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1.
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   

2.
Synoptivity and the exemplified fracture systems exhibited by the space borne imagery data has helped in solving many of the geological enigma in various parts of the world. The study conducted, using such remotly sensed data, in Jhalawar anticline, part of Proterozoic Cratonic Vindhyan Basin, Rajasthan, India, led to infer the history of tectonic evolution of peribasinal deformation which has been a matter of controversy for a century and more. In Landsat MSS data the Jhalawar region displays a panorama of lineaments and their analysis through azimuthal frequency diagrams, isofracture, lineament incidence and lineament intersection incidence density maps shows that the mean orientation of the lineaments fall in NW-SE and NE-SW and the shape of the various lineament density contours also show NE-SW and NW-SE orientations. In aerial photographs the area exhibits four sets of lineaments in NE-SW, NW-SE, N-S and E-W directions. Amongst these the former two sets are expressed as wide open master fracture systems with prolific vegetation fills along them and the latter two sets are characteristically observed as thin vegetation linears with frequent strike slip faulting along them. The further analysis of these fracture/lineament systems derived from multi-level remote sensing data shows that the Jhalawar anticline, which followed the pattern of flexural slip fold mechanism, was evolved by horizontally disposed σ1 (greatest principal stress) and 3σ (least principal stress) with the former oriented in NE-SW and the latter aligned in NW-SE directions with vertically disposed 2σ. The inference of such palaeostress environment of the Jhalawar region lead in the identification of a buried rigid basement high southwest of Jhalawar anticline, beneath the Deccan pile and loci of ground water, silica sand and probable igneous plug.  相似文献   

3.
Lineament extraction approach allowed mapping of larger number of lineaments in a classical manner in tectonic and structural studies. In the present study, various techniques were adopted to extract lineaments using Landsat ETM+ images. To remove the biasness of the images, some pre-processing techniques like stream ordering, band differencing, colour texturing were employed to enhance the edges of the structural features. Extracted lineaments and its distribution and orientation were mapped using ArcGIS Spatial analyst tool. Results of the study showed maximum number of lineaments were oriented in the ENE–SWS direction with 63° overall inclination. Accuracy assessment and validation were made with respect to visual interpretation and overlaying the lineament on Digital Topographic Model as well as with respect to an existing geological lineament map of the study site. The result of accuracy assessment indicates higher compatibility of Central Indian Suture with the geological map of the study area.  相似文献   

4.
The litho-units of the area between Chawand to Kotra across the Aravalli-Delhi Fold Belt are referable to Bhilwara, Aravalli and and Delhi Supergroups. Earlier workers considered the sequence as progressively younger toward west across the Avavalli Orographic axis. Two-dimensional trend mapping of the planar tectonic anisotropy was carried out to map lineaments from landsat TM Image. Ground checks of the lineament along Chawand-Kotra section suggest that lineaments are tectonic dislocations, morphotectonically controlled by thrusts and ductile shears within the Aravalli-Delhi Fold Belt. The recognition of thrust bounded litho-tectonic units from interpretation of satellite remotely sensed data may necessitate reassessment of the Precambrian lithostraligraphy of the Aravalli and Delhi supergroups in the study area. The paper reports thrust tectonics from Aravalli-Delhi Fold Bell. The Antalia Schuppean Belt is possible duplex; imbricate thrusts are connected with base thrust and continuity with roof thrust has been punctuated by transverse faulting and erosion.  相似文献   

5.
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   

6.
One of the main geological evidence for many ore-bearing deposits and mineralized regions is the existence of points in highly fractured zones and the fragmentation intensity resulted from development of hydrothermal alteration along the fractures, the process leading to the occurrence of ore deposits. In this paper, a new algorithm has been proposed including a set of image processing techniques for detection the lineaments in satellite images by means of programming in MATLAB environment. The set of utilized methods includes line segment extraction by EDLine algorithm, merging line segments by Tavares method and linking the resulting line segments based on the collinearity and proximity criterion. The tectonic structures were stabilized by B-Spline curve fitting. The proposed algorithms were implemented on the ASTER image of a structurally multiple fractured region located in the central Iran, and the lineament map of Venarch area has been depicted. The results obtained from the proposed algorithms indicate a high accuracy of the operations detection of 80% for the reference map lineaments and the overall accuracy of the method is effectively reported as 62%. Combination of the above algorithms proposes a new method that precisely resulted in obtaining image processing of geological evidence for increasing the accuracy and decreasing the risk, before any field operations.  相似文献   

7.
The present work aims to identify, isolate, map and analyse the lineament patterns associated with the Great Boundary Fault (GBF) using remote sensing techniques and to draw some significant conclusions regarding its tectonogenesis therefrom. The locus of the line separating the two distinct patterns of structural trend lines observed on a structural trend map, prepared from the Landsat images, represents the ground disposition of the GBF. The rose diagram plotted for the lineament orientations of different sectors indicates that the whole area was subjected to a similar stress pattern, yet the intensity of stress in each sector was significantly different from the other. The lineament intersection density map clearly demarcates the areas of folding and faulting associated with the GBF. Tectonic anomalies plotted for the area through lineament analysis represent the signatures of prominent surface and sub-surface tectonic elements. The work presents an example for the study of a Precambrian fault system using remote sensing techniques.  相似文献   

8.
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   

9.
Abstract

Photogeological techniques were used to analyze Landsat‐TM images of the Paraiba State, which resulted in the identification of the following structures: lineaments of regional extent, short en echelon lineaments, intricate ramification of the wrench system, and infrastructures among major lineaments and circular or ring structures. This lineament map was correlated to existing geological maps, to areas of known hydrothermal mineralization (Cu, Au, Mo, Ni, W and Ti), and the lineament map was verified in the field reconnaissance. Due to lack of systematic studies of the geology and natural resources of the region the mineral exploration is still in rudimentary stages. The objective of this research is to emphasize the detection and analysis of lineaments, their patterns, and geometry and their relations with the occurrence of mineral resources and its exploration in areas as yet explored. A large number of mineral‐bearing pegmatites of the region are controlled by major lineaments and associated minor lineaments. It is believed that the structures of interest in search for mineral deposits are warping part of the minor shear zones, the intersections of short and regional lineaments, and the circular features.  相似文献   

10.
Of late, airphoto interpretation and Landsat imagery analysis play a vital role in geological mapping for detailed hydrogeological investigations for ground water prospecting. Certain obscure features like lineaments/fracture zones which are masked by surface soil and cultivated lands are easily visible. In hard rocks like granites and basalts the occurrence and movement of ground water are controlled by the fracture pattern. Delineation of potential zones of ground water for successful exploration is possible by the study and analysis of aerial photographs, visual interpretation of Landsat imagery and interactive data analysis system through computer techniques and applications. These techniques constitute for data integration with conventional methods of hydrogeological investigations and exploratory drilling. As a case study an area of 1500 sq km in part of the Narmada river basin of Madhya Pradesh and also forming a portion of Narmada Sagar area covered under topo sheets 46 N/12 and 46 N/16 was taken up. Aerial photographs pertaining to the area of study and Landsat imagery of band 5 and 7 in scale blown upto 1∶250,00 were scanned and analysed. It was observed that the successful artesian wells are located in pominent lineament/fractured zones in the study area. It is also recommended after through analysis different hyddromorphic zonations for future exploration of ground water.  相似文献   

11.
遥感线性体场的数量化分析   总被引：13，自引：0，他引：13  
遥感线性体场是地质构造场和成矿地质场在地球表面和光谱特征上的反映。本文从地质异常场和线性体场的概念出发,利用图像处理技术,较系统地研究了线性体的数据处理方法,建立了线性体场的数量化分析模式:（1）线性体场总体统计特征的计算和图示;（2）线性体场的数字表征;（3）线性体场的数学分析。并以铜陵地区为例,介绍了线性体场的数量化分析方法在地质构造分析和成矿预测中的应用。  相似文献   

12.
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   

13.
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   

14.
Remotely-sensed satellite data of Landsat 5 (TM) and IRS-1A (LISS II) covering parts of central portion of Chotanagapur plateau have been analysed visually to delineate some prominent lineaments in Ranchi district and its adjoining area. One of the most prominent lineament “Ranchi mega lineament? has been analysed in this paper. This lineament is a potential site for base metal mineralisation at some places, and it acts as good groundwater conduit in the region. No earlier attempt to map this entire structural unit as a separate entity is known. Geophysical bouguer gravity anomaly map, lithological and structural maps have some remarkable correlation with this lineament. In the present paper authors have tried to analyse the lineament with respect to its tectonic, mineralisation and groundwater prospects. Resistivity survey carried in close proximity of this lineament at selected sites, indicate that rocks are well fractured at depth. Available lithological and structural map support this lineament as a shear near Purulia (W.B.) and also having base-metal mineralisation potential in this area. Authors opine that existing gravity anomaly map may be further augmented in the light of present study.  相似文献   

15.
The area of upper Vaigai river basin covering parts of Madurai and Theni Districts, in Tamil Nadu, faces acute water scarcity and chronically drought prone. The groundwater resources in the area have not been fully exploited. The present investigation has been made to evaluate the potential zones for groundwater targeting using IRS - ID LISS III geocoded data on 1:50,000 scale. The geology, geomorphology, lineament tectonic maps are generated and integrated to evaluate the hydrogeomorphological characteristics of the upper Vaigai river basin and demarcate the groundwater potential zones. A number of geomorphic units have been observed. Out this the more groundwater prospective units are buried pediment medium, buried pediment deep, flood plain, bajada and lineament and intersection of lineaments. Non potential areas like pediment, pediment inselberg, shallow pediment and pediplain were identified.  相似文献   

16.
利用遥感图像的线性体统计数据进行塔北地区油气勘查十分有效。该区遥感图像上线性体主要以北东向、北西向及近东西向为主,与区域构造线一致。线性体密度异常与局部含油气圈闭空间分布上具有很好的一致性,线性体密度异常区与已知油气田和工业油气井的吻合程度为62.5%.本文主要介绍；①通过线性体统计分析所获得的塔北地区区域构造信息,②通过线性体数据处理获得的线性体密度异常的分布特征和类型；③线性体统计分析在油气勘探方面的应用前景。  相似文献   

17.
Godavari sub-watershed is a part of buried pediplain developed over ‘Chotanagpur’ granite gneiss. Aquifer is unconfined in nature and groundwater occurs under water table condition. In the study area, groundwater is being exploited only through dugwells which are not capable of sustaining long duration pumping. Groundwater exploration involves the investigation of depth and nature of weathered and fractured horizon. To understand the groundwater storage and retrieval in the area, the basement topography derived from Digital Basement Topography Modelling (DBTM), the lineaments identified on remotely sensed data and geohydrological and physiographic data have been analysed. From DBTM, fracture zones have also been inferred. Lineaments (probable fractures) identified with the help of remotely sensed data are linear features representated on a planner surface. Lineaments in the area are subtle in expression due to deeply buried pediplian. Correlation of lineaments with DBTM reveals that a few lineaments/fractures are deep seated and a few have no sub-surface extensions. Also some sub-surface fractures inferred from DBTM have no expressions on the image. Attempt has been made to delineate more authentic lineaments/fractures with the help of remotely sensed data and DBTM. Correlation of probable fractures inferred from remotely sensed data and fracture zones inferred from DBTM indicated that 40 per cent of lineaments seems to be real fractures. Higher correlation may be achieved where lineaments are prominent and reproducible. It has also been observed that those lineaments which correlate with the fracture zones inferred from DBTM, are also not completely traceable in their linear extent. The exaggeration in length of lineaments may be due to subtle nature of lineaments. Correlation shows that remotely sensed lineaments are improtant for groundwater exploration and its authenticity can be further ascertained with DBTM.  相似文献   

18.
The American LANDSAT-I Satellite has acquired Multispectral Scanner Data on four discrete wave-length bands from the green to the near IR spectral regions of almost the entire land area of the world, often repetitively. The territory of Gujarat State and the adjoining region falls on 20 overlapping LANDSAT frames, each of 185 X 185 Kms. Linear features exposed on these individual itnages are many times enhanced when viewed in combination. A number of these lineaments, particularly those with long surficial extent and contrasting expression, reflect the dominat geological trend lines, fracture Systems and tectonic features. An interpretation of the photo format imagery, acquired in late 1972 using Single band as well as additive combination techniques, is presented. An attempt is made to explain the geological signiflcance or lack of it in the case of the dominant lineaments (megalineaments), taking intoconsideration the known geological framework of the area. The methodology for extending such analytical work to areas less known is outlined.  相似文献   

19.
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   

20.
Abstract

Tectonic mapping and geologic evolution of a region were historically conducted on the basis of field observations. After the advent of remote sensing technology, tectonic mapping became much easier and structural mapping through imagery has gained credibility and suitability in regional mapping, tectonic evolution and modeling. In this regard, an attempt has been made to make use of the satellite technology to bring out the structural trends and the fracture/lineament pattern in Biligirirangan region of Northern Tamil Nadu through satellite remote sensing. The folded architecture in Biligirirangan region has evolved from structural trends. The subsurface structures of the region were derived through resistivity contours and resistivity images created by GIS software.

The surficial information derived from the satellite imagery and subsurface structures derived from the resistivity contours and images were integrated with field observations. This integration has given a clear tectonic picture of the Biligirirangan region and the tectonic structures were then analysed for tectonic forces, evolution and modeling.

The study determined that the Structural trends were mostly in a N‐S direction and the folds were of isoclinal type with alternating synclinal and anticlinal folds of an easterly dipping nature. These folds in conjunction with the lineaments have brought out the palaeostress pattern of the Biligirirangan region. The study further suggests that the regional compressive force trending in ENE‐WSW direction was responsible for the present configuration of folds. In addition, the study also focuses the efficacy of the satellite imagery in tectonic analysis and the resistivity contours and images for the subsurface structural analysis.  相似文献   

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