is related to the circulation of hydrothermal solutions and their metasomatic effect on the pre-existing rocks.

Gemstone deposits of Serbia

Gemstone minerals in Serbia have never been regarded as an interesting and significant resource. Nevertheless, more than 150 deposits and occurrences have been recorded and some of them preliminarily explored in the last 50 years. The majority of deposits and occurrences are located within the Serbo-Macedonian metallogenic province and the most significant metallogenic units at the existing level of knowledge are the Fruska Gora ore district, Cer ore district, Sumadija metallogenic zone, Kopaonik metallogenic zone and Lece-Halkidiki metallogenic zone. The most important genetic type of deposits is hydrothermal, particularly in case of serpentinite/peridotite as host/parent rock. Placer deposits are also economically important. The dominant gemstones are silica minerals: chalcedony (Chrysoprase, carnelian, bluish chalcedony etc.), jasper (picture, landscape, red etc.), common opal (dendritic, green, milky white etc.), silica masses (undivided), and quartz (rock crystal, amethyst etc.). Beside silica minerals significant gemstones in Serbia include also beryl (aquamarine), garnet (almandine and pyrope), tourmaline, fluorite, rhodochrosite, carbonate-silica breccia, carbonate-silica onyx, silicified wood, howlite, serpentinite, marble onyx, and kyanite. This paper aims to present an overview of Serbian gemstone deposits and occurrences and their position based on a simplified gemstone metallogenic map of Serbia, as well as genetic-industrial classification of gemstone deposits and gemstone varieties.