Lineament Intersection Density Research Articles

Zonation of Landslide Hazards Based on Frequency Ratio Modeling at Coonoor and Kothagiri Taluks of Nilgiri District, Tamil Nadu, India

A frequency ratio model is developed within the framework of a Geographic Information System (GIS) to map landslide hazards in a mountainous environment. The Nilgiri Hills (Mountains) of Tamil Nadu are prone to landslides; these landslides are typically the result of the structural failure of thick laterite soils that have been saturated by heavy rains during the monsoon season. The GIS based analysis in the present work incorporates the frequency ratio values from the existing landslides. The landslide inventory of paleoscars was located by a collection of existing historical reports. Detailed field surveys have been carried out in the study area. In the observation, 118 landslide locations were identified and mapped by GIS; out of that, 83 (70 %) locations were randomly selected for the training data set and the remaining 35 (30 %) cases were used for the model validation purposes. For spatial modeling, the landslide triggering parameters include active-passive slope, concave-plain-convex slope, drainage density, dissected-undissected slope, geology, geomorphology, lineament density, lineament frequency, lineament intersection density, land use / land cover, rainfall, regolith cover, shallow-moderate-steep slope, soil and water level for landslide hazard zonation. This model has been used to spatially classify the study area into three zones viz; high, moderate and low landslide hazard zones. The frequency ratio model was validated with the existing landslide location data using R-index method. The validation of the results showed that the values is 1115.23 in R-index as high hazard zone when R-index increases with the level of susceptibility. The obtained results will provide a basis for planning, risk reduction strategies and various developmental activities in the Nilgiri area.

Analysis and Interpretation of Lineaments for Evaluation of Groundwater Potential in Shendam and Environs, North Central Nigeria

This study was done to evaluate the groundwater potentials of Shendam and environs using lineaments analysis. The trends of field joints were measured during mapping and using satellite remote sensing to generate lineament. The area is underlain by crystalline basement rocks of biotite granite, medium grain granite, and syenite. Assessment was carried out to depict the possibility of groundwater occurrence in the area. LANDSAT ETM+ imagery was used, together with the geological map to investigate areas favorable for groundwater development. This was achieved by plotting the lineament trends, superimposing the lineament on the geological map, superimposing the lineament on the drainage map, furthermore by plotting density map to know the groundwater potentials of the area. Lineament was used in drawing the respective rose diagrams for each rock type. Structurally, the area is characterized by a predominant NE to SW trend which also affects or controls drainage and groundwater occurrence with major groundwater recharge areas trending NE- SW of the study area. Analyses have shown that the study area has numerous fractures whose major trends are mainly in NE-SW directions. Lineament density maps shows the cross-cutting lineaments to be relatively high in the areas around the northeastern to southwestern parts of the study area but low in the other areas. Zones of high lineament intersection density are feasible zones for groundwater prospecting.

Application of remote sensing, GIS and geophysical techniques for groundwater potential development in the crystalline basement complex of Ondo State, Southwestern Nigeria

Remotely sensed and electrical resistivity data were employed to develop the groundwater potential of the hard-rock terrain of Ondo State, Southwestern Nigeria. Administrative map, Landsat ETM +, Aster DEM were acquired and processed to produce geomorphological map, lineament and lineament-intersection density maps. Electric sounding and groundwater yield data were also acquired. The electric sounding data were interpreted quantitatively. Aquifer thickness and coefficient of anisotropy were generated from geoelectric parameters (resistivities and thicknesses) deduced from the interpreted results of the electric sounding data. All these maps were reclassified into hydro-thematic maps and combined using weighted linear combination function in ArcGIS 10.5 software to develop a composite groundwater potential map. Groundwater yield data were used to establish the reliability of the groundwater potential map derived from the remotely sensed and geophysical data interpretation. Erosional and depositional landforms were identified in the area and these included: residual hill (677–980 m.a.s.l), pediment (452–677 m.a.s.l), pediplain (226–452 m.a.s.l) and pediplain with alluvium (74–226 m.a.s.l). The lineament density ranged from 0.00 to 69.48 km/km2. The lineament-intersection density ranged between 0.00 and 72.92 km/km2. The aquifer thicknesses varied from 0.2 to 79 m. The aquifer types identified from the study were the weathered layer (WL), weathered/fractured (unconfined) (W/F(u)), weathered/fractures (confined) (W/F(c)), weathered/fractured (unconfined)/fractured (confined) (W/F(u)/F(c)) and fractured confined aquifer (F(c)). The coefficient of anisotropy (coa) values ranged from 1.0 to 2.88 units. Four distinct groundwater potential zones: very low, low, moderate and high zones were identified. However, the study concluded that the groundwater potential rating of the study area was low to moderate.

GIS Based Index Overlay Method in Targeting Heavy Mineral Deposits, Southern Kerala Coast, India

Owing to the strategic importance in defence and the other industrial applications, the heavy minerals have attracted the attention of the geoscientists since long time. But they have been using mostly the traditional techniques for a long time for targeting the heavy mineral deposits. Later, the scientists have started employing modern techniques like scintillometer based field surveys, remote sensing and the laboratory based sedimentological and heavy mineral studies. But since the traditional techniques are more cumbersome and would be very difficult to cover the vast length of the Indian coasts of over 7500 km, faster and effective techniques are necessary. So, the information value method was accomplished in the present study to demonstrate the targeting of heavy minerals in parts of Kerala extending from 76° 41' - 08° 53' in NNW and 77° 13' - 08° 17' in SSE (1,811sqkm). In this study five geosystem maps, viz; Lithology, Lineament Frequency, Lineament Density, Lineament Intersection density and Geomorphology were prepared using the raw and digitally processed LANDSAT ETM 7 and IRS LISS IV FCC data sets. These geosystem maps were firstly prepared as vector GIS layers and then converted into raster maps using ARC GIS software with the pixel size of 100sq.m and the total pixels of 1,64,358. On the basis of the contribution of the above five main geosystem variables towards the heavy mineral potentials, weightages were assigned (Wi) to each of them. Similarly, depending upon the heavy mineral possibilities of the sub variables of the above five main geosystem variables, scores were assigned (Si) to each sub variables of the 5 main geosystem variables. Then, the Wi values were multiplied with the corresponding Si values of each of the sub variables of the 5 main geosystem variables and those were considered as final weightages (HMP-Heavy Mineral potentials) and assigned the same to the corresponding pixels of each sub variables of the five main variables. Followingly, the each WiSi weighted values of the 1,64,358 pixels of the lithology main geosystem variable were added with corresponding pixels of the remaining 4 main geosystem variables using ADD function menu of ARC GIS and integrated raster GIS database was generated with all the 1,64,358pixels having the cumulative WiSi values (ΣWiSi). Then, on the dynamic range of the ΣWiSi values, these pixels were classified into Very High, High, Moderate, Low and Very Low zones of heavy mineral concentrations. This was validated with heavy mineral weight percentage data derived from the field samples collected from the study area during survey. This study was basically undertaken to replicate it for the rapid appraisals of the probable heavy mineral target areas along the Indian coasts. However this can be replicated anywhere.

The Application of Geologic Lineament Extracted From Dual-Orbit SAR Images for Fluid Flow Path Detection and Characterization in Geothermal System

The limited nature of subsurface imaging data in geothermal field makes surface data important to infer subsurface geologic conditions. One of the main geologic features that can be extracted from surface data is lineament which can be attributed to rock fractures, including joints and deep-seated faults. Fractures play a dominant role in the creation of porosity and permeability that allows the storage and flow of thermal fluid in geothermal reservoirs. Therefore, it is important to characterize rock fractures and model the flow of thermal fluid through them to better understand the geothermal reservoir. This study evaluates the application of lineaments extracted from dual-orbit Synthetic Aperture Radar (SAR) images acquired by the Phased-L Synthetic Aperture Radar (PALSAR) sensor on the Advanced Land Observing Satellite (ALOS) as input for fracture modeling to reservoir simulation in geothermal field. The SAR images were acquired from the Geureudong area in Aceh. Lineaments were extracted automatically from SAR images using modified Segment Tracing Algorithm (mSTA). Noise filtering and edge enhancement algorithms were applied to the SAR images prior to mSTA to optimize the extraction of geologically significant lineaments. The extracted lineaments were spatially analyzed, including lineament frequency density, lineament length density, lineament intersection density, and lineament direction rose diagram. Representative fracture model with a vertical dip angle was created from the extracted lineaments and was assigned with reservoir properties, including permeability and porosity. Thermal fluid flow was simulated through it to detect flow path and to characterize fluid flow in a geothermal system. Spatial analysis of the extracted lineaments showed a good correlation with the trend of geological structures observed in the field. The simulated fluid flow path showed good agreement with the spatial distribution of geothermal manifestations. Simulation results showed a strong correlation between fluid flow characteristics to the orientation, density, and connectivity of the fracture model.

Spatial assessment of termites interaction with groundwater potential conditioning parameters in Keffi, Nigeria

Termite mounds are traditionally presumed to be good indicators of groundwater in places they inhabit but this hypothesis is yet to be scientifically substantiated. To confirm this assertion, it is expected that termite mounds would have strong correlations with groundwater conditioning parameters (GCPs). In this study, termite mounds distribution covering an area of about 156 km2 were mapped and their structural characteristics documented with the aim of examining their relationships with twelve (12) chosen GCPs. Other specific objectives were to identify specific mound types with affinity to groundwater and to produce a groundwater potential map of the study area. To achieve this, 12 GCPs including geology, drainage density, lineament density, lineament intersection density, land use/land cover, topographic wetness index (TWI), normalized difference vegetation index (NDVI), slope, elevation, plan curvature, static water level and groundwater level fluctuation were extracted from relevant sources. Frequency ratio (FR) and Spearman’s rank correlation were used to find relationships and direction of such relationships. The result revealed a consistent agreement between FR and Spearman’s rank correlation that tall (≥1.8 m) and Cathedral designed mounds are good indicators of groundwater. Further, the groundwater potential map produced from the Random Forest (RF) model via Correlation-based Feature Selection (CFS) using best-first algorithm depicted an erratic nature of groundwater distribution in the study area. This was then classified using natural break into very-high, high, moderate, low and very low potential classes and area under curve (AUC) of the receiver operating characteristics (ROC) showed an 86.5% validity of the model. About 75% of mapped termite mounds fell within the very-high to moderate potential classes thereby suggesting that although tall and cathedral mounds in particular showed good correlations with a number of GCPs, high mound density in a locality is also an indication of good groundwater potential.

Fuzzy logic approach for landslide hazard zonation mapping using GIS: a case study of Nilgiris

Landslides are one of the common natural as well as man-made hazards in mountainous terrain which causes huge damage to human beings and property. In this paper mapping of landslide hazardous zones based on fuzzy logic approach using GIS techniques. In this regard various landslide parameters were generated which related to landslide occurrences in Coonoor and Kothagiri taluks. The fuzzy membership value is assigned on individual parameters such as active–passive slope, concave-plain-convex slope, drainage density, dissected-un dissected slope, geology, geomorphology, lineament density, lineament frequency, lineament intersection density, landuse/land cover, rainfall, degree of weathering /regolith cover, shallow-moderate-steep slope, soil, and water level. An attempt is made to integrate these parameters on different fuzzy operators and produce landslide hazard zonation map and its divides the study area into three zones viz., high, moderate and low. 95% of the existing landslides have been observed in high hazard class. The final map is validated using area under curve method for calculating prediction accuracy.

English

This research investigates groundwater potential of Ibodi and its environs using satellite imagery remotely sensed and aeromagnetic dataset. This hydrogeological investigation involved the extraction of lineaments from Landsat Thematic Mapper (TM) satellite imagery and aeromagnetic lineament of the area. The processed image revealed lineaments trending in approximately NE-SW direction; also, Landsat and aeromagnetic lineament trends tend to agree in the study area, suggesting real continuous fractures at depth. Hydrogeological maps, based on lineament and lineament intersection were produced from the generalized lineament trends in the area. The lineament intersection density map identified cluster zones in the range of 0 to 1.17, 1.17 to 2.34, 2.34 to 3.52, 3.52 to 4.69 and 4.69 to 5.86 kg/kg2, respectively. The map showed that the concentrations of lineament intersection nodes dominate the eastern and north-eastern parts of the study area while other areas are characterized by scanty or no lineament intersections nodes. The lineament analysis has been effectively done in a geographic information system (GIS) environment. Results from the vertical electrical sounding (VES) data reveals that the areas where the lineament intersected has tendency of very high groundwater prospect which reflects that the area will be good for groundwater development. The study thus displays that the remote sensing and aeromagnetic technique is capable of extracting lineament trends in an inaccessible tropical forest and has led to the delineation of areas where groundwater occurrences are most promising for sustainable supply. Key words: Geology, landsat lineaments, aeromagnetic lineaments, lineament intersections, geographic information system (GIS).

Application of satellite remote sensing to groundwater potential modeling in Ejigbo area, Southwestern Nigeria

Landsat-7 EMT+ and ASTER GDEM images of Ejigbo area, Osun State Nigeria were processed to generate composite lineament map and lineament-intersection map. Thirty-two Schlumberger vertical electrical sounding (VES) data set were quantitatively interpreted to determine aquifer resistivities and aquifer thicknesses in the area. The lineament density ranged between 0 and 5.52 km/km2. Thematic maps of the geology, the lineament density, the lineament-intersection density, the aquifer thickness and the aquifer resistivity of the study area were integrated to classify the area into varied groundwater potential zones. The study concluded that the groundwater potential of areas around Ejigbo, Osun state is of poor to moderate level rating.

Application of GIS-Based Evidential Belief Function Model to Regional Groundwater Recharge Potential Zones Mapping in Hardrock Geologic Terrain

The evidential belief function – Dempster-Shafer theory (EBF-DST) model was applied and validated for groundwater recharge potential zoning in the hard-rock geologic terrain, southwestern Nigeria, using geographic information systems (GIS). Data about related factors, including satellite imagery, climate and geology were collected and input into a spatial database. In addition, groundwater well yield data inventory of the area were collected from 78 well locations. The groundwater well yield data were partitioned into two data sets, using partitioning criterion ratio of 70 to 30 for training and validation of the model. By using the constructed spatial database, six groundwater recharge conditioning factors such as slope, drainage density, lineament density, lineament intersection density, lithology and rainfall were extracted. The relationships between the well locations and the factors were identified and quantified by using the EBF-DST model. Four belief function series were calculated: belief (Bel), disbelief (Dis), uncertainty (Unc), and plausibility (Pls). The integrated belief function was used to produce the groundwater recharge potential prediction index (GRPPI) map. Furthermore, to compare the performance of the EBF-DST result, multi-criteria decision analysis - analytic hierarchy process (MCDA-AHP) model was applied. The success-rate and prediction-rate curves were computed to estimate the efficiency of the proposed EBF-DST model compared to the MCDA-AHP model. The validation results demonstrated that the success-rate for EBF-DST and MCDA-AHP models were 89 and 82 %, respectively. The area under the curve (AUC) of prediction-rate for both EBF-DST and MCDA-AHP models were calculated as 89 and 78 %, respectively. The outputs accomplished from the current research proved the efficacy of EBF-DST model in groundwater recharge potential zones mapping.

Study of Groundwater Prospects of the Crystalline Rocks in Purulia District, West Bengal, India Using Remote Sensing Data

Visual interpretation of satellite imageries of IRS P6 LISS III standard false colour composite (FCC) has been made for lineament and hydrogeomorphological analyses. Analyses of lineament density, lineament intersection density, spatial dis- tribution of hydrogeomorphic units and lithology have been carried out for the study of groundwater prospects in crystalline rocks. Each theme is assigned a weightage depending on its influence on the storage and movement of groundwater and each unit in every theme map is assigned a knowledge based ranking depending on its significance to groundwater occurrence. The cu- mulative scores have been worked out and the scored pattern has been contoured in preparing the final potential map using Surfer software and classified into five groundwater prospect categories which are further justified by hydrological studies.

The relationship between lineaments and borehole yield in North West Province, South Africa: results from geophysical studies

Airborne magnetic data and Landsat imagery, as well as time-domain electromagnetic soundings, were used to assess groundwater potential of the region around the town of Mafikeng in North West Province, South Africa. Lineaments were extracted based on on-screen digital data derived from magnetic and Landsat 7 imagery. The relationship between lineament-intersection density and borehole yield was assessed using statistical analysis. The results were discussed with respect to factors that determine the groundwater potential of the area. Correlation between lineament-intersection frequency and borehole yield is 60–65% in the south and southeastern parts, and 45–50% within 5–30 km radius of Mafikeng. The eastern and western parts of the study area are characterized by weak or no correlation. Areas that correspond to high correlation between lineament-intersection frequency and borehole yield suggest the significance of cross-cutting structures in controlling groundwater potential zones, while results that suggest low or no correlation represent the influence of other factors. The overall results demonstrate that the combined analysis of airborne magnetic data, satellite imagery, borehole yield and ground-based time-domain electromagnetic soundings provide the best approach for groundwater assessment within the hard rock and carbonate terrains of the study area.

Remote Sensing of the Lineament Patterns Associated with the Great Boundary Fault of Rajasthan

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.

Digital analysis of lineaments—A test study on South India

A procedure for analyzing digitized linear features was developed and applied to an area lying within 13–16°N and 74–78°E comprising the greenstone-granite terrain of South India. The digital procedure maps the spatial distribution of lineament length for any orientation interval using a grid cell approach. In addition, lineament intersection density, and cooccurrence of lineaments with specified orientations can be mapped. Several plots were made for the study area indicating the presence of three prominent directional wedges in 310–325°, 40–55°, and 60–75° azimuthal intervals and spatial concentrations of lineament-segments and intersection of lineaments-segments in Dharwar greenstone belts. The spatial plot showing the cooccurrence of lineaments from the prominent directional wedges indicated probable paleostructural signatures. The study demonstrates the utility of developing a spatially georeferenced digital lineament database and applying the associated analytical procedures.