scholarly journals Automatic Extraction and Geospatial Analysis of Lineaments and their Tectonic Significance in South Cameroon Area using Remote Sensing Techniques and GIS

2020 ◽  
Vol 43 (4) ◽  
Author(s):  
Yves Shandini ◽  
Marcelin Pemi Mouzong ◽  
Raphael Onguene ◽  
Minette Eyango Tomedi ◽  
Jacques Etame ◽  
...  
Keyword(s):  
Tectonic Stress ◽  
Landsat 8 ◽  
Tectonic Structures ◽  
Density Distributions ◽  
Tectonic Events ◽  
Pan African ◽  
Tectonic Significance ◽  
Crustal Structures ◽  
Remote Sensing Techniques ◽  
The Relationship

This study investigates the dominant orientations of lineament features and the relationship between these trends and the spatial orientation of tectonic structures in the transition zone of the Congo craton and the Pan African belt in South Cameroon area. Landsat 8 OLI/TIRS and hill-shaded images, constructed from 30 m-resolution SRTM-DEM data, were used for automatically extracting and mapping geological lineaments. Lineament features were analyzed by means of azimuth frequency and length density distributions. Three major sets of lineaments trending W–E, ENE-WSW and WNW-ESE are identified in the South Cameroon area. These trends are probably related to repeated reactivation of pre-existing crustal structures during Eburnean and Pan-African tectonic episodes. The lineaments were formed under the compressional tectonic stress regimes generated during these tectonic events.

scholarly journals Water stress coefficient determined by orbital remote sensing techniques

2020 ◽  
Vol 24 (12) ◽  
pp. 847-853
Author(s):  
Élvis da S. Alves ◽  
Roberto Filgueiras ◽  
Lineu N. Rodrigues ◽  
Fernando F. da Cunha ◽  
Catariny C. Aleman
Keyword(s):  
Remote Sensing ◽  
Water Stress ◽  
Irrigation Management ◽  
Simple Algorithm ◽  
Landsat 8 ◽  
Stress Coefficient ◽  
Use Efficiency ◽  
Remote Sensing Techniques ◽  
Water Stress Coefficient ◽  
The Relationship

ABSTRACT In regions where the irrigated area is increasing and water availability is reduced, such as the West of the Bahia state, Brazil, the use of techniques that contribute to improving water use efficiency is paramount. One of the ways to improve irrigation is by improving the calculation of actual evapotranspiration (ETa), which among other factors is influenced by soil drying, so it is important to understand this relationship, which is usually accounted for in irrigation management models through the water stress coefficient (Ks). This study aimed to estimate the water stress coefficient (Ks) through information obtained via remote sensing, combined with field data. For this, a study was carried out in the municipality of São Desidério, an area located in western Bahia, using images of the Landsat-8 satellite. Ks was calculated by the relationship between crop evapotranspiration and ETa, calculated by the Simple Algorithm for Evapotranspiration Retrieving (SAFER). The Ks estimated by remote sensing showed, for the development and medium stages, average errors on the order of 5.50%. In the final stage of maize development, the errors obtained were of 23.2%.

scholarly journals ASSESSMENT OF RELATIONSHIP BETWEEN LAND SURFACE TEMPERATURE AND NORMALIZED DIFFERENT VEGETATION INDEX USING LANDSAT IMAGES IN SOME REGIONS OF DIYALA GOVERNORATE

2021 ◽  
Vol 52 (4) ◽  
pp. 793-801
Author(s):  
Al-Jbouri & Al-Timimi
Keyword(s):  
Surface Temperature ◽  
Land Surface Temperature ◽  
Land Surface ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Climatic Conditions ◽  
Landsat 8 ◽  
Landsat Images ◽  
Remote Sensing Techniques ◽  
The Relationship

Agriculture is the most important and most dependent economic activity and influenced by climatic conditions as the climate elements represented by solar radiation, temperature, wind and relative humidity. Therefore, is necessary that analyze and understand the relationship between climate and agriculture. The aim of this study to assessment the relationship between land surface temperature (LST) and normalized difference vegetation index (NDVI) for three regions of Diyala Governorate in Iraq (Al Muqdadya, Baladrooz, and Baquba) by through using of remote sensing techniques and geographic information system (GIS).The Normalized difference vegetation index NDVI and land surface temperature (LST) were used in two of the Landsat-5 ETM + and Landsat-8 OLI satellite imagery during the years 1999 and 2019.  The results showed that increased in NDVI and decreased in LST for 2019, while for 1999 increased in LST and decreased in NDVI for the three regions. Finally, the regression was used to obtain that correlation between LST and NDVI. It was concluded that the correlation coefficient between NDVI and LST is negative, where the strongest correlation was 0.76 for Baquba and weakest correlation was 0.55 for Muqdadyia.

scholarly journals WATER SALINITY MAPPING OF KARUN BASIN LOCATED IN IRAN USING THE SVR METHOD

2019 ◽  
Vol XLII-4/W18 ◽  
pp. 97-101
Author(s):  
M. Ansari ◽  
M. Akhoondzadeh
Keyword(s):  
Water Salinity ◽  
Spectral Signature ◽  
Support Vector ◽  
Landsat 8 ◽  
Complex Issue ◽  
Karun River ◽  
Remote Sensing Techniques ◽  
The Relationship

Abstract. Water salinity is a complex issue in coastal and estuarine areas. Currently, remote sensing techniques have been widely used to monitor water quality changes, ranging from river to oceans. The salinity of Karun River has been increasing due to some critical factors, therefore, This study aimed at building regression models to ascertain the water salinity through the relationship between the reflectance of the Landsat-8 OLI and In situ measurements. A total of 102 observed samples were divided into 70% training and 30% test from June 2013 to July 2018 along the Karun River. Spectral signature analysis showed that band 1 - Coastal/Aerosol (0.433–0.453 μm), band 2 - Blue (0.450–0.515 μm) and band 3 - Green (0.525–0.600 μm) are sensitive to salinity . Furthermore, to have a comprehensive investigation, the Support Vector Regression (SVR) method was applied. The outcomes related to the quality of the SVR depend on several factors e.g. proper setting of the SVR meta-parameters, therefore, to deal with this issue Genetic Algorithm (GA) was applied. The SVR model resulted in values of R2 and RMSE for test data which are respectively obtained to be 0.7 and 390 μs cm−1. Eventually, Karun water salinity maps were prepared by SVR method to demonstrate the Karun water salinity on 1 February 2015 and 5 September 2018.

scholarly journals Evaluation of the Consistency of Simultaneously Acquired Sentinel-2 and Landsat 8 Imagery on Plastic Covered Greenhouses

2020 ◽  
Vol 12 (12) ◽  
pp. 2015 ◽  
Author(s):  
Manuel Ángel Aguilar ◽  
Rafael Jiménez-Lao ◽  
Abderrahim Nemmaoui ◽  
Fernando José Aguilar ◽  
Dilek Koc-San ◽  
...  
Keyword(s):  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Coefficient Of Determination ◽  
Landsat 8 ◽  
Surface Reflectance ◽  
Remote Sensing Techniques ◽  
Image Pairs ◽  
Study Sites ◽  
High Level ◽  
Sentinel 2

Remote sensing techniques based on medium resolution satellite imagery are being widely applied for mapping plastic covered greenhouses (PCG). This article aims at testing the spectral consistency of surface reflectance values of Sentinel-2 MSI (S2 L2A) and Landsat 8 OLI (L8 L2 and the pansharpened and atmospherically corrected product from L1T product; L8 PANSH) data in PCG areas located in Spain, Morocco, Italy and Turkey. The six corresponding bands of S2 and L8, together with the normalized difference vegetation index (NDVI), were generated through an OBIA approach for each PCG study site. The coefficient of determination (r2) and the root mean square error (RMSE) were computed in sixteen cloud-free simultaneously acquired image pairs from the four study sites to evaluate the coherence between the two sensors. It was found that the S2 and L8 correlation (r2 > 0.840, RMSE < 9.917%) was quite good in most bands and NDVI. However, the correlation of the two sensors fluctuated between study sites, showing occasional sun glint effects on PCG roofs related to the sensor orbit and sun position. Moreover, higher surface reflectance discrepancies between L8 L2 and L8 PANSH data, mainly in the visible bands, were always observed in areas with high-level aerosol values derived from the aerosol quality band included in the L8 L2 product (SR aerosol). In this way, the consistency between L8 PANSH and S2 L2A was improved mainly in high-level aerosol areas according to the SR aerosol band.

A Phenomenological Theory of Socioeconomic Systems with Spatial Interactions

1982 ◽  
Vol 14 (7) ◽  
pp. 869-888 ◽  
Author(s):  
P F Lesse
Keyword(s):  
Lagrange Multipliers ◽  
Average Cost ◽  
Phenomenological Theory ◽  
Traffic Flows ◽  
Spatial Interactions ◽  
Practical Application ◽  
Density Distributions ◽  
Expected Values ◽  
Probability Density Distributions ◽  
The Relationship

This paper deals with a class of models which describe spatial interactions and are based on Jaynes's principle. The variables entering these models can be partitioned in four groups: (a) probability density distributions (for example, relative traffic flows), (b) expected values (average cost of travel), (c) their duals (Lagrange multipliers, traffic impedance coefficient), and (d) operators transforming probabilities into expected values. The paper presents several dual formulations replacing the problem of maximizing entropy in terms of the group of variables (a) by equivalent extreme problems involving groups (b)-(d). These problems form the basis of a phenomenological theory. The theory makes it possible to derive useful relationships among groups (b) and (c). There are two topics discussed: (1) practical application of the theory (with examples), (2) the relationship between socioeconomic modelling and statistical mechanics.

Tectono-magmatic reactivation of Téfidet Cretaceous trough during Cenozoic (Aïr, Niger)

2016 ◽  
Vol 187 (2) ◽  
pp. 73-82 ◽  
Author(s):  
Yacouba Ahmed ◽  
Moussa Konaté ◽  
Moussa Harouna
Keyword(s):  
Volcanic Activity ◽  
Upper Jurassic ◽  
South Atlantic ◽  
The South ◽  
Lake Chad ◽  
Pan African ◽  
The Relationship ◽  
Extension Period

AbstractThe Téfidet trough (eastern Niger) belongs to the Ténéré megasystem set of Cretaceous rifts N130°E to N170°E oriented, corresponding to the direction of the Lake Chad-Hoggar tectonic axis.The study of the relationship between the structure of the trough and alkaline fissural volcanism that developed there from the Oligocene to Plio-Quaternary shows the uniqueness of the Téfidet trough compared to the neighboring contemporary volcanic areas of Hoggar, Cameroon, and southern Aïr.The tectono-magmatic reactivation of the Cretaceous Téfidet trough developed in two steps: – a period contemporaneous with the Tuareg shield bulging (Aïr, Hoggar, Iforas);– a subsequent extension period generally N060°E, which has persisted since the opening of the South Atlantic (upper Jurassic to Plio-Quaternary).The fissural volcanism, due to the reactivation of Pan African and Cretaceous faults evolved concomitantly with the N060°E extension (syn-magmatic micro-fractures with basaltic filling), in several steps, from Oligocene to Plio-Quaternary.This study highlights the existence of periods of quietness and recovery of volcanic activity, for which two assumptions can be made: – no enough absolute datings,– apolyphased extension of the rift.The latter hypothesis seems to be supported by three periods of volcanic quietness, 28–24 m.y., 20–14 m.y. and 8–5 m.y., observed in the northern and the southern Aïr, Gréboun and Todgha, respectively.

scholarly journals Lineament automatic extraction analysis for Galal Badra river basin using Landsat 8 satellite image

2019 ◽  
Vol 12 (25) ◽  
pp. 44-55 ◽  
Author(s):  
Safaa Sabah Adhab
Keyword(s):  
Program Analysis ◽  
Satellite Image ◽  
Landsat 8 ◽  
Automatic Extraction ◽  
Lineament Density ◽  
Density Analysis ◽  
Lineament Analysis ◽  
Intersection Density ◽  
Surrounding Areas ◽  
The Relationship

This research including lineament automated extraction by using PCI Geomatica program, depending on satellite image and lineament analysis by using GIS program. Analysis included density analysis, length density analysis and intersection density analysis. When calculate the slope map for the study area, found the relationship between the slope and lineament density.The lineament density increases in the regions that have high values for the slope, show that lineament play an important role in the classification process as it isolates the class for the other were observed in Iranian territory, clearly, also show that one of the lineament hit shoulders of Galal Badra dam and the surrounding areas dam. So should take into consideration the lineaments because its plays an important role in the study area.

Brittle deformation effects on the geothermal area framework, in Southern Tuscany, by multiscale lineament domain analysis

2021 ◽  
Author(s):  
Federico Rabuffi ◽  
Massimo Musacchio ◽  
Francesco Salvini ◽  
Malvina Silvestri ◽  
Maria Fabrizia Buongiorno
Keyword(s):  
Remote Sensing ◽  
Domain Analysis ◽  
Multiscale Approach ◽  
Geothermal Area ◽  
Brittle Deformation ◽  
Tectonic Structures ◽  
Structural Framework ◽  
Ophiolitic Rocks ◽  
The Relationship

&lt;p&gt;Remote Sensing is a proven tool to study the Earth's surface and allows to analyze the wide portion of the surfaces by using different platforms/sensors (e.g. optical and active remote sensing, lidar), giving the possibility of multidisciplinary and multiscale approaches. In the proposed study, remote sensing analysis provides the possibility to understand the relationship between tectonic structures, lithology, and geothermal manifestations, and to test these techniques to monitor geothermal areas. This study allowed us to better understand the structural framework of a geothermal area, located in Southern Tuscany, highlighting the role of brittle deformation to produce an enhanced pathway for fluid migrations and upwelling.&lt;/p&gt;&lt;p&gt;The studied area is the &amp;#8220;Parco Naturalistico delle Biancane&amp;#8221; (PNB) in the Grosseto province and belongs to the Cenozoic Tyrrhenian-Apennine orogenic system. The tectonic framework includes a fault and thrust belt setting derived from the collision between the Corsica-Sardinia Block and Adriatic Plate during late Oligocene-Miocene times. This process determined the pile-up of several tectonic units which are, from the top: (1) Ligurian Units consisting of ophiolitic rocks and pelagic sediments (Jurassic - Oligocen); (2) Cretaceous-Oligocene terrigenous deposits; (3) The Mesozoic Tuscan Nappe. Successively, the belt was affected by a regional, mainly extensional tectonics, then a magmatic intrusion affected this thinned Tyrrhenian belt to form the Tuscan Magmatic Province. In Recent time, the region underwent a general, yet differentiated uplift, and the major geothermal areas locate to the relative higher zone. This provides the Southern Tuscany to be the main Italian geothermal area.&lt;/p&gt;&lt;p&gt;In this study, we analyzed the area from several points of view. The lineament domain analysis was performed in a multiscale approach: from 90 meters to 5 meters of pixel size, including 30 m and 10 m. This multiscale analysis allowed the identification of a number of lineament clusters related to the different tectonic phases which affected the PNB area. The found lineament distribution (in terms of azimuth and length) reflects the geodynamics effects on the surface, their clustering was related to the various crustal stress trajectories both at the regional and local scales.&lt;/p&gt;

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