Remote sensing and geophysical studies for groundwater exploration in Osmania University campus, Hyderabad, India: A case study

With the increasing resolution of satellite sensors, it is possible to fruitfully exploit the special advantages of image analysis for a wide range of geological environments. With this view, a LISS-III and PAN merged image of the 1600 acre (approximately 6.5 sq km) Osmania University (OU) campus taken from IRS-ID in the month of May (a fairly representative month in terms of minimum annual drainage/vegetation cover) was acquired. The image was then digitally processed and visually interpreted for potential groundwater resource regions. Since occurrence of groundwater in crystalline rocks, the host rocks for the entire Hyderabad region, is generally associated with secondary porosity, the accent was on determining and establishing lineaments of considerable surface extent. This was then augmented with maps of subsurface features as obtained from geophysical studies for the southern part of 0 U campus and available bore well/open well information. Subsequently, information from the three sources was integrated for a better understanding of the geological situation and the interrelationship of its various constituents to determine possible locations of groundwater resources. The significant findings comprised the identification of three major dykes, two running E-W and the third running NE-SW. A major N-S linear exposure of granitic rocks, as also several criss-crossing fractures in the southern side of the campus, along with the prevailing drainage pattern for the entire campus area were mapped. Based on these findings and supporting geophysical/hydrogeological data, a geological/lithological map of Osmania University campus was prepared and prospective groundwater zones have been identified.

Mineralogical Characterization of Early Bronze Age Pottery from the Svilengrad-Brantiite Site, Southeastern Bulgaria

Several pottery sherds from the Svilengrad-Brantiite site, Bulgaria, were mineralogically and petrographically analyzed. The aim was to add information to the very scarce material data available for Early Bronze Age pottery in the southeastern Thrace plain, Bulgaria, in order to examine a possible raw-material source of the pottery. The characterization techniques applied were optical microscopy (OM), petrographic microscopy (PM), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDS), X-ray fluorescence (XRF) spectroscopy, and X-ray diffraction (XRD). The pottery samples consisted of two typological groups: a local-made type and a cord-impressed decoration type influenced by foreign cultures. All of the samples were produced from fine clay pastes that had a quite similar composition, with abundant mineral grains of similar mineral composition and fragments of metamorphic and granitic rocks. The chemical compositions of each mineral in the grains and fragments were almost identical, and consistent with those from metamorphic and granitic rocks from the Sakar-Strandja Mountains near the study site. The clay paste compositions corresponded to those of illite/smectite mixed-layer clay minerals or mixtures of illite and smectite, and the clay-mineral species were consistent with those in Miocene–Pleistocene or Holocene sediments surrounding the site.

Supplemental Material: Middle-lower crustal flow in response to the India-Eurasia collision: Structural evidence from the southern Chong Shan belt within the Sundaland block, southeastern Tibetan Plateau

S1: Analytical Methods; Table S1: Summary of Mineral assemblages, microstructures and temperature data; Table S2: Zircon U-Pb LA-ICP-MS data of the granitic rocks from the Chong Shan structural belt.

Supplemental Material: Middle-lower crustal flow in response to the India-Eurasia collision: Structural evidence from the southern Chong Shan belt within the Sundaland block, southeastern Tibetan Plateau

S1: Analytical Methods; Table S1: Summary of Mineral assemblages, microstructures and temperature data; Table S2: Zircon U-Pb LA-ICP-MS data of the granitic rocks from the Chong Shan structural belt.

The spatial association of accessory minerals with biotite in granitic rocks from the South Mountain Batholith, Nova Scotia, Canada

We use mineral liberation analysis (MLA) to quantify the spatial association of 15,118 grains of accessory apatite, monazite, xenotime, and zircon with essential biotite, and clustered with themselves, in a peraluminous biotite granodiorite from the South Mountain Batholith in Nova Scotia (Canada). A random distribution of accessory minerals demands that the proportion of accessory minerals in contact with biotite is identical to the proportion of biotite in the rock, and the binary touching factor (percentage of accessory mineral touching biotite divided by modal proportion of biotite) would be ~1.00. Instead, the mean binary touching factors for the four accessory minerals in relation to biotite are: apatite (5.06 for 11,168 grains), monazite (4.68 for 857 grains), xenotime (4.36 for 217 grains), and zircon (5.05 for 2876 grains). Shared perimeter factors give similar values. Accessory mineral grains that straddle biotite grain boundaries are larger than completely locked, or completely liberated, accessory grains. Only apatite-monazite clusters are significantly more abundant than expected for random distribution. The high, and statistically significant, binary touching factors and shared perimeter factors suggest a strong physical or chemical control on their spatial association. We evaluate random collisions in magma (synneusis), heterogeneous nucleation processes, induced nucleation in passively enriched boundary layers, and induced nucleation in actively enriched boundary layers to explain the significant touching factors. All processes operate during the crystallization history of the magma, but induced nucleation in passively and actively enriched boundary layers are most likely to explain the strong spatial association of phosphate accessories and zircon with biotite. In addition, at least some of the apatite and zircon may also enter the granitic magma as inclusions in grains of Ostwald-ripened xenocrystic biotite.

Fossilization of Precambrian microfossils in the Volyn pegmatite, Ukraine

We report on Precambrian soft-tissue microfossils from igneous rocks of the Volyn pegmatite district, associated with the Paleoproterozoic Korosten Pluton, north-western Ukraine. The fossils were recovered from m-sized miarolitic cavities and show a well-preserved 3D morphology, mostly fibrous, but with a large variety of fiber types, and also in irregular, flaky shapes reminiscent of former biofilms, and rare spherical objects. Based on literature data, own pyrolysis experiments and reflected light microscopy results, the organic matter (OM) is characterized as (oxy)kerite. Further investigations with microscopic techniques, including scanning and transmission electron microscopy, and electron microprobe analysis show that fossilization likely occurred during a hydrothermal, post-pegmatitic event, by silicification dominantly in the outermost 1–2 µm of the microfossils. The hydrothermal fluid, derived from the pegmatitic environment, was enriched in SiF4, Al, Ca, Na, K, Cl, and S. The OM shows O enrichment where N and S content is low, indicating simultaneous N and S loss during anaerobic oxidation. Mineralization with Al-silicates starts at the rim of the microfossils, continues in its outer parts into identifiable encrustations and intergrowths of clay minerals, feldspar, Ca-sulfate, Ca-phosphate, Fe-sulfide, and fluorite. Breccias, formed during collapse of some the miarolitic cavities, contain also decaying OM, which released high concentrations of dissolved NH4+, responsible for the late-stage formation of buddingtonite and tobelite-rich muscovite. The age of the fossils can be restricted to the time between the pegmatite formation, at ~1.760 Ga, and the breccia formation at ~ 1.49 Ga. As geological environment for growth of the microorganisms and fossilization we assume a geyser system, in which the essential biological components C, N, S, and P for growth of the orgabisms n the miarolitic caves were derived from microorganisms at the surface. Fossilization was induced by magmatic SiF4-rich fluids. The Volyn occurrence is a prime example of Precambrian fossils and the results underline the importance of cavities in granitic rocks as a possible habitat for microorganisms of the deep biosphere.

Petrogenesis and Tectonic Setting of Early Cretaceous Intrusive Rocks in the Northern Ulanhot Area, Central and Southern Great Xing’an Range, NE China

Abundant Early Cretaceous magmatism is conserved in the central and southern Great Xing’an Range (GXR) and has significant geodynamic implications for the study of the Late Mesozoic tectonic framework of northeast China. In this study, we provide new high-precision U–Pb zircon geochronology, whole-rock geochemistry, and zircon Hf isotopic data for representative intrusive rocks from the northern part of the Ulanhot area to illustrate the petrogenesis types and magma source of these rocks and evaluate the tectonic setting of the central-southern GXR. Laser ablation inductively coupled plasma–mass spectrometry (LA-ICP-MS) zircon U–Pb dating showed that magmatism in the Ulanhot area (monzonite porphyry: 128.07 ± 0.62 Ma, quartz monzonite porphyry: 127.47 ± 0.36, quartz porphyry: 124.85 ± 0.34, and granite porphyry: 124.15 ± 0.31 Ma) occurred during the Early Cretaceous. Geochemically, monzonite porphyry belongs to the metaluminous and alkaline series rocks and is characterized by high Al2O3 (average 17.74 wt.%) and TiO2 (average 0.88 wt.%) and low Ni (average 4.63 ppm), Cr (average 6.69 ppm), Mg# (average 31.11), Y (average 15.16 ppm), and Yb (average 1.62 ppm) content with enrichment in Ba, K, Pb, Sr, Zr, and Hf and depletion in Ti, Nb, and Ta. The granitic rocks (e.g., quartz monzonite porphyry, quartz porphyry, and granite porphyry) pertain to the category of high-K calc-alkaline rocks and are characterized by high SiO2 content (>66 wt.%) and low MgO (average 0.69 wt.%), Mg# (average 31.49 ppm), Ni (average 2.78 ppm), and Cr (average 8.10 ppm) content, showing an affinity to I-type granite accompanied by Nb, Ta, P, and Ti depletion and negative Eu anomalies (δEu = 0.57–0.96; average 0.82). The Hf isotopic data suggest that these rocks were the product of the partial melting of juvenile crustal rocks. Notably, fractionation crystallization plays a crucial role in the process of magma emplacement. Combining our study with published ones, we proposed that the Early Cretaceous intrusive rocks in the Ulanhot area were formed in an extensional tectonic background and compactly related to the subduction of the Paleo-Pacific Ocean plate.

Cretaceous Granitic Magmatism in South-Central Vietnam: Constraints from Zircon U–Pb Geochronology

South-central Vietnam abundantly presents magmatic rocks with larger volumes ofCretaceous granitic rocks. In this study, zircon U–Pb geochronology of granite samples from the Deoca,Ankroet, and Dinhquan complexes in south-central Vietnam are utilized to investigate Cretaceousgranitic magmatism. According to U–Pb analysis results, zircon ages of granitic rocks display the Deocaat ~113–92 Ma, the Ankroet at ~103–98 Ma, and the Dinhquan at ~97–113 Ma. The range of ages isnarrow from 113 to 92 Ma, with most common ages date at ~100 Ma. Published data and our resultsdisplay that Cretaceous granitic magmatism was active between ~87–118 Ma and most active at ~100Ma in south-central Vietnam. Additionally, the Deoca and Dinhquan complexes show inherited ages inTriassic followed by Proterozoic and Carboniferous to Ordovician. The obtained ages indicate that Itypegranitic rocks could be derived from melting of basement rocks. Our study suggests that I-typegranitic rocks in south-central Vietnam were significantly intruded around 100 Ma.

Architectural Significance of Granite and Other Durable Rocks in the Context of India – An Analytical Study

Architectures created through the cutting of naturally occurred massive rocks include different structures, buildings, tombs, monuments, caves and sculptures. On account of hard and tough property, the granite is considered as strong construction stone in human history. Granite is very common in the continental crust of our mother earth. It is characterised as coarse grained plutonic intrusive igneous rock and is composed of quartz, alkali feldspar and plagioclase. Typical mineralogical character and textural varieties of granite facilitates to develop a wide range of colours, which include white, pink and grey etc. Granite rocks established itself as praiseworthy architecture stone since historical past because of its distinctive character like durability, appreciable finishing, fascinating polish nature and above all its magnificent colour diversities. As architectural stone, the granitic rocks demand attraction owing to the combination of style and elegance. The application of granitic rocks is witnessed in the ancient world through the mesmerising major architectures in India and around the world like Mount Rushmore, Washington Monument, Great Pyramid of Giza; Ajanta and Ellora caves, monolithic structure in the Zagwe-built Lalibela in Ethiopia along with in most of the long-lived old Indian temples, old forts and monuments etc. The monolithic free-standing architecture is generally rock-cut structures as depicted in the Ellora Kailasanathar Temple. The biggest monolithic statue in world, the Gommateshwara statue of Bahubali at Shravanabelagola present in the Indian state at Karnataka was carved in the 983 CE from a single block of granite rock. The radioactivity stuff in the granite is an important concern to the people in recent world. Even though the impact of radioactivity is proved mostly very less harmful to mankind, current research indicates that few granite products are showing radioactive substance index beyond permissible limit of the specified standard, which is responsible for environmental pollution during the use for long. Therefore, due attention is required towards the pertinent issue of radioactivity in the granite stones. Apart from granite, many of the architectures in India are created by the other rock types that include rocks like sedimentary, metamorphic and igneous rocks.