Landform analysis and ground water potential in the Bist Doab area,Punjab, India

Abstract

In the Bist Doab tract of the Punjab, occurrence of ground water is controlled by geological and geomorphological features. In this study an attempt has been made to analyse different landforms and geomorphological features and to evaluate their ground water potential. The geomorphological units identified include linear ridge, structural hills, alluvial fans, piedmont plain, alluvial plain, sand dunes, flood plain, seasonal rivulets and braided river channels. The palaeochannels, ox-bows and meander scars have prominent shallow aquifers of good quality with excellent yield. The low lying alluvial plain is cropped extensively due to more moisture and/or shallow aquifers. Flood plains are potential sites for artificial recharge. Tapping off the flood plain for ground water can be easy and cheap. The run-off and recharge zones have been identified from satellite data.     

An integrated approach for groundwater potential zoning in shallow fracture zone aquifers

This study presents an integrated approach for the identification of groundwater occurrences in shallow fracture zone (SFZ) aquifers using remote-sensing, geological, and geophysical data. The Central Eastern Desert of Egypt was selected as a test site for the present study. The distribution of major faults and shear zones was extracted from a fusion image generated by injecting high-spatial resolution phased array L-band synthetic aperture radar (PALSAR) images into Landsat Enhanced Thematic Mapper images. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) digital elevation model was processed to extract the drainage systems, slope, and topographic wetness index (TWI). The multidate PALSAR imagery acquired during rainy and dry seasons was used to estimate the relative soil moisture content. The lithology, fractures, drainage density, slope, TWI, and soil moisture content were used as thematic layers for groundwater occurrence in the SFZ aquifers. A GIS model of groundwater potential was developed by selecting the most probable locations for groundwater in each layer. The results indicate that the spatial distribution of the existing water wells is in agreement with the model where all wells fall in the regions of high groundwater potential zones. A geophysical survey was conducted using ground penetrating radar (GPR), indicating that the high groundwater potential zones are promising for drilling shallow wells. The adopted approach can be used as a cost-effective tool for groundwater exploration in the SFZ aquifers in the study area and in areas of similar geologic and hydrogeologic settings elsewhere.     

Basement topography and aquifer geometry around Ken Graben,India

0 An attempt has been made to study the subsurface geological and geomorphological details of the Banda area and to demonstrate their relationship to aquifer geometry in the region. In this study a systematic analysis of a basin was made by integrating satellite data with the available spatial ground dataset using ILWIS (Integrated Land and Water Information System). The approach involved regional interpretation of geomorphological and structural features exposed at the surface and relating these to the subsurface relief. The area chosen for the study is situated within the marginal Gangetic alluvial plain in Banda district of Uttar Pradesh, India. The region has a varying thickness of alluvium composed of alternating sand/kankar (carbonate concretions) and clay strata deposited on an uneven basement. Different image processing techniques such as image smoothing, contrast stretching, false colour composite, and principal component analysis were used to enhance the lithological and geomorphic features and their effect on associated features like vegetation and soil. Subsurface features of importance in ground water exploration such as buried channels were identified. Several geomorphological features such as sand bars, point bars, meander scrolls, abandoned channels and ravines were identified and the region was classified in terms of five geomorphic units. A methodology to generate a digital elevation model of subsurface topography with the help of depth to bedrock contours is proposed. On the basis of this model, the configuration of the basement topography in the region was previously reported by the authors In this paper sites for favourable aquifer disposition and various subsurface geomorphic features which are potential sites for ground water development are identified using Geographic Information System (GIS) capabilities. An overlay of the enhanced image on a map showing the thickness of granular zones on the digital terrain model of the basement has led to an understanding of the exact subsurface geometry of the aquifers and their relationship to surficial geomorphic features. Ground water hydrogeological status has been inferred from integration of the information from structural, lithological, geological, topographic and hydrological data.     

Laboratory and field measurements of the modification of radar backscatter by sand

Over the last two decades, the use of synthetic aperture radar (SAR) to address geologic problems has expanded as new applications for radar have been developed. One of the earliest and perhaps most surprising results from orbital SAR images of the Sahara was that, under certain conditions, radar signals penetrated up to several meters of sand to reveal subsurface features such as ancient river channels. Subsequent studies of radar penetration of arid sand deposits have dealt with factors that govern the ability of radar to penetrate a sand cover. This paper presents results from a laboratory experiment in which radar backscatter from a surface of rocks was measured under controlled conditions as a function of frequency, polarization, incidence angle, and sand cover thickness. The sand used in the experiment had a moisture content of 0.28 vol.% and caused calculated average attenuations of 4.2±1 dB/m for C-band and ∼11±2 dB/m for X-band. Results from the experiment were compared to field measurements of sand thickness during acquisition of airborne radar images. In AIRSAR images, the extent of dry sand in a dune field appears best in C-band because longer wavelength L- and P-band signals penetrate thinner sand deposits. Images of wet sand (4.9 vol.%) suggest that L-band was able to penetrate thin sand even though that sand was wet. Together, these laboratory and field measurements contribute towards a better understanding of how a sand cover modifies the radar backscatter of a surface.     

Ground-penetrating radar surveying in support of archeological site investigations

In April and July of 1996, ground-penetrating radar (GPR) surveys were conducted in support of archeological investigations at Flagstaff, Arizona and Sebastian, Florida, respectively. A GSSI SIR System 8 radar unit with a 500-MHz monostatic antenna was used for both surveys.The Flagstaff, Arizona survey was conducted at Elden Pueblo Ruins. The site is located in a coniferous forest and characterized by a myriad of surficial and subsurface features. Surficial features consisted mostly of pottery shards and the remnants of rock walled structures. The subsurface features consist mostly of rock lined pits, stone walls, and grave sites covered by a soil layer of variable thickness. The soil is derived from volcanic clastics and the underlying Kaibab Limestone bedrock. GPR profiles were acquired across various locations, some of which had been previously excavated and backfilled by archeologists. The main objectives were to determine the utility of the GPR technique with respect to locating subsurface features of archeological interest, determine the optimum field parameters in the area, and direct further field work.The Sebastian, Florida survey was conducted along the Atlantic coastline. Data were acquired along five beaches and one coastal sand dune. The beaches and dunes of the area are composed of a medium to coarse grained sand, containing quartz grains and carbonates. The principle objective of the Sebastian, Florida survey was to locate wreckage from a Spanish treasure fleet. A secondary objective was to determine the utility of GPR in a near shore marine environment.     

An integrated approach to map certain palaeochannels of South India using remote sensing,geophysics, and sedimentological techniques

Palaeochannels are important sources of groundwater, economic minerals, and placer deposits. They are also good repositories of palaeoclimate data. To exploit such resources, the first essential step would be to identify and map palaeochannels. This article presents a study in which multi-sensor (optical, thermal, and microwave) image data and satellite-derived digital elevation models (DEM)s of the northern coastal region of Tamilnadu state, south India, were analysed visually and digitally to recognize exposed and buried palaeochannels. Image-enhancement techniques such as linear contrast enhancement of optical data and fusion of microwave and optical image data brought out more information about the palaeochannels. Hill-shading techniques applied to the satellite-derived DEM, further added to the information content on the existence of the palaeochannels. The existence of the newly identified palaeochannels was verified by ground-based techniques such as field checks, sedimentological analysis, and electrical resistivity surveys. The presence of well sorted and rounded grains in the sediment samples and high apparent electrical resistivity values for the thick sandy subsurface strata in these locations confirmed the existence of palaeochannels which were interpreted from the images.     

Spectral Angle Mapper and aeromagnetic data integration for gold-associated alteration zone mapping: a case study for the Central Eastern Desert Egypt

The Spectral Angle Mapper (SAM) classification technique is integrated with the surface structure and aeromagnetic data to map the potential gold mineralization sites associated within alteration zones in Central Eastern Desert (CED), Egypt. The surface reflectances of the Enhanced Thematic Mapper Plus (ETM+) and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data were classified using the SAM classifier. Five spectral reflectance curves of the alteration minerals (haematite, illite, kaolinite, chlorite, and quartz) were utilized as end-members for the SAM classification. The surface lineation, and shear zone systems were delineated using ETM+ bands. The deep-seated faults were defined using the Euler deconvolution filter on the gridded aeromagnetic data. The magnetic data analysis inferred the subsurface structural depths range from 500 m to 2000 m. Geographic information system (GIS) overlaying operation was performed using the surface lineation and the subsurface faults layers to identify the structural continuity and to extract the possible migratory pathways of the hydrothermal solutions. Within Multiple Criteria Decision Analysis (MCDA), fuzzy membership operations were applied to identify the prospective alteration sites. The mapped results were compared with global positioning system (GPS) locations of existing alteration zones. The current proposed mapping method is considered a robust tool for decision-making and potential site selection technique for further mineral exploration in CED.     

基于非连续变形分析的岩体断裂破坏过程研究

工程修建会破坏岩体结构,导致岩体结构的稳定性下降,因此需要对其检测,以保证工程施工的安全性。在此背景下,研究一种基于非连续变形分析的岩体断裂破坏过程自动检测方法。该研究以某隧道工程对山体的破坏为例,分析了该处岩体结构特征。利用探地雷达技术获取岩体裂隙的非连续变形参数,构建岩体的非连续数值模型并将变形参数插入到模型当中。对模型施加荷载,模拟分析岩体的非连续变形情况并量化岩体断裂破坏程度,包括裂隙的发展、岩体的位移以及稳定性系数,实现岩体断裂破坏过程自动检测。结果表明：裂隙均沿着虚拟节理持续扩展,最终将整个岩体分割为了三个块体,其中有两条裂隙形成了贯穿裂,使得岩体发生断裂。块体1 、块体2的断裂破坏过程主要发生在垂直方向；块体3的断裂破坏过程主要发生在水平方向。岩体整体稳定性在逐渐下降,从最初的基本稳定到100d时之间下降到稳定性差的程度。     

A comparison of the potential for using optical and SAR data for geological mapping in an arid region: The Atar site,Western Sahara,Mauritania

Our research in Mauritania focused mainly on the study of phenomena that partially or entirely masked surficial formations overlying bedrock. The analysis of ERS radar images compared to that of optical SPOT data identified geomorphological and geological objects for which the SAR provides complementary information at a regional scale; interpretation difficulties caused by, for example, shadow and lay-over phenomena; and mapping potential using geocoded ERS 1 images, notably for regional geomorphology, the sedimentology of sand bodies, and the structure of bedrock, where possible below windblown cover. The non-geocoded image must be interpreted with care to avoid the phenomenon of dip-direction inversion. The 'unwrapping of slopes' by geocoding gives a picture of the global layout of units, particularly those of the substratum in areas with medium to high topographic relief. Main faults are clearly seen on radar images at small scale and show up under conditions similar to those of optical data, but fractures that are (sub)parallel to the direction of the incident signal can be invisible on the radar data. Occasionally, the 'transparency' phenomenon enables us to 'see' below thin sand cover.     

Radar topography data reveal drainage relics in the eastern Sahara

The Shuttle Radar Topographic Mission (SRTM) elevation data reveal segments of inactive drainage channel systems in the eastern Sahara. Four sites are investigated and their drainage networks are delineated and compared with processed Synthetic Aperture Radar (SAR) and Enhanced Thematic Mapper Plus (ETM+) images. These include parts of the drainage lines that lead to the Kufra Oasis in Libya; the eastern Gilf Kebir drainage system that straddles the border region between Egypt and Sudan; the lower reach of Wadi Howar, the extinct western Nile tributary in Sudan; and a reversed flow channel of Wadi Kubbaniya northwest of Aswan in Egypt. These features are delineated using SRTM data and a Geographic Information System (GIS) hydrologic routine. The results show that the SRTM signals penetrate the desert‐sandy surfaces and map ancient drainage systems in the same way as SAR. The study also demonstrates that SRTM data can be used to confirm or modify pathways of channel courses mapped from radar images alone. Because of this capability, it is also recommended that SRTM data be used in place of GTOPO30 elevation data in hydrologic modelling of sand‐covered deserts.     

Microwave remote sensing of physically buried objects in the Negev Desert: implications for environmental research

We report remote detections of physically buried specularly reflecting objects using microwave radar at two sites: Ashalim and Tseelim in the northern region of the Negev Desert, Israel. These detections provide confirmation that microwave subsurface remote sensing is a genuine phenomenon. At Ashalim, a scatterometer operating in the P-band (441 MHz, 68 cm) was mounted on a cherry picker truck at a height of 8 m and used to detect two triangular aluminum mesh reflectors (forming a 1-m square area reflector) buried down to a depth of 8 cm in dry sand. At Tseelim, the same scatterometer was mounted on an airplane flying at an altitude of 70 m and used to detect 1-m square aluminum reflectors (each one submerged at a different location along the airplane flight path) buried down to a depth of 20 cm. The experimental results compare favorably with a theoretical model that incorporates radar absorption effects arising in the sandy subsurface layer and radar interference effects arising from phase differences between reflections from the surface and buried reflector. The theoretical modeling also predicts the detection of a subsurface reflector down to a depth of about 4.4 m. This experiment and the associated modeling approach is the first of a series of planned experiments, which we outline for the detection and the theoretical evaluation of buried reflectors using remote microwave and VHF radar. We identify potential subject areas for environmental research.     

Computer program for regression model for discontinuous structural surfaces

A regression model for discontinuous structural surfaces requires nonlinear normal equations. A computer program FAULTS is presented which estimates parameters of the regression equations. The program algorithm, which simulates possible natural-fault movements, has been tested on various multifaulted structural surfaces. The prefault geometry of subsurface structures can be reconstructed using estimates of the fault displacements.A method based on the geographic distribution of large residuals is proposed for detecting unmapped subsurface faults; a mapped fault in the Portrero oilfield (California) has been predicted accurately by this method.     

Multitemporal Landsat data applied for deciphering a megafan in northern Amazonia

In this article, we present a protocol for the recognition of channels and waterbodies and for estimating their hydroperiod to both characterize a megafan system in northern Amazonia and discuss its dynamics in the late Quaternary. Our approach is based on analysis of a multitemporal Landsat Thematic Mapper/Enhanced Thematic Mapper Plus (TM/ETM+) data set consisting of 13 scenes acquired from 2000 to 2009. The images were primarily preprocessed using standard techniques for geometric and radiometric corrections. Following numerous tests with the most common water classifiers, we determined that a simple threshold on an infrared band, which provided a binary image containing both water and non-water classes, would adequately meet the goals of this article. The sum of all 13 classifications produced a new image, the hydroperiod product, with pixel values corresponding to the relative frequency of standing water. The results indicate that there is no permanent drainage network in the Viruá megafan, which displays only temporary channels with medium flood frequency and palaeochannels. These are arranged as complex distributary networks, as is typical of megafan depositional systems. The southern part of the megafan contains distributaries that are seasonally flooded, while the central and northern parts display an increased volume of palaeochannels. These data lead us to conclude that the locus of sediment deposition along this megafan system changed from north to south through time.     

Mapping surface roughness and soil moisture using multi-angle radar imagery without ancillary data

The Integral Equation Model (IEM) is the most widely-used, physically based radar backscatter model for sparsely vegetated landscapes. In general, IEM quantifies the magnitude of backscattering as a function of moisture content and surface roughness, which are unknown, and the known radar configurations. Estimating surface roughness or soil moisture by solving the IEM with two unknowns is a classic example of under-determination and is at the core of the problems associated with the use of radar imagery coupled with IEM-like models. This study offers a solution strategy to this problem by the use of multi-angle radar images, and thus provides estimates of roughness and soil moisture without the use of ancillary field data. Results showed that radar images can provide estimates of surface soil moisture at the watershed scale with good accuracy. Results at the field scale were less accurate, likely due to the influence of image speckle. Results also showed that subsurface roughness caused by rock fragments in the study sites caused error in conventional applications of IEM based on field measurements, but was minimized by using the multi-angle approach.     

Fault tectonics of the Shillong plateau and adjoining regions,north-east India using remote sensing data

The Shillong plateau in north-east India shows innumerable fracture lineaments on satellite images. In fact the whole plateau is criss-crossed by fractures. The plateau has been subjected to extensive compressional forces mainly in N-S and E-W directions resulting from the collision of the Indian plate with the Tibetan and Burmese plates, respectively. This type of plate tectonism has been responsible for the formation of many significant faults, folds and other tectonic features in the Shillong plateau and adjoining regions. The well known E-W trending Dauki fault, N-S trending faults, NE-SW trending shear zone and other prominent lineaments and their associated structural features could be studied on the basis of remote sensing techniques. Folding in soft sediments along the Dauki fault reveals the compression direction. Directional compressional tectonism has been expressed through lateral movements along the NE-SW trending shear zone and N-S trending faults and folds in the area just south of the Hatlong thrust. It has been observed from the studies that the Dauki fault zone and the areas in Bangladesh show various tectonic features, which are mostly controlled by vertical movements. Seismicity of the Shillong plateau is quite scattered all over the area. The occurrence of several deep earthquakes (> 1OOkm) indicate deep tectonic activities in the upper mantle. Earthquakes have been found to occur near some faults and this is probably an indication of recent activities along these faults.     

Structural analysis of the main uraniferous chalcedony vein at G. El Missikat environs,Central Eastern Desert,Egypt

Abstract

This study deals with the structural analysis of joints in the uranium-bearing vein deposits and the surrounding enclosing granite rocks in G. El Missikat pluton, Central Eastern Desert, Egypt. The study includes the different structural features such as the intensity of joints, their opening and length for the different sets taken on a systematic pattern through and along the upper and lower contact of the uraniferous chalcedony vein, and their correspondence in the subsurface mining working.

The relative movement of the chalcedony vein is interpreted from slickensides striation along the enclosing fault plane. The analysis of microfolds along the fault planes also indicates the movement picture. Photolineaments are traced showing the main fracturing intensity trend in the granite pluton.

The study reveals that the main fracturing surface sets trend ENE-WSW and NW-SE stained by surface uranium mineralization. The first set in the subsurface mining working is found rotated anticlockwise relative to the surface and trends NE-SW, while the another set varies from the WNW-ESE to NW-SE trend.

The opening of the ENE-WSW surface trend and its subsurface corresponding NE-SW trend increases downwards. The last conclusion is good evidence for the possibility that uranium mineralization increases downwards. The subsequent compressional forces acted upon the area from the NW and NNW directions. The ENE shear fractures produced during the first movement were then rejuvenated, reopened and invaded with silica phases and uranium mineralization during the second movement.     

Application of terrain analysis to the mapping and spatial pattern analysis of subsurface geological fractures of Kuala Lumpur limestone bedrock,Malaysia

Subsurface geological fractures in karst terrain are often associated with unpredictable environmental and geotechnical engineering problems. This requires precise mapping and an understanding of the distribution of geological fractures on multi-scales. To extract and investigate surface and subsurface geological fractures on such scales, multi-scales, this study presents two approaches. The first involves geological prediction and visual interpretation of terrain parameters using a digital elevation model (DEM). The second is an automatic detection method using a topographical fabric algorithm that uses a DEM to create a map of ridges, which represent the footwalls of geological fractures, and valleys (channels), which reflect geological fracture zones. Unlike wavelet analysis and the Fourier transform, which use optical remote-sensing images, the integration of visual interpretation and a topographical fabric algorithm is capable of the extraction and spatial correlation of subsurface geological fractures. This method was applied to Kuala Lumpur limestone bedrock in Malaysia, by focusing on the adjacent mountainous areas and the geometries of ex-opencast mining ponds. The spatial correlation of the extracted surface geological fractures was clarified by rose diagrams and semivariogram models. Spatial correlation shows that the Malaysian peninsula, surface and subsurface geological fractures and the geometry of ex-opencast mining ponds share similar trends. The results obtained using this methodology is compared to those of subsurface geological fractures reported by means of geophysical surveying and field investigation. This proposed method may be useful for mapping geological fractures in areas of high soil moisture, where geophysical surveying is difficult and/or not available, and is also highly applicable in other parts of Malaysia or Southeast Asia, permitting a better understanding of the geotectonics and geotechnical engineering setting of the study area.     

The role of tectonic inheritance in the development of recent fracture systems,Duero Basin,Spain

A lineament analysis of the Duero Basin (north Spain) suggests that cover rocks have been influenced by a previously fractured basement in sediment cover with little deformation. The Duero Basin is covered with horizontal Neogene rocks (mainly sandstones, shales and limestones) with a total outcropping area of about 50?000?km² and a maximum thickness of 300?m. The only structures found within the Neogene are map-scale monoclines near the basin margins, and joints and faults, most of them without significant displacement. From the analysis of a Landsat Thematic Mapper (TM) scene, lineaments were mapped at the eastern half of the Duero Basin. The orientation frequency of lineaments shows an absolute maximum NE–SW to ENE–WSW, with several sub-maxima oriented E–W, NW–SE and WNW–ESE. These fracture directions controlled most of the present-day fluvial network. Within the Palaeozoic and Mesozoic rocks cropping out at the basin margins the orientation of lineaments corresponds with that of mappable faults, particularly in the Palaeozoic basement. The zones with maximum density of lineaments are associated with map-scale WNW–ESE thrusts and folds located below the horizontal Neogene. The origin of the main fracture systems in the Neogene rocks of the Duero Basin appears to be controlled by older structures, namely the NE–SW faults that cross-cut the granitic and gneissic basement of the Duero Basin and its southern and western margins. These faults are late Variscan (probably Permian) in origin and were reactivated during the Mesozoic and the Cenozoic. Their activity in Miocene and post-Miocene times is related to strike-slip and extensional movements linked to the recent intraplate stress field in the Iberian Peninsula.     

地下管道图象的自动处理和识别

对地下管道探地雷达图象给出了自动处理和识别方法,管道的位置和深度直观地显示在 计算机屏幕上,此方法已应用于一种实际探地雷达,对地下管道目标具有良好的识别能力.     

Ground penetrating abilities of a new coherent radio wave and microwave imaging spectrometer

The early use of synthetic aperture radar (SAR) and lidar systems from aircraft and space shuttles revealed the ability of the signals to penetrate the ground surface. Atomic dielectric resonance (ADR) technology was developed as an improvement over SAR and ground penetrating radar (GPR) to achieve deeper penetration of the Earth's subsurface through the creation and use of a novel type of coherent beam. When pulsed electromagnetic radio waves pass through a material, they generate measurable responses in terms of energy, frequency, and phase relationships. A deployment of the ADR equipment in a field study of a measured section of Dinantian sediments in a disused quarry at Cults, Fife, Scotland, has confirmed the ability of the method to distinguish the lithologic type and their respective thickness ranging from limestones through sandstones, siltstones, seatearths, and coals. Borehole data were used to corroborate the ADR imaging spectrometer. The signal penetrated more deeply into the ground than the 20 m height of the exposed rock section, and it showed good correlation with records from two nearby boreholes that extend to lower levels. Reliable lithological recognition at ground penetration of more than 90 m had been achieved. ADR was also deployed over deeper borehole sites in the Limestone Coal Formation at Higham and Lathones, Fife, Scotland. Here the signal was shown to penetrate the subsurface to depths of 225 and 580 m, respectively. A subsequent field deployment of ADR at Cousland, Midlothian, Scotland, demonstrated subsurface penetration in the Lower Limestone Formation by ADR to 700 m – as confirmed from nearby boreholes.