A Note on Barytes Mineralization in Pungarh Region, District Pali, Rajasthan
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International Journal of Remote Sensing & Geoscience (IJRSG) www.ijrsg.com A NOTE ON BARYTES MINERALIZATION IN PUNGARH REGION, DISTRICT PALI, RAJASTHAN Brijendra Singh Gahlot & P. C. Avadich, Department of Geology, Mohanlal Sukhadia University, Udaipur, Rajasthan. [email protected] Abstract Rajasthan (Table 1).The barytes mineralization is associated with igneous, sedimentary and Barytes is an important modern day industrial metamorphic rocks. It occurs as veins, cavity – mineral. Barytes mineralization is found in filling, bedded and residual deposits. different Precambrian units of Rajasthan. Table 1: Association of Barytes mineralization in sub-divisions In Punagarh hill region, barytes mineralization of the Precambrian of Rajasthan. is hosted by Sojat Formation of Delhi Supergroup. Geologic Unit Locality District It occurs as vein deposit showing various forms Malani Karara Jalore viz. linked veins, parallel veins, fan shaped, chambered vein. Vugs and other cavity filling Suite textures are also observed associated with Vindhyan Bhander Jogniyamata mineralization. The mineralization has undergone Supergroup Group Chittorgarh post deposition tectonism as evidenced by Rewa Group Jawarakalan granulation of barytes grains. The barytes mineralization is epigenetic. The Punagarh Punagarh Pali hydrothermal solutions have been derived from Group Hill the Erinpura granite intrusive into Sojat Ajabgarh Alwar & Sikar & Formation. Delhi Group Rajgarh Alwar Keywords: Barytes, Delhi Supergroup, Punagarh Supergroup Group, Sojat Formation, Epigenetic, veins belts Alwar Group Introduction Raialo Group Hathauri Bharatpur Aravalli Debari Delwara Udaipur Barytes, an important modern industrial Supergroup Group region mineral in present day industry. It is mainly used in oil well drilling due to its high specific gravity, Ranthambhor Anupura Chittorgarh low hardness, inertness to acids, insolubility in Group water and most important its lowest cost compare Rajpura Dariba- Rajsamand to other heavy materials. Bhilwara Group/ Rajpura In the global scenario India is endowed with third position in terms of reserves and second in Supergroup Jahazpur Umar Bundi production of barytes. Mangampet in Andhra Group Pradesh is the world’s largest single barytes Mangalwar Relpataliya Udaipur deposit with 68.4 million tonnes of recoverable reserves (IBM, 2015)[1]. In Rajasthan, occurrences Complex of barytes are known in Alwar, Bharatpur, Study Area Bhilwara, Bundi, Chittorgarh, Jalore, Pali, Sikar, Sirohi, and Udaipur districts where as important The present study area is located 12 km ENE of deposits are limited to Alwar, Bharatpur, Pali and the District town of Pali (E 73° 26' 26" : N 25° Udaipur districts. Geologically, barytes is found in 48'10") and lies wholly within the scope of Survey all the major sub-divisions of the Precambrian of of India topo sheet, No. 45G/5 (Figure 1). Access ISSN No: 2319-3484 Volume 4, Issue 2, March 2015 14 International Journal of Remote Sensing & Geoscience (IJRSG) www.ijrsg.com into the area is by way of National Highway NH- Later workers placed the Punagarh Group as 14, from where the interior parts of the study area the youngest group in Delhi Supergroup. Gupta are linked by minor tar-roads. The nearest rail et.al (1981)[2] Roy (1988)[4], Gupta et.al (1995)[5], links are the stations at Pali, Marwar Junction and Roy and Sharma (1996)[6], Roy and Jahakar Bumadra, even as the nearest airport is at Jodhpur, (2002)[7] placed Punagarh Group and its time some 60 km to the northwest. equivalent Sindreth Group at a much higher stratigraphic position whose volcanic phase was dated 780 Ma (Roy and Sharma, 1996)[6]. Chore and Mohanty (1998)[8] separated the Sojat Formation from Punagarh Group, containing bimodal volcanics, volcanoclastics and terrginous sediments. The contact is marked by shear zones. An age distinction between the two is indicated by absence of granite within the Punagarh Group where as the Sojat Formation containing slates and phyllites has been invariably intruded by Erinpura granite (Table 2). Table 2: Stratigraphic succession of study area (After Chore & Figure 2: Location map of Study area (part of Survey of India Mohanty, 1998). Toposheet no 45G/5). Intrusives Dolerite and felsic dykes Sowaniya Shale, repetitive sequence Regional Geology of the area Formation of basalt, rhyolite and gritty quartzite The study area falls in the Delhi Fold Belt and Khamal Shale, dacite and quartzite has been included in Punagarh Group of rocks Formation (Gupta et al., 1981)[2]. The rocks are exposed to Bambholai Pillowed basalt, jaspery Punagarh Group the west of the Main Delhi Synclinorium and Formation quartzite and shale separated by a stretch of Erinpura granite. The -------------------Unconformity--------------- Punagarh Group overlies the Kumbhalgarh and Erinpura Granite/ Gneiss Sirohi Groups (Gupta et. al., 1997)[3] and occurs Shale, slate and Sojat Formation as a roughly oval shaped outcrop from metatuff Dhangarwas in the north to Bumadra in the south and from Punagarh in the east to Bhagasar in the Geology of the area west (Figure 2). Gupta et al., (1981)[2], has divided the rocks of The rocks of the Sojat Formation represented the Punagarh Group into four formations namely by a succession of variegated shales, sandy slates, Sojat, Bambholai, Khamal and Sowaniya phyllites, mica schist, ferruginous and brecciated Formations. The Punagarh Group comprises quartz-rock at places cherty and minor dolomite. slates, phyllites and quartzites of Sojat Formation The soft and easily amenable to erosion viz. slate, with synsedimentational basic volcanics of the phyllites and mica schist are generally exposed in Bambholai, Khamal and Sowaniya Formations. the plains. The Bambholai Formation is characterized by Near Sojat and Punagarh Hill, the rocks due to synsedimentational pillow basalt of tholeiite to the hard rock capping are still preserved on alkali basalt type. Similarly the basic volcanics of hillocks. The ferruginous and brecciated quartz- Khamal Formation have been identified as having rock at places cherty occurs as irregular lenses and alkaline character. The synsedimentational veins within the slates and phyllites along the volcanic rock of the Sowaniya Formation is also western flank of the Punagarh Hill (Figure 3). The tholeiitic basalt. rock is light-grey to spotted and brownish in color and consists of opalescent quartz, light- to pink ISSN No: 2319-3484 Volume 4, Issue 2, March 2015 15 International Journal of Remote Sensing & Geoscience (IJRSG) www.ijrsg.com Figure 3 Simplified regional geology of the Study area (Modified after Chore and Mohanty -1998) showing the distribution of various units in Punagarh Group of Delhi Supergroup. ISSN No: 2319-3484 Volume 4, Issue 2, March 2015 16 International Journal of Remote Sensing & Geoscience (IJRSG) www.ijrsg.com color and at few places yellow colored barytes, rock indicates a zone of shearing. The general red jasper, limonite and hematite. Besides trend of this shear zone varies from N10° to smaller veins, there are about 16 lenses of 35 30°E and S10° to 30°W and is parallel to N20°- cm to 12 m in width and maximum of 500m in 40°E and S20°-40°W. length. Nature of Mineralization The barytes occurs as irregular lenses, thick massive veins, or in the form of small veinlets, long rod shaped grains and stringers along the foliation plane/ joints and fracture planes in brecciated quartz barytes rock and at a contact of slates (Plate 1). A total of 34 lenses and veins of barytes were observed and most of them are clustered in the western flank of the Punagarh hill. The thickness of the mineralization zone varies from 2 to 10 meters. The thickness of the individual barytes vein varies from 2 cm to 25 cm, while length of the individual vein extends up to 5 meter. At few places barytes veins runs parallel and at different orientation (Plate 2) and shows angular relationship with each other. The general trend of these barytes veins are N20-400 W but few are trending N20-600E. The important mineralization structures observed in the area are as follows; Figure 3: Geological map of the Study area. Veins: A tabular or sheet like body of mineral which has formed along fissures in rocks. Structure Fractured filled veins are produced where the mineralization has occurred along narrow The area forms a doubly plunging syncline, openings. with two closures, one located near Punagarh Linked veins: When individual fractures are hill in south and the other at Khamal in the linked by diagonal veinlets, they are called north. The syncline plunges at moderate angle linked veins (Plate 3). (250- 300) towards NNE and SSW. The Fan shaped: When veins radiating from one attitudes are variable due to folding and the base and spread like fan (Plate 4). regional strike is NNE- SSW. Bedding is well Chambered veins: when the walls of fissures seen in slates. The dip varies 10°-80° towards are not straight and parallel but are irregular and east or west according to the limbs of the folds. brecciated. The fragments of different shape and The slates in the area are highly folded and size of the host rock are caught up in both macroscopic and microscopic folds are mineralization. The caught up fragments may found. In the Punagarh Hill area itself are two have orientation differing from the host rock. anticlines and a syncline. These folds are Such veins are known as chambered veins asymmetrical and trend in NE- SW direction. (Plate 5). They plunge at 10°-60° towards south-west. Crustified veins: successive deposition of one Axial plane foliation is well developed. The or more mineral crusts on two walls of fissure general trend varies from N20°-40°E - S20°- opening gives rise to crustified veins. The first 40°W with high dips, mostly 60°-80 formed minerals will be deposited on the vein towards east. The brecciated quartz-barytes walls followed by successive minerals layers ISSN No: 2319-3484 Volume 4, Issue 2, March 2015 17 International Journal of Remote Sensing & Geoscience (IJRSG) www.ijrsg.com towards the centre of the cavity.