eChapters

Abstract

The Tamil Nadu is one of the leading states in groundwater development. Since the surface water resources have been fully exploited for irrigation, the groundwater is massively mined for agriculture, domestic and industrial purposes. The paper provides a synthesis of whole groundwater related issues including basin wise groundwater conditions, the aquifer types, geogenic water quality and quality deterioration due to anthropogenic activities, need for recharge, the utility of Remote Sensing & GIS etc. The paper has come out with set of recommendations as the concluding remarks.

Abstract

The state of Tamil Nadu has a low easterly gradient slope and there are number of rivers, big and small originate from the west flow towards east south easterly and confluence the Bay of Bengal. These were grouped into seventeen major and minor river basins, the Cauvery being the largest basin and the river is also a near perennial river. These river basins receive rainfall both from the southwest and northeast monsoons. The state has over 40,000 surface water bodies and number of major dams and reservoirs. Even then, since the rainfall of the north east monsoon, the major source of water source to these basins, occurs in short span of few days with high rainfall, neither adequate storage is there to store them nor the recharge possibility is available, thus all leading to flooding and wastage. The 40,000 and odd water bodies are heavily silted and polluted too. The paper provides an over view of all these, basin wise, and in addition, strongly advocates intra state river linkage and improvised irrigation management as the best option to save the state from its water deficiency.

Abstract

The Mesozoic sediments contribute around 54% of the oil and 44% of the gas reserves of the world (Bois et al. 1982). Indian Mesozoic basins occupy an area of about 400 x 103 sq. km and are characterized as frontier basins under category II - IV. These basins are mostly overlain by the Deccan Traps of Late Cretaceous age and are least explored. Deccan Syneclise is one of the largest Mesozoic basins in India, covering an area of ~ 273 x 103 sq. km. Geophysical studies have inferred hidden sub-trappean Mesozoic sediments with thickness up to 2.5 km. It is considered that requisite heat generation due to Deccan Trap volcanism soon after the Cretaceous sedimentation may have acted as a catalyst in hydrocarbon generation. Surface geochemical prospecting surveys along with carbon isotopic studies have been used to assess hydrocarbon generation potential of this part of the basin. The area adjoining Nandurbar beneath Narmada-Tapti region of Deccan Syneclise was selected for geochemical studies where geophysical studies have shown considerable sediment thickness. Surface geochemical studies indicate the generation of light gaseous hydrocarbons, C1 and SC2+ in the range of 3 to 1187 ppb and 1 to 1449 ppb, respectively. The carbon isotopic signatures of selected soil gas samples dC13 CH4 in the range of - 24 to -39.4‰ PDB) suggest thermogenic origin

Abstract

Sabatayn basin is one of the two mature basins producing oil and gas in Yemen. Due to the recent decline in oil production, the exploration activities have been extensively concentrated mainly on these two basins (Sabatayn and Sayun-Masilah). So, this present study has been conducted to evaluate the exploration potential of the remaining trap areas within these mature basins. Fractured basement of reservoir becomes very attractive exploration target in Yemen recently, after the recent discoveries of basement fractured oil fields. As the evaluation of basement traps needs time and fund, to reduce the same, this research study uses a new technique which was devised with the help of Geoinformatics by analyzing the surface and subsurface lineaments effectively. In this study, a satellite image Enhanced Thematic Mapper (ETM+7) based analysis was conducted for extracting surface lineaments, and for the subsurface lineaments, the basement lineaments were extracted from seismic, magnetic and gravity data. An orientation analysis of these surface and subsurface linear features was performed to detect the basic structural grains of the study area. The correlation between these structural grains and subsurface oil and gas traps was performed to understand the connectivity to the reservoirs. This paper discusses in detail about the same and the importance of using surface and subsurface lineament analysis for delineating hydrocarbon reservoirs in the study area.

Abstract

The Pudukkottai district located in the southeastern tip of Tamil Nadu, India provides a complex geological setting with three litho-tectonic blocks membered by the hard Crystalline rocks of Archaeozoic-Proterozoic Era in the west,Mio-Pliocene Sandstone/Cuddalore Sandstone in the centre and Quaternary sediments in the east. While the western and central blocks are separated by a well-defined NNE-SSW trending fault, the central Mio-Pliocene Sandstone block is cut into two parts by a N-S fault with western static block and the eastern uplifted counterpart. Besides the above, the various drainage anomalies viz; Annular, Deflected and Eyed drainages and compressed meanders interpreted using the raw and digitally enhanced satellite multispectral data show that the N-S oriented faults with oscillations from NNW-SSE to NNE-SSW, NE-SW and E-W orientations are tectonically active in the area. The integration of these active faults with known geothermal springs and the maxima axes drawn from the contours deducted from the temperature of groundwater measured during the predawn hours from the wells revealed that the N-S and NE-SW faults are the probable locales for geothermal resources in the study area. Thus the study demonstrates a newer methodology for locating the geothermal prospects.

Abstract

The emergence of Remote Sensing and GIS technologies has substantially eased the problems of groundwater targeting in hard rock aquifer systems. Proper utilization of these can provide more vital information in managing such scarce resource. In this context, a new technique of GIS based visualization of groundwater levels of different periods (1985- 1990 -1995) was attempted for a part of Western Ghats hill-plain region of Tamil Nadu and various groundwater features viz: ridges, valleys, domes and basins were interpreted. The integration of such groundwater features of different periods and their analysis with structural features provided some newer information on geosystem processes and their interface dynamics with hydrosystems, from which, certain strategies were suggested for better groundwater management in hard rock areas.

Abstract

The study area falls in the southern part of the Indian Peninsular comprising hard crystalline rocks of Archaeozoic and Proterozoic Era. In the present study, the GIS based 3D visualizations of gravity, magnetic, resistivity and topographic datasets were made and therefrom the basement lineaments, shallow subsurface lineaments and surface lineaments/faults were interpreted. These lineaments were classified as category-1 i.e. exclusively surface lineaments, category-2 i.e. surface lineaments having connectivity with shallow subsurface lineaments and category-3 i.e. surface lineaments having connectivity with shallow subsurface lineaments and basement lineaments. These three classified lineaments were analyzed in conjunction with known mineral occurrences and historical seismicity of the study area in GIS environment. The study revealed that the category-3 NNE-SSW to NE-SW lineaments have greater control over the mineral occurrences and the N-S, NNE-SSW and NE-SW faults/lineaments control the seismicities in the study area.

Abstract

The strenuous field trekking, inaccessibility, perception of geology only within the visibility range of the eyes etc. have remained matters of major constraints in the past in field based geological mapping. The remote sensing technology not only eradicated these but also provided lot many newer vistas in the field of geology. In addition, the application of such unique technology has brought out a hierarchy of newer concepts in the field of geology. The paper narrates the newer knowledge gathered on the geology of South India in the post remote sensing Era.

Abstract

This paper sets out to describe key results and experiences obtained during the assessment of the crop response to water which varies strongly from crop to crop depending on its specific genetic characteristics and adaptation to ecological conditions. The specific crop water information for the different crops is compiled in a crop-based data base. This includes crop water parameters, yield response to water, as well as selection of economy crops. Existing natural water resources can sustain the crop production with high yield as well as economic value with minimal environment impact. Most of the crop varieties get all of its required water from rainfall- water but due to climate change there is always a demand of irrigation water from the ground water resources. Thus, there is a need to evaluate the crop water information in relation to ground water extraction as a source of irrigation.

Abstract

Groundwater flow modeling in hydrological sciences is one of the main tools used to assess the resource potential in terms of quantity and to predict the future impacts under different stresses/scenarios. This case study is prepared to present the  groundwater flow model for the Osian-Mandore pilot area with 12 villages of Mandore Block and 21 village of Osian Block in Jodhpur district of Rajasthan. The spatial model parameters and spatio-temporal fluxes were acquired and processed using remote sensing, GIS and Groundwater flow modeling interfaces. MODFLOW software was used to model the groundwater flow system in three interfaces PMWIN 5.3.0, Groundwater Modeling System and Visual MODFLOW. 

Abstract

Conversion of an already arid land into a desert through indiscriminate human actions magnified by droughts. Such actions include overgrazing, repeated burning, intensive farming, and stripping of vegetation for firewood. One quarter of the earth’s surface is threatened by desertification - an area of over 3.6 billion hectares. Since 1990, Six million hectares of productive land are lost every year due to land degradation. Desertification threatens the liveihoods of more than one billion people and has already made over 135 million people homeless. Desertification does not occur in linear, easily mappable patterns. Deserts advance erratically, forming patches on their borders. Areas far from natural deserts can degrade quickly to barren soil, rock, or sand through poor land management.

Abstract

This paper is the result of strong belief that if earth observation and geospatial techniques could be applied to a village to plan its natural resources in sustainable manner, the potential of this technique for common man is harnessed maximum. So analysis of one village natural environment, predicting its impact on humans, identifying certain possible inhabitable conditions due to existing nature & suggesting ways to utilize these conditions for sustainable human's and nature's existence  is the motive behind this work.

Abstract
 
The definition of what drought is and what drought is not, has profound implications for the environment and all segments of society, yet it may be different for each. Many attempts have been made to develop a comprehensive and meaningful definition. A generic definition provides a starting point:  Drought is a persistent and abnormal moisture deficiency having adverse impacts on vegetation, animals, and people. The public perceives “drought” as a serious departure from normal water conditions, a departure that requires a public response to reduce negative impacts. About two thirds of the geographic area of India receives low rainfall (less than 1000 mm), which is also characterized by uneven and erratic distributions.

Abstract

Groundwater is one of the major sources of exploitation in arid and semi -arid regions of Rajasthan. To protect groundwater, its data on spatial distribution are important along with quantity. Analysis of quality of groundwater is also very important, because the physical and chemical characteristics of groundwater determine its suitability for agricultural, industrial and domestic usages. The importance ground water increases many fold for arid tracts like Western Rajasthan. Here quality of water is also matter of serious concern. Geostatistics methods are most advanced techniques for interpolation of Groundwater quality. The present study appraises the groundwater quality of western Rajasthan for agricultural purpose with GIS technology. Kriging Raster Interpolation technique of spatial analyst module in Arc GIS software has been used to generate the spatial distribution map of ground water for agricultural purpose. In western Rajasthan only 28% (58109 km2) of ground water falls under the category of good and is suitable for agricultural use. 

Abstract

This study evaluates the potential of remote sensing techniques for assessing the relationship between land degradation and poverty in Pali development block of Rajasthan. Due to climatic conditions that prevail in this area of the country, less facilities and management practices to conserve land and its fertility becomes an important factor for intensifying poverty. The other countenance of this is that it is poverty which leads to land degradation. This paper assesses the impact of poverty and land degradation on each other. The desertification intensity and BPL density is calculated and relation is seen using Chi square test. The goodness of fit is seen up to 5 per cent level of significance for land degradation and demographic data.  The desertification in agricultural area is also considered. The total degradation in the block calculated is 8.39 per cent. It is found that village with highest BPL density has more degradation intensity particularly in agricultural area, proving the agricultural based economy of the dry lands in Rajasthan. An example study is also done at village level.  Using cadastral map and satellite image classification, fields that require immediate attention have been identified. Demographic and degradation maps are also prepared.

1.0 Introduction

Population in dry lands of the world is increasing; more fresh water is required in order to meet the growing demands. To meet this challenging situation developing new technologies for identification of potential sites for rainwater harvesting (RWH) is an important step towards maximizing water availability in semi-arid areas.

Abstract

Population of Rajasthan as per Census 2011 is 68,621,012 persons which is much higher than census 2001 that records 56,507,188. It includes 12 districts of Rajasthan. Western Rajasthan covers about 61% area of the total geographical area and 39.51% population of the total population of the Rajasthan. The growth rate of population is much higher than that of the Rajasthan State. In the census 1981 Western Rajasthan had registered a phenomenal increase of 35.48 per cent over 1971 population. Regional pattern of growth rate in western Rajasthan shows that extreme hot arid region district (Barmer) is on top having 32.55 per cent growth rate whereas Indira Gandhi Canal Region (Ganganagar) district has least population growth of 10.06 per cent only. In 1981, the average urban growth rate had been 54.52 per cent. In 2001, the rural density of population was 83 persons per sq. km.

Introduction

Agriculture contributes to 29.93% of India's GDP with a share of 27% of the world's agriculture production. India is ranked 6th in the world. In Rajasthan significant portion of economy of is agrarian. The agriculture sector of the state accounts for 22.5% share of agriculture in GSDP which is estimated to 18.39% in 2009-10. About 80% of the total population resides in rural area and largely dependent on agriculture as the source of their livelihood. The hot arid region of western Rajasthan occupies 61% of the total geographical area and 39.51% population of the state. During the last four decades the burgeoning human and livestock population and increased societal demands for land based products led to  significant expansion and intensification of agriculture by putting even marginal lands under plough, excessive exploitation  of ground water and importing of surface water for irrigation.

Abstract

Quality of water is a matter of serious concern for arid and semi arid region like Rajasthan. The study area chosen is extreme western arid part of Rajasthan state where water quality and quantity both are very important issues. Due to absence of any perennial river, scanty rainfall and scarcity of surface water resources, ground water is very deep and saline. The groundwater potability assessment was based on 1119 wells water quality data. The purposes of this investigation were (1) to provide an overview of present groundwater quality and (2) to determine spatial distribution of groundwater quality parameters which affect water potability and (3) to map groundwater potability in the study area by using GIS and Geostatistics techniques. Arc GIS 9.3 and Arc GIS Geostatistical Analyst were used for generation of various thematic maps and Arc GIS Spatial Analyst to produce the final groundwater potability map.

Abstract

Droughts are normal recurring climatic phenomena that vary in space, time, and intensity. The spatial and temporal variability and multiple impacts of droughts provide challenges for mapping and monitoring on regional scales. Large historical datasets are required in drought studies to understand the complex inter-relationship between the climatic and meteorological data. Extraction of valuable information from such large data archives demands an automated and efficient way. Data mining is answer to above problem as it has the potential to search for hidden pattern and identify the relationship between the datasets. For the current research, rainfall data from 1951-2006 was used to compute Standardized Precipitation Index (SPI) and NOAA-AVHRR NDVI images for the period 1981-2006 was used to calculate Vegetation Condition Index (VCI). SPI and VCI were used as input parameters in the Apriori Algorithm for generating the association rules. Interesting rules were developed identifying the relationship between user-specified target episodes and meteorological events. Therefore, spatial and temporal pattern of drought was achieved with 88% confidence.