Geology, Geomorphology and Tectonics of India: Introduction

The earth crustal growth since its formation still need in depth research is the conclusion of the three International Conferences on Precambrian Continental Growth and Tectonism, in 2005, 2009 and 2013, organised at the Institute of Earth Sciences of Bundelkhand University, Jhansi, India and its proceedings have valuable source for advance research published the great ideas and achievements from scientists (Chandra et al. 2007; Singh and Chandra, 2011 and Singh et al., 2015). Therefore, this thematic issue planned for consider of crustal growth and tectonic evolution of Indian shield which include 7 research articles on geodynamic evolution of earth, geomorphology, structural, petrologic, isotopic, tectonic, and geochemistry investigations related to the Indian shield and its economic importance (Figure 1)

New observations of Tin Mineralization Potential Vis-à-Vis Ore Petrographic, Alteration and Geochemistry in the Southeastern part of Bastar Craton, Central India

The Tin mineralizations occur around the Katekalyan area, hosted in the acid magmatic rocks. The evolution differentiating granitic magma shows residual melt enrichment where end products intruded as pegmatites into the rocks. The different kind of pegmatite occur as simple unzoned, recrystallized (granitic pegmatite), and metasomatic greisenised and albitised pegmatites which emplaced within the pre-existing rocks of metabasic intrusive, granite (KG), granite gneiss (KGG). Sometimes it also found in metasediments as mineralised and non-mineralised characters along the fractures and foliation planes trending N-S, E-W and more frequently are observed NNW-SSE trends. Cassiterite is most important Tin-ore mineral and associated with pegmatites. Some cassiterite samples exhibit colourless to brown shades zoning which indicate multi stage growth. The cassiterite samples contain significant amounts of Sn, Nb, Ta with minor W. The partial melting model shows that the variation 5 to 50% partial melting of bulk continental crust for KG as well as KGG rocks but bulk distribution coefficient for Sr (DSr) shows low i.e. <<10. The upper limit of partial melting of bulk crust estimates ~50 % for KG and KGG rocks are consistent with required rheological, critical melt percentage to leave the source region has decreased granite melt which were capable to mineralised tin ore elements. It is interesting to note that the SnF4 and SnCl4 probably not stable in presence of water under geologically reasonable conditions

Geochemistry and tectonic setting of the supracrustal rocks from the central part of the Bundelkhand craton, India

Supracrustal rocks (mafics and ultramafics) occurs along with banded iron formation, and felsic volcanics around Babina, Dhaura, and Mauranipur linear east-west trends in central part of the Bundelkhand craton represent Archean crust. The mafic and ultramafic rocks geochemically classified into Komatiite and Basaltic Komatiite and have high-Fe Tholeiitic in composition which may relate with the primitive mantle. The major and trace element geochemistry of mafic and ultramafic rocks correspond to hydrated mantle with wedge tectonic sources and ocean ridge geological characteristics

Studies on enantioselective allylic oxidation of olefins using peresters catalyzed by Cu(I)-complexes of chiral pybox ligands

Enantioselective allylic oxidation of olefins with various peresters, using a catalytic amount of Cu(I)-pybox complex, can be tuned to achieve high asymmetric induction (up to 98% ee) by choosing a unique combination of a ligand and a perester at room temperature. The asymmetric induction in the reaction strongly depends on the nature of the substituents attached to the aryl ring of peresters. The presence of a gem-diphenyl group at C-5 and secondary or tertiary alkyl substituents at the chiral center (C-4) of the oxazoline rings is crucial for high enantioselectivity. A π–π stacking model has been proposed and discussed to explain the stereochemical outcome of the reaction

Neoarchean crustal shear zones and implications of shear indicators in tectonic evolution of Bundelkhand craton, central India

The gneisses and granitoids emplaced along E-W sub-vertical crustal shear zones are represented as important tectonic units in Bundelkhand craton of central India. The tonalite-trondhjemite-granodiorite (TTG) gneisses (3.5-3.2 Ga; oldest unit), and streaky to mafic gneisses structurally deformed in D 1 deformation. The metabasic, felsic, banded iron formation and metasedimentaries of greenstone complex exposed in central part, have characteristics of three sets of folding (F 1 -F 3 ). These gneisses associated with migmatite, amphibolite, quartzite, and schist were evolved in D 2 compressive phase, which are not occurring in northern part of craton. The K-rich Neoarchean granitoids (2.6-2.49 Ga) were intruded as granitic complex (D 3 magmatic phase) and the E-W strike-slip Raksa-Garhmau shear zone reported as important tectonic unit, were evolved in asyn-to post-tectonic D 3 phase. The dolerite dykes (ca. 2.0 Ga) were emplaced along NW-SE fractures in extension setting during D 4 magmatic event. The NE-SW riedel shears occupied by giant quartz veins (reefs) evolved in Paleoproterozoic during D 5 endogenic activity. The relationship between macro and microstructural fabrics has been documented within mylonitic foliation, stretching lineation, S-C planes and rotated fabrics, reflect mesoscopic shear indicators, as noted in three types of mylonitic rocks. i) The rotated porphyroclasts of quartz, feldspars and asymmetric pressure shadows showing strong undulose extinction, deformation lamellae, and dynamic recrystallization are characteristic features of protomylonite where altered orthoclase and kinked plagioclase are noticed. ii) Mylonite, a distinct mylonitic foliation represented by parallel orientation of elongated quartz and feldspar with flakes of mica. iii) The ground matrix of recrystallized quartz with few protoliths of quartz and feldspar are observed, important features of ultramylonite. The asymmetric microstructures viz. σa and σb mantled porphyroclasts, othermicrostructures show progressively deformed by crystal plastic (non-coaxial) strain softening under low to moderate temperature conditions. The sinistral top- to- SW sense of shear movement was dominant. The microfractures/ microfaults, kinking and pull apart structures observed in K- feldspars and are indicative of overprinting of brittle deformation on ductile shearing

Institutionalizing community led action for sanitary survey

Bacteriological contamination in drinking water is the major source for child mortality. Developing countries are facing problem of cholera, dysentery, diahorrea, typhoid and jaundice. Therefore prevention of bacteriological contamination is necessary for sustainability. In Uttar Pradesh, there are large number of people suffer from water related diseases as they draw unsafe water from private shallow hand pumps and dug wells, which is a major cause of avoidable morbidity and mortality. The only viable option today is developing a process of water quality surveillance, through which people can develop the necessary knowledge and skills to monitor the quality of water they consume, undertake corrective measures and sustain the same on their own. Under National Rural Drinking Water Quality Monitoring and Surveillance Programme, Mr. V.K. Mishra and Mr. Arvind Kr. Singh has developed the Community Led Action for Sanitary Survey (CLASS) is an IEC tool to facilitate community to undertake sanitary survey, water quality bacteriological testing and analysis of all drinking water sources in the village and develop collecting action for remedial measures

Rapid action towards ODF in Saharanpur District in India: stunting, menstruation and other innovations in CLTS

In 2016, the Ministry of Drinking Water and Sanitation(MDWS), Government of India (GoI) empanelled competent organizations and individuals to offer on-demand capacity building support and guidance on community wide approaches for sanitation to different districts and states in India. The Water Supply & Sanitation Collaborative Council (WSSCC) is an UN agency and as an empanelled organization for training works closely with the district of Saharanpur towards making it an ODF district. Constantly looking for innovative ways to influence behaviour change, WSSCC deployed new tools of stunting and menstruation to galvanize communities to make Saharanpur an open defecation free district of Uttar Pradesh. It showed startling success in the district within few months without using cash incentive to propel behaviour change. This paper outlines the new methods and tools adopted for community wide approaches, its challenges and outcomes