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1.
The Precambrian metamorphites of Northeastern Rajasthan belonging to Pre-Aravalli, Aravalli and Delhi Supergroups exhibit a mature topography where the physiography has faithfully depicted the major structures of area. Few important megalineaments demarcated on the imagery either represent major fault zones or the zones of intense granitic activity. Some of these are oblique to the regional strike of rocks and support drainage running in diagonally opposite direction within the same lineament, indicating thereby upheavels subsequent to the lineament formation. The lineaments fall broadly in two sets which are correlatable to the two major phases of Delhi orogeny. The lineaments of the first set trend NE-SW and are more prominent: than the NW-SE and WNW-ESE running lineaments. The major lineaments such as Sabi-Sota, Mendha and Kakor-Lalsot lineament together with other regional lineaments depict appreciable geomorphological expressions and significant geological evidences.  相似文献   

2.
The paper decribes the lineaments in the coastal area of Goa identified on aerial photographs and their correlation with the lineaments reported from the adjoining areas. The majority of lineaments along the coastal part of Goa follows a NW-SE, NE-SW and a few ENE-WSW trends. The NW-SE direction is predominant and corresponds with the regional Dharwarian trend followed by NE-SW trending linears due to cross folding of Dharwar Orogeny.  相似文献   

3.
The study of lineament pattern based on IRS-IA sub-scene (P24–R50) and Landsat (P143– R42) data combined with the drainage analysis and field observations, two prominent sets of lineament (NE-SW and NNW-SSE), besides less prominent E-W and N-S trending lineaments of tectonic origin have been observed in parts of Allahabad area. Pervasive and penetrative sub-vertical joint sets parallel to the macroscopic linear structures along with collapse structures possibly of neotectonic origin are also noted in the basement rock exposed to the SSW of Allahabad. The development of various meso- and macroscopic deformed structures, presence of collapse structure in the basement strata and the near orthogonal channel shift of axial rivers provide evidence of basement reactivation in parts of Allahabad area, Ganga plain in space and time.  相似文献   

4.
The significance of neotectonic lineaments for groundwater prospecting was studied for the area around Bhinmal — a semi-arid part of Thar desert. The application of Directional Filtering procedures on IRS LISS I Band 4 digital image of the study area revealed NE-SW, NW-SE and E-W trending lineaments which are very subtle and in two cases, even unnoticed otherwise. The use of exploratory borehole lithologs and field evidences indicated that the identified lineaments are long rectilinear buried and partly exposed channels and the intersection zones are characterised by thick lenses of coarse sand and gravel. These buried channels and zones of coarse sediments thus represent potential sites for the accumulation of freshwater during rain. The present work has highlighted the suitability of Directional Filtering procedures for lineament mapping and buried channel studies in a desertic terrain.  相似文献   

5.
Geological and geomorphological mapping was carried out for a part of Ganjam district, Orissa through visual interpretation of IRS-IB LISS II flase colour composites. Various lithounits such as khondalites, charnockites and granites of Archaean age were mapped. The study area is traversed by two sets of vertical joints — one trending in NE-SW direction and the other in NW-SE direction. Three sets of lineaments in the study area trending in NE-SW, NW-SE and ENE-WSW suggest that the study area was subject to very high degree of deformation in the past. Major geomorphic units delineated are, Hills, Pediments, Valley Fills, New Flood Plains, Old Flood Plains, New Coastal Plains and Old Coastal Plains. Different landforms under each geomorphic unit are also mapped.  相似文献   

6.
Geology in parts of Sainj Valley,Kulu district,Himachal Pradesh   总被引：1，自引：0，他引：1  
The paper highlights the findings of photogeological studies, with selective field checks, carried out in Sainj Valley. For the first time, a photogeological map of the area has been prepared using large scale aerial photographs Structurally the area forms‘Window in a Window’ structure as the oldest rocks of Kulu formation are thrusted over the younger rocks of Larji Group (Larji and Banjar formations) and further Banjars are thrusted over Larjis. Thus, Larjis being stratigraphically youngest, occupy the lowest tectonic position. The Kulu formation mainly consists of Central Crystalline, schists and gneisses. Banjar is composed of quartzite, metabasics, slate and phyllite. Larji predominantly consists of dolomite and quartzite with slate and phyllite. The photogeological studies have helped to bring out the lineament pattern, landslide zones, major structural trends and main geological formations. The lineaments mainly trend in NNE-SSW, NW-SE, NE-SW and NNW-SSE directions. A key for photo-characters of different litho units and terrain elements of the area is established.  相似文献   

7.
The role of hydrogeomorphological units and lineaments in the storage of groundwater from the Muvattupuzha river basin has been investigated using IRS ID LISS III data. Other than the usual water bodies such as river course, reservoirs and ponds, the major hydrogeomorphological units identified in this basin in the descending order of their groundwater potential are: valley fills, moderately dissected plateau, pediments, residual mounts, residual mount complex, linear ridges, residual hills and structural hills. Majority of the lineaments trends in NW-SE and WNW-ESE directions. Even though the eastern part of the basin is characterised by moderate to high lineament density, the above area is found to be poor to moderate groundwater prospect zone because of high gradient and structural hills. The pump test analyses of dug wells from different hydrogeomorphic units also confirm that valley fills are the most promising unit for groundwater prospecting than the rest.  相似文献   

8.
In the overall tectonic set up of various coal basins of the Peninsular India, the Son-Mahanadi Valley coal basins of Central India have a unique disposition. The coal measures sediments of Peninsular India are developed along well defined E-W and NW-SE trending linear narrow belts. The Son-Mahanadi Valley basins represent the tract where NW-SE trending Mahanadi Valley basins seemingly merge with the major east-west trending Damodar-Koel-Son-Satpura alignment. Landsat data of Son-Mahanadi Valley basins in the four spectral bands (0.5 to 1.1 Micrometers) were used to pick up the lineaments which are possibly of geologic origin. Detailed analysis of lineaments were carried out with the help of three softwares. Diglin (to produce rose diagram) and PLLIN (to plot digitized lineaments to produce a map on any scale) by a Hewlett Packard 45 series microcomputer equipped with graphics screen, plotter, digitiser and floppy disc unit. Detailed analysis revealed a pronounced direction roughly, N 70°E which is present in the northern half of the area while N 40°W direction is present alongwith N 70°E in the southern half. These trends correspond to the NW-SE trending Mahanadi Valley and to the E-W trending Damodar-Son Satpura belt. The above clearly brings out the striking parallelism between the lineament trends in the basement and the overlying coal bearing Gondwana Sediments. This parallelism is suggestive of a genetic relationship between the two.  相似文献   

9.
The geology of northwestern part of Indian peninsula is considered to be important due to complete preservation of rocks from Archaean to Upper Proterozoic. Further, these rocks have served as ideal host of varieties of economic minerals. The present work is an attempt to study the structurally deformed granulitic terrain in parts of Gujarat and Rajasthan in light of remote sensing. The study area falls under Sirohi, Banas Kantha and Sabar Kantha districts of Rajasthan and Gujarat. Remote sensing technique is utilized for the understanding of structural geology and deciphering the shear pattern. The methods adopted in this study include generation of False Color Composite (FCC) of satellite data, interpretation of lineaments from FCC and study the drainage pattern, structural basin delineation, profiling, and field mapping. It is observed that the area has undergone extensive deformation. There are two major sets of lineaments interpreted in the granulitic terrain such as WNW-ESE and NE-SW directions. Majority of the WNW-ESE lineaments are brittle in nature and N-S, NE-SW trending lineaments are ductile in nature. Overall the study area bifurcated into seven structural basins comprises of basic granulites, calc granulites and pelitic granulites.  相似文献   

10.
A geostatistical analysis of the remotely-sensed lineament fabric data associated with the North Almora Thrust of Garhwal Himalaya has been carried out The analysis of data provided 18 major orientations of the lineament density girdles. Further statistical treatment of these derived lineaments using the method of analysts of directional data indicates that the lineaments can be classified into genetic groups. The result indicates that the North Almora Thrust and Kaliasaur Fault are not genetically related and occurred in separate phases of tectonic activities. The results also show that the Alaknanda river is flowing through a tectonically-controlled valley. The study suggests the suitability of statistical methods in lineament-fabric-data analysis for tectonic interpretations.  相似文献   

11.
The Bundi-Indergarh sector in southeast Rajasthan is characterized by folded and faulted Vindhyan rocks that are exposed as NE-SW trending long parallel ridges. The sector is separated from older rocks by the Great Boundary Thrust and is traversed by younger cross faults at several localities. The thematic maps of geomorphology, slope, vegetation index and morphotectonic parameters of Bundi-Indergarh sector have been prepared using IRS ID L1SS III and WiFS and, Landsat ETM digital data. These theme are integrated in GIS environment to assess the neotectonic potential in the area. The neotectonic potential map of the sector has been generated that indicates relative potential values as high (55–85), medium (35–55) and low (5–35) on 100-point scale. The observed four high potential zones in the area are located at the intersection of NE-SW and NW-SE lineaments. The study brings out methodology for assessing active tectonic potential of the area.  相似文献   

12.
Aerial photo-interpretation of the area underlain by Bandelkhand gneisses, Bijawars and Vindhyans, around Madaura and Sonrai in Lalitpur Dist. of U.P., revealed the presence of a number of lineaments. During fieldwork the lineaments were found to represent ultrabasic, basic and acidic intrusions, faultzones, lithological contacts and foliation. The drainage of the area was found to be grossly controlled by these elements. Three major trends viz. NW-SE, NE-SW and E-W are observed in the area. The first two represent shear joint system, while the latter represent release fractures. This setup is visualised to be due to N-S phase of compression.  相似文献   

13.
Bist Doab interfluvial tract in the north-western part of Punjab, India, has been investigated for geomorphic signatures of active tectonics using remotely sensed data and geographical information system (GIS). The anomalous river flow, abrupt changes in flow direction, angular drainage, compressed meanders, asymmetry of river bends, high channel sinuosity, abandoned channels, water-logged and marshy areas observed along the courses of Beas and Sutlej rivers and their tributaries indicate tectonically active nature of the terrain. The strong control exercised by the NE-SW and NW-SE trending lineaments on the drainage network is well evident in the form of long straightened slope deviatory courses, definite changes in channel pattern and sharp knee bend turns taken by the seasonal rivulets. The asymmetric and elongated nature of watersheds and straight to curvilinear mountain fronts quantified through morphotectonic analysis are characteristic of tectonically active settings and further corroborate the evidence of active tectonics.  相似文献   

14.
A set of techniques was developed for automatically detecting tectonic lineaments from multi-source remotely-sensed data at various scales. The techniques include adaptive shading of grid data to enhance linear features, a segment-tracing algorithm to extract line segments from the shaded grid data, grouping of the segments by concatenating short segments, and connecting them by proximity and co-linearity criteria to form a lineament that represents significant tectonic structure. B-spline smoothing was adopted for lineament representation. Finally, a technique for assessing the orientations and styles of faulting (normal, reverse, and strike-slip types) was developed for use in characterizing the extrapolated fracture planes. The applicability of the developed techniques was examined using 30 arc-second topography/bathymetry grids, 1-min gravity anomaly grids, and 2-min total field magnetic intensity grids covering Egypt and its surroundings. Lineaments derived from data types so diverse in composition and from various depths corresponded well with the referenced tectonic features over much of the region. Prominent trends and faulting styles of lineaments provided important clues as to the timing of their development as well as strong support for a structural inheritance model. Results demonstrated the effectiveness of the developed techniques combined with integration of remotely-sensed data in detecting regional fracture systems accurately and in characterizing geodynamics over a long timeframe.  相似文献   

15.
Lineament patterns detected from remotely sensed data provide useful information to geoscientists, specially in the study of basement tectonics, groundwater targetting and mineral exploration. Improvements in the spatial resolution of satellite images have resulted in the detection of short and faint lineaments which have hitherto gone unnoticed The IRS-1A LISS-II data offers a significant improvement in spatial resolution as compared to the Landsat MSS. A set of computer programmes developed for analysis of lineaments were used to study the parameters such as lineament frequency, length and density in order to quantify the added information derived using IRS-1A LISS-II images. The incremental contribution of LISS-II images are of the order of 100 per cent for lineament frequency and about 60 per cent for total line kilometers of lineaments detected.  相似文献   

16.
A systematic statistical analysis of the lineament fabric data associated with the Great Boundary Fault of Rajasthan provides 26 axes of high density girdles. Further statistical treatment of these isolated axes following the methods of analysis of directional data indicates that the lineament can be classified into genetic categories. The result indicates that the Great Boundary Fault and the Chambal Fault are genetically related and that the majority of the lineaments are the result of the reactivation of the Great Boundary Fault under a southward directed dominant stress field.  相似文献   

17.
The authors interpreted a major lineament in Ladakh region on LANDSAT imagery and named it Nubra-Gartang superlineament, after the two livers along which it is aligned for a considerable distance. The superlineament trending NW-SE, extends for a distance of 750 km from the Afganistan border to southern Tibet. Structural and geomorphic evidences indicate that the lineament is perhaps still active and represents a dextral strike-slip fault. The fracture pattern and other tectonic elements suggest that a ‘suture’ zone is expected further to the north of this line in the Pamir region and the so called ‘Indus suture zone’ may be only a sister fracture to this superlineament. Occurrences of Quaternary volcanics along the superlineament are not ruled out and as such the zone offers a favourable locale for associated mineralisation.  相似文献   

18.
Geological mapping of the Vindhyan and Deccan Trap terrain around Jhalawar was accomplished by aerial photointerpretation with limited field checks in parts, by conventional field mapping for part of the area and also by interpretation of LANDSAT imagery. A comparative assessment of the data producing capability and accuracy of these methods is made from the case study. Major geological formations comprising Semri, Kaimur, Rewa and Bhander groups of Vindhyan supergroup, Deccan Trap and recent fluvial sediments are equally interpretable from all three level (i.e. ground, air and space) surveillance data. All the members and units are mappable on air photos and on ground but not on the LANSAT imagery. It is difficult to plot all the flows and flow units of Deccan Trap on a topographic base map during conventional field mapping but these are more or less separable on aerial photos. Structural trends are decipherable by photointerpretation but lineaments are well depicted on LANDSAT imagery. Physical and petrological characters of rocks can, however, only be studied in situ and by laboratory analysis of samples. Aerial photointerpretation techniques can be applied for geological mapping of Vindhyan and Deccan Trap terrain with high degree of confidence and reasonable accurate maps can be generated. LANDSAT imagery are useful for generation of small scale reconnalssance and lineament pattern maps. The best system of mapping such terrain would be photointerpretation with limited field check and collection of essential groundtruth and specimens for laboratory analysis along selected traverses thus minimising the time and cost of survey.  相似文献   

19.
Fortran 77 programs have been developed for summarisation of lineament pattern and fracture traces on MS-DOS based micro-computer system. Two menu driven programmes CLAFY and HIST perform the above task. CLAFY reads the X, Y co-ordinates of lineament and points from an input file and produces an output file containing azimuth frequency, total length and average length for 18 predefined azimuth classes at 10 degree interval. HIST reads the output generated by CLAFY and offers an option to generate histograms of azimuth frequency/total length/average length on a dot matric printer. CLAFY and HIST were tested using digitised lineament co-ordinates derived from lineament maps of parts of Central Kerala region, southwestern, India which were prepared based on Landsat imagery interpretation. The programmes afford repetitive manipulation of large quantities of lineament data without ignoring short and /or faint lineaments which have geologic significance.  相似文献   

20.
The study area comprises Bundelkhand Granite of Archaean age in the east, unconformably overlain by Upper Vindhyan sequence, ranging from Upper Kaimur Sandstone to Lower Bhander Sandstone Groups, in the west. Geomorphologically, the area has been divided into three geomorphic provinces viz. (1) Bundelkhand inselberg — pediplain, (2) Vindhyan structural plateau, consisting of two major sub-levels of Upper and Lower Bhander Sandstone Groups and two minor sub-levels of Upper and Lower Rewa Sandstone Groups, separated by escarpment and/or valleys, and (3) Chambal alluvial plain. Photo-interpretation and field studies indicate that there are three sets of lineament trends in the area out of which the NNW-SSE trend comes out very strongly on imagery and is correlatable with basement fracture trend of Bundelkhand massif. The synoptic view through imagery also gives the impression that the course of Chambal river towards north and west is controlled by a major lineament, possibly a regional fault trending NE-SW. The NNW-SSE lineament trend mentioned above then probably reflects tension release aspect of the faulting. The field check has brought out some very broad, gentle warps also with NNE-SSW trend in the area. The paper presents the salient observations on geological, structural and geomorphological studies for Shivpuri area based on remote-sensing techniques and their utility for such regional investigations.  相似文献   

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