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M. N. Viswanathiah ¹, M. J. Chandrasekhara Gowda ¹

Affiliations
1 Department of Geology, University of Mysore, Manasa Gangotri, Mysore, IN

Abstract

Occurrence of stromatolitic colonies has been observed in variegated limestones around Alagundi, and they are termed as 'algal stromatolites'. Depending upon the morphological similarities, four different forms have been recognised and their salient features described. Natural environmental factors that prevailed during their formation have been enumerated, and diminution of algal filaments into fine micrite is also discussed.

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M. N. Viswanathiah ¹, V. Venkatachalapathy ¹, A. P. Mahalakshmamma ¹

Affiliations
1 Department of Geology, University of Mysore, Manasa Gangotri, Mysore, IN

Abstract

Studies of several clastic and non-clastic sedimentary samples collected from the' Kaladgi basin have yielded 19 species classifiable into 15 genera, besides a few organic plates: Microtaennia sp., Menneria roblotae, Costatosphaerina angustata, Concentrites muricatus, Protoleiosphaeridium problematicum, Spumiosa alara, Leiosphaeridia aglutinata, L. dhakshinii, L. insigna, Protoleiosphaeridium sp., Granomarginata sp., Vavosphaeridium reticulatum, Trachysphaeridium sp. Leiovalia oblonga, Schismatosphaeridium sp. The results of investigation of these Precambrian palynofossils facilitate assignment of Precambrian-Cambrian age to the Kaladgi sediments investigated. Based on the microfossils data intertidal shallow marine depositional environment is envisaged.

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M. N. Viswanathiah ¹, T. R. Sreedhara Murthy ¹

Affiliations
1 Department of Geology, Manasa Gangotri, Mysore 570006, IN

Abstract

Stromatolite bearing dolomites are exposed around Tolmatti and Hodlur near Biligi (Lat 16°21', Long 75°37'). Collenia sp.; branched Collenia, Collenia Columnaris, Collenia symmetrica and Oncolites have been identified in Tolmatti Formation of Kaladgi Group.

The specific characters like gross form of colonies, nature and size of laminae, disposition of laminations, differences in fabric of stromatolites and associated dolomites, physico-chemical conditions prevailing during the formation of stromatolites and the role of physiological and biochemical factors in the initiation and development of algal structures are discussed.

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M. N. Viswanathiah ¹, J. C. V. Sastri ¹

Affiliations
1 Department of Geology, Manasa Gangotri, Mysore-570006, IN

Abstract

Specific capacities of forty wells from the hard rocks of Karnataka-granites (19 to 103 Ipm/m drawdown) ; basalts (13 to 199 Ipm/m drawdown); Bhima limestones (12 to 180 Ipm/m drawdown); laterites overlying basalts (3 to 223 Ipm/m drawndown); Bhima shales (9 to 55 Ipm/m drawdown) and chlorite schists (29 to 135 Ipm/m drawdown) have been determined. The yield of wells in general ranges from 35 to 199 klpd from these tested wells. It is found that in general (i) specific capacity increases with an increase in cross-sectional area of the wells and (ii) specific capacity decreases with increase in recovery time.

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M. N. Viswanathiah ¹, M. A. Shankara ¹, A. S. Janardhan ²

Affiliations
1 The Mineralogical Institute, Manasa Gangotri, Mysore - 570006, IN
2 Department of Geology, Manasa Gangotri, Mysore-570006, IN

Abstract

The green garnets found in the calc-silicate horizons around Bandihalli, is a chrome grossular (∼7% Cr₂O₃) with appreciable amount of Mn content. Thus, a partial miscibility between uvarovite and spessartite end members appears possible. The occurrence of thin band of graphite bearing quartzite within the calc-silicate horizons points to its metasedimentary origin. The presence of another variety of garnet (pyrope-almandine rich) in the associated cordierite bearing rock of the area shows that the composition of garnet may not be wholly dependant on grade of metamorphism.

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M. N. Viswanathiah ¹, V. Venkatachalapathy ¹

Affiliations
1 Department of Geology, Manasa Gangotri, Mysore, 570006, IN

Abstract

The banded ferruginous quartzites of the Bababudan hills, for the first time, after palynological probe have revealed the Occurrence of microbiota. 13 forms of specific and nonspecific taxonomic categories have been described and illustrated. Age relationships of the microbiota and the origin of the iron formation are discussed.

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M. N. Viswanathiah ¹, V. Vankatachalapathy ¹, A. P. Mahalakshmamma ¹

Affiliations
1 Department of Geology, Manasa Gangotri, Mysore, IN

Abstract

Palynological probe of certain samples of ancient schistose rocks of Sargur, Mysore district, have revealed microstructures similar to forms described from the Onverwacht and Fig Tree Series of South Africa.

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M. N. Viswanathiah ¹, V. Venkatachalapathy ¹, Amtul Khadeer ¹

Affiliations
1 Department of Geology, University of Mysore, Manasa Gangotri, Mysore, IN

Abstract

Occurrence of a number of micro-organic remains belonging to Coccoidal nannofossils, Acritarchs and other forms is recorded from the quartz-arenites of Badami Group, Karnataka. The fossils consist of 22 taxa classifiable into the following 9 genera, besides organic plates and cells: Micrhystridium, Granomarginata, Baltisphaeridium, Lophosphaeridium, Protosphaeridium, Tasmanities, Gloeocapsamorpha, Protoleiosphaeridium and Polyedrosphaeridium.

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