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1.
An area of 2500 sq. Km. has been covered by photogeological mapping with selected field checks which forms a part of Cuddapah basin in the Kumool and Prakasam Districts of A.P. The rocks exposed in the area belong to the Cumbum and Bairankonda Formations of Cuddapah Super Group. They occur more or less as an alternating sequence. These formations are bound on the east by Dharawar gneisses and on the west by Nandyal Shales. The Bairankonda Formation is predominantly arenaceous with quartzite as the main member, being easily identifiable in the aerial photographs by its characteristic topography, coarse drainage, light grey tone etc. The Cumbum Formation is mainly argillaceous with slate/phyllite as the main member, intercalated with minor quartzite band and is expressed on the photographs in dark tone with dendritic to sub-parellel drainage and occurs relatively at lower elevations, mostly in plains. The Dharwar (Archaean) gneisses underlying the vast plains in the east are recognised by the sandy nature of soil and by the thrusted contact of this unit with the Bairankondas. The Nandyal Shales occupying the large cultivated area in west have a darker tone and a dendritic drainage pattern. They are Upper Kurnool in age. All the litho-units have undergone pre-Kurnool deformation resulting into plunging/doubly plunging antiforms and synforms trending NNE-SSW and a few shear zones and faults. Due to severe deformation a very prominant foliation has developed in the Cumbum unit. Groove lineation has also been developed in the hinge portions of major folds. The magmatic activity in these formations has been witnessed with the emplacement of reibeckite syenite and Kimberlite plugs and veins. Geomorphologically the area may be divided into two prominant units namely (i) Denudational landforms comprising (a) hills, ridges, inselbergs, bornhardts and hogbacks on Bairankonda quartzites and phyllites (b) pediment and dissected pediment on Cumbum Shales and Dharwar gneisses and (ii) Depositional landforms such as (a) alluvial fans and colluvial fans (b) alluvial valley fills along river courses and (c) sand dunes in Dharwar gneisses.  相似文献   

2.
The geological studies of the eastern parts of Harda-Barwah basin covering about 3000 sq. km area on 1∶50,000 scale have been carried out using satellite imagery of IRS (FCC), supplemented by Landsat TM/MSS scences and air photos. The present studies with the aid of satellite imagery and remote sensing techniques have brought out the regional stratigraphy and structure of the area and helped in deciphering the interrelationship of various rock groups in the Narmada lineament zone. The area comprises Archaean/Proterozoic gneisses, the Mahakoshal volcano sedimentary suite, the Harda granitoids, the Bijawar Group and the rocks of Vindhyan Supergroup, Deccan Trap and Quaternary sediments. The Archaean/Proterozoic rocks comprising gneisses and schist form basement. The Mahakoshal Group of rocks occur along the ENE-WSW to E-W trending Narmada lineament zone and comprise foliated quartzite, actinolite-chlorite-sericite phyllite and metabasics. The Harda granitoids showing intrusive relationship with earlier rocks, comprise coarse-grained crudely foliated grey to pink granites, fine to medium grained homogeneous granites and porphyritic granites. The Bijawar Group comprises quarzite, chert breccia and dolomite in the order of younging and shows unconformable relationship with the Mahakoshal and the Harda granitoids. The Bijawar rocks show doubly plunging major synformal structure and numerous sympathetic minor folds along ENE-WSW to E-W axis and cross folds along NW-SW axis. The Bijawar rocks are unconformably overlain by a sequence of sandstone and shales belonging to the Rewa Group of the Vindhyan Supergroup. The Deccan Trap lava flows represent the last igneous activity in the area. The Quaternary deposits comprising a cyclic sequence of sand, silt, clay and rock gravels of the Narmada river represent the youngest formation of the area.  相似文献   

3.
基于ASTER遥感影像的西昆仑岩性信息提取方法研究   总被引：1，自引：0，他引：1  
基于西昆仑西段布伦口地区各岩性段内岩石样品的矿物组成及其光谱特征分析,提取代表各岩性单元的岩性端元波谱曲线;对研究区内ASTER可见光(VNIR)和短波红外(SWIR)数据进行匹配滤波处理,成功提取了研究区内9种重要的岩性单元(包括古元古界布仑阔勒群的黑云石英岩、黑云斜长片麻岩、黑云石英片岩和黑云角闪斜长片麻岩,志留系温泉沟群的绿泥石绢云母板岩、黑色千枚岩和绢云母石英片岩,以及石英闪长岩和英云闪长岩)。经已知地质资料和野外查证资料分析证明,用上述方法提取岩性信息的结果可靠,能为岩性填图及矿床勘查工作提供参考。  相似文献   

4.
The rough terrain between the Gogar Dhar (Mandi-Brot rise) and the Kullu-Larji valley is geologically unexplored. This paper brings out for the first time the geology and regional tectonic set-up of the area on the basis of LANDSAT imagery interpretation and field checks. Image analysis of about 3700 sq. km area and field observations along selected sections of the area reveal that the area mainly comprises mica-chlorite schists, quartzites and phyllites i.e. low to medium grade Chail metamorophics with acid and basic intrusions within them. Structually the rocks are arranged in the form of a NNW-SSE trending faulted synclinorium, the axis of which passes through Daggi Dhar. The western flank of the synclinorium is more strongly folded. Granitoids and basics show concordent relations with the country rocks. Two belts of granitoids are found occupying the cores of the folds on both the limbs of the synclinorium. Along the Uhl river (in the Chauhar valley) and the Kullu valley passes the Chail thrust separating the Chail metamorphics from the rocks of the outer carbonate belt and the traps of the Mandi unit, and the inner carbonate belt of the Larji window zone respectively. The area is dissected into blocks by cross cutting, deep-seated major faults of three generations. The fold and fault systems have prominent control over the geomorphology including the drainage patterns and landforms of the area. The present area is a typical case of inverted relief, anticlinal valleys and synclinal hills being the main geomorphic features developed due to structural control. The change in the course of the Beas River between Mandi and Pandoh is a typical case of structural control on the present drainage system.  相似文献   

5.
Photogeological studies of the area shows the presence of four major lithological groups as : 1. Precambrian basement made up of granitic gneisses and Charnockites, 2. The Utatur Group of rocks, 3. The Trichinopoly Group of rocks and 4. The Ariyalur Group of rocks. Some prominant lineaments roughly trending in NE-SW direction are seen. These lineaments represent the traces of the reactivated faults in the basemeht. The photogeological studies were supplemented by morphometric analyses. It is seen that the drainage in lower order basins is controlled by structure, i.e. by the strike of the rocks and faults in the basement. The higher order streams apparently follow the direction of regional gradient.  相似文献   

6.
Supervised classification and Crosta technique is widely used for lithological and alteration zone mapping respectively. Landsat ETM+ digital imagery has been used to generate Crosta and Supervised classification image using digital image processing (DIP) technique. In the study, The Crosta technique has been used for the first time in lithological mapping. These techniques were applied to distinguish the litho-contacts between Alwar and Ajabgarh quartzite in the south-western part of North Delhi Fold Belt (NDFB) on the basis of argillaceous and arenaceous nature of the rocks. Litho contacts between Alwar and Ajabgarh groups are varying from quartzite to biotite schist in the Khetri basin whereas in the study area the litho-contacts are Alwar quartzite to Ajabgarh quartzite which are very difficult to classify on naked eye. Therefore, this area has been selected for this study. Several authors have studied the geological setting of Khetri sub basin and classified on the basis of argillaceous, arenaceous nature and primary sedimentary structural features like ripple marks and cross bedding. This is the first attempt in the Khetri sub basin for lithological classification based on remote sensing and digital image processing technique. This study revealed that Crosta image has significant spatial correlation with the lithology discriminated using Supervised classification technique. Lithological variations were clearly demarcated using these technique around Rahunathgarh and Golyana areas. The litho units between these areas were marked under the Group of Ajabgarh quartzite by the GSI people during 1994. However, the present study classified those area under the Group of Alwar quartzite. Similar type of studies can also be carried out where these type of lithological problems arises.  相似文献   

7.
Hydromorphogeological studies have been carried out around Agnigundala mineralised belt (longitude 70°.39′ - 16°.51′ and latitude 16°.2′ - 16°.15′) using remote sensing IRS-IB and SPOT data for ground water exploration. Based on erosional and depositional characters of various geomorphic units like Hills (Structural and denudational) Pediment, Buried pediment, plains and valley fills have been identified in various lithologies like granite, granite gneiss, biotite schist, phyllite,. quartzite and dolomite. The acclamations of individual geomorphic units through visual interpretation are verified from field data. The groundwater potentials of the individual geomorphologic units have been evaluated to obtain a complete hvdrogcological picture of the area. The field data have further helped in quanlifying various geomorphological units with reference to their potential for ground water occurrence.  相似文献   

8.
Photogeomorphological mapping was carried out in parts of the lower reaches of the Jadukata-Umngi river valleys in the southern fringes of Meghalaya. The area has been divided into five geomorphic units. Topography in the area is controlled both by structure and lithology and the geomorphic features greatly facilitate in structural and lithological interpretation. This becomes quite evident from the photogeological map of the corresponding area.  相似文献   

9.
The Fatehpur Sikri area infringing the western UP, Rajasthan border was investigated for its water supply crisis in respect of poor quality and quantity as well. The study has indicated presence of two parallel quartz reefs running in NE-SW direction. Geohydrological and photogeological studies have revealed the possibility of subsurface extension of quartz reefs. However, this weathered area along reefs is promising water bearing zone. Paleo channels are also marked during studies and the area found suitable for ground water exploitation. A map showing various categories is also presented.  相似文献   

10.
In the present study, the ground water prospect of Mysore district has been delineated using remotely sensing data, base map of GSI, ground truth data, and geographic information system. Based on these integrated studies, it has been noticed that the lithology of the area mainly represents by amphibolite schists, hornblende-biotite gneiss, chamockite, quartzite and granite belonging to Archean to Lower Proterozoic. Resent alluvial deposits mainly occur as valley fills. Major lineaments are mainly confined to valley regions. Structurally the erosional and depositional landforms are occurring as hills, ridges, weathered pediments, weathered pediplains and valley fills. Geonaorphology, lineaments, drainage density, type of lithology and surface water bodies are directly influencing the ground water conditions and it is very good iu valley regions and in remaining area, it is moderate to poor.  相似文献   

11.
Land use on earth's landscape primarly indicates the degree of human interferance. Though landuse is controlled by several factors like soil, hydrologic, climatic, socio-economic and political yet geology and geomorphology play an important role in shaping landforms. The landforms processes mainly depend upon inherent lithology and structure of the earth. In the present paper an attempt has been made to study a sample area by air photo-interpretation technique using stereo-models and then evolve a methodology of land use mapping like photogeological and photopedological aspects. Also in brief, environmental aspects have been discussed. A sample area of 15 sq kms has been studied. The study opens up a new dimension for appreciation of resource and landuse management  相似文献   

12.
An area of 2300 sq km s has been mapped around Bundi based on aerial photo-interpretation, with selected field checks at key areas. The oldest rocks exposed are Aravallis comprising a thick pile of argillaceous sediments with thin interbeds of quartzite. The Aravalli rocks have been subjected to two phases of folding and have undergone a low grade of metamorphism. The Vindhyan rocks which comprise arenaceons, argillaceous and calcareous sediments constitute the Kaimur, Rewa and Bhander groups. These rocks occur south of the Aravallis with a faulted contact (Great Boundary Fault) for the major part, and also with unconformable contact at places. The upliftment of the Aravallis on the northern side of the Great Boundary Fault might have created the Vindhyan Basin south of it. The movement appears to have been gradual, keeping pace with the Vindhyan sedimentation, and was possibly revived even after the Vindhyan sedimentation as evidenced by the presence of folding and faulting in Vindhyans in the vicinity of the boundary fault. Strike faulting parallel to the boundary fault is very conspicious resulting in the repetition of the Vindhyan strata in the area east of Bundi. The Vindhyans of Bundi area indicate deposition of sediments in shallow water coastal barrier and lagoonal set-up as evidenced by sedimentary features such as tabular current bedding, ripple marks, huge blankets of sandstone, alternation of shale and limestone etc. Geomorphologically the area may be divided into three units namely:-(a) Pediment on Aravallis, (b) Structural hills on Vindhyan, expressing generally as hogback and cuesta ridges and strike valleys, and (c) Piedmont and alluvial plains (Chambal valley). The photo characters of the different litho-units have been described.  相似文献   

13.
Remote sensing techniques using satellite imagery have proved to be an indispensible tool in morphometric analysis and groundwater studies. In the present area, morphometric analysis using temote sensing techniques have been carried out in Chaka river sub-basin of Manbazar Block, Purulia district, West-Bengal, which is one of the most drought affected area in West-Bengal. The parameters worked out include Bifurcation ratio (Rb), Stream length (Lu). Form factor (Rf), Circulatory ratio (Rc), and Drainage density. The morphometric analysis suggests that the area is covered by fractured, resistant, permeable rocks, the drainage network not so affected by tectonic disturbances. Using satellite imageries of LANDSAT and IRS, different hydrogeomorphological units have been delineated. The study shows that moderately weathered pediplains and valley fills are good prospective zones for groundwater exploration.  相似文献   

14.
Ground water prospecting in hard rock areas of Uttar Pradesh is quite difficult, owing to the geological and geomorphic controls of sub-surface strata on the occurrence and movement of ground water resources, and, therefore, it requires systematic investigations, mainly with the aid of remotely sensed and data, which undoubtedly provide realistic information on the hydrogeological conditions, geomorphologic features, drainage patterns etc. of any rocky area. In this paper, an endeavour has been made to locate ground water possibilities in the drought-affected, rocky terrain of the southern Mirzapur district of Uttar Pradesh, covering part of block Muirpur which is mainly characterised by the varied geological formations, including Archean complex, pre-Vindhyan matasediments and Gondwana formation, through the application of air photointerpretation technique, primarily based on the geologic/geomorphologic approach. The hydro-investigation in the area was carried out using panchromatic aerial photos of 1∶60,000 scale, chiefly to identify the drainage patterns, major geomorphic geo structural and lithological units; as these may control the ground water regime of the area, Further. the present study was also ably supported with limited field survey and hydrogeological data, for achieving reliable results.  相似文献   

15.
The study area around Saidnagar falls in Bundelkhand granitic terrain forming buried pediplain (granite derived material). The occurrence and movement of groundwater is restricted to the unconsolidated material, weathered and fractured rock. For the selection of tube-well sites, geoelectrical resistivity investigations have been carried out at the sites which are found suitable based on remote sensing and hydrogeological studies. Twenty six Vertical Electrical Soundings (VES) have been carried out by using Schlumberger electrode configuration, which have brought out 3 and 4 layered sub-surface sections. The resistivity of water-bearing weathered/fractured rocks varies from 10 to 20 ohm m, with thickness ranging from 3.4 to 75.0 m. The depth to the basement is found ranging between 6.8 and 93.0 m The integrated studies have revealed that the northern part of the study area forms groundwater prospective zone, consisting of unconsolidated water-bearing weathered material, In the southern part of the study area, weathered layer is either thin or absent and the groundwater movement and storage is restricted to the weathered/fractured zone only. This zone extends down to a depth of 3.4 to 75.0 m and may yield sufficient amount of water since it gets recharged by direct infiltration due to precipitation and percolation through Nalas.  相似文献   

16.
The present study was carried out to delineate and characterize ground water prospect zones using IRS-ID LISS-III geocoded data on 1:50,000 scale. The information on lithology, structure, geomorphology and hydrology were generated and integrated to prepare ground water prospect map for a region in western Rajasthan. The information on nature and type of aquifer, type of wells, depth range, yield range, success rate and sustainability were supplemented to form a good database for identification of favourable zone. Geographical Information system (GIS) was used to prepare database on the above layers, analysis of relationship and integrated map preparation. The study area has a complex geomorphology. The geology is dominated by rocks of post Delhi Intrusive and Quaternary sediments. On the basis of hydrogeology and geomorphic characteristics, four categories of ground water prospect zones: high, moderate, low and very low ere delineated. The high prospect zones are alluvial plains and valley fills mainly influenced by quaternary formations with yield expectation between 100-200 lpm. The moderate zone has pediment surfaces covered by shallow soil cover in addition to weathered and fractured aquifer material with expected yield of water between 50-100 lpm. The low potential zones mainly comprise inselbergs and rocky surface with expected discharge below 50 lpm. The very low prospect zones act as run-off generating zones.  相似文献   

17.
Geomorphological map is a very effective tool in management of natural resources and helps in various types of planning and developmental activities. In the present study, geomorphological map for part of the upper Baitarani river basin was prepared using aerial photographs on 1:25,000 scale, satellite imagery in the form of IRS-IA false colour composites, generated from bands, 2,3,4 and SOI topographic sheets validated by ground truth. Since large part of the study area is inaccessible, remotely sensed data have played an important role in detailed mapping. The study area is mainly underlain by Precambrian rocks. Quarternary and recent formations are confined mainly to the river valleys. The criteria adopted for the identification and grouping of landforms of specific genetic type are the overall appearance (morphography), the shape/surface geometry (morphometry). the underlying geology, relief forming processes, and association of forms. The landform units as identified and delineated on the remotely sensed data are grouped under two genetic types, denudational and fluvial. Ten landform units, each having its own features, were identified under three geomorphic domains viz. Hill, Piedmont and Plain.  相似文献   

18.
利用岩石圈挠曲均衡原理,联合海底地形模型和测高重力异常数据,采用滑动窗口导纳技术（moving window admittance technique,MWAT）计算了全球1°×1°海洋岩石圈有效弹性厚度模型。结果表明,海洋岩石圈有效弹性厚度总体较小,10 km以下区域约占70%,15 km以下约占85.4%,均值和标准差分别约为10 km和6.7 km。岩石圈有效弹性厚度20 km以上的区域主要位于海沟外隆地区,洋中脊岩石圈有效弹性厚度一般小于5 km;被动大陆边缘,如澳洲大陆南缘,岩石圈有效弹性厚度一般也较小;太平洋的海山密集分布地区,岩石圈有效弹性厚度一般为10~20 km。  相似文献   

19.
Aerial remote sensing coupled with selective field check was carried out to assess the feasibility of the Srinagar dam site, related construction works, location of Srinagar Thrust and to evaluate terrain factors that may have adverse influence on the life of the structure. The lithology of the area comprises mainly of quartzites, phyllites, basic rocks and limestones which trend WNW-ESE. The Srinagar Thrust following the regional trend passes through the centre of the area. The investigation has established the location and extension of Srinagar Thrust and other faults, and presently dormant state of Srinagar Thrust. It also links the major Kaliasaur landslide with a fault. There is a possibility that the slide would contribute a substantial amount of silt into the reservoir.  相似文献   

20.
Parts of Indogangetic alluvial plain and southern part of Simla-Himalayas were studied to evaluate the ground water potential zones through hydromorphogeological mapping using various remotely sensed data. Black and white panchromatic aerial photographs were mainly used to differentiate different lithounits whereas MSS and TM FCC were used to delineate the major trends of lineaments. IRS LISS-II CCT was used for digitally generating enhanced False Colour Composite, Principal Component and Filtered products for better correlative studies. Different rocks of Subathu and Siwalik groups form the structural hills of high to low relief which are mainly runoff zones. The alluvial fan forming piedmont zone has been further subdivided into upper and lower piedmont zones. In order to ascertain ground water movement and occurrence, the infiltration and discharge zones were established. Other local potential discharge zones were also considered. Ground water occurs under semi-confined to confined conditions and good prospects of potable water are present in the area.  相似文献   

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