scholarly journals Geomorphic and tectonic implications of the endorheic to exorheic transition of the Ebro River system in northeast Iberia

2018 ◽  
Vol 91 (2) ◽  
pp. 472-492 ◽  
Author(s):  
Ángel Soria-Jáuregui ◽  
Francisco Jiménez-Cantizano ◽  
Loreto Antón
Keyword(s):  
Transient State ◽  
River System ◽  
Asymmetry Factor ◽  
Mature Stage ◽  
Stream Length ◽  
Ebro River ◽  
Iberian Range ◽  
Stage Of Development ◽  
Hypsometric Integral ◽  
Mountain Front

AbstractThe Ebro catchment includes a continental foreland basin that underwent an endorheic–exorheic transition. Morphometric studies, including hypsometric curves, hypsometric integrals, asymmetry factor, mountain front sinuosity, normalised stream-length gradient, and normalised concavity indices for the Ebro River and 32 of its tributaries, show the signals of transient response to this major drainage change. The Ebro River, its upper catchment tributaries, and the Pyrenean tributaries have concave-up longitudinal profiles, concave hypsometric curves, and low hypsometric integrals, parameters typical of deeply dissected basins. This suggests a mature stage of development, controlled by the shift of the base level to the Mediterranean Sea. Iberian Range tributaries display low concavity profiles with numerous knickpoints and high values of hypsometric integral, indicating a transient state as a response to tectonic uplift, ratified by the values of mountain front sinuosity surrounding the basin.

scholarly journals Η επίδραση της γεωλογίας και της τεκτονικής στην εξέλιξη του υδρογραφικού δικτύου και της υδρολογικής λεκάνης του ποταμού Πάμισου της Θεσσαλίας.

2005 ◽  
Vol 38 ◽  
pp. 86
Author(s):  
Κ. ΒΟΥΒΑΛΙΔΗΣ ◽  
Α. ΣΦΕΙΚΟΣ ◽  
Θ. ΠΑΡΑΣΧΟΥ ◽  
Χ. ΚΕΧΑΓΙΑ ◽  
Δ. ΨΩΜΙΑΔΗΣ
Keyword(s):  
Drainage Basin ◽  
River System ◽  
Tectonic Activity ◽  
Mature Stage ◽  
Surface Erosion ◽  
Terrain Analysis ◽  
Entire Study ◽  
Fluvial Terraces ◽  
Stage Of Development ◽  
Hypsometric Integral

River Pamisos is a main tributary of Pinios River, draining the SW part of the Thessaly catchment area. The river's drainage basin comprises part of the plain as well as of the mountainous terrain that bounds the broader Thessaly Plain. In this paper we present the results of both qualitative and quantitative analyses of the drainage network and morphology through processing of digitized data with GIS software. Quantitative measurements allowed objectively to compare different landforms and to calculate less straightforward parameters (geomorphic indices) that may be useful for the identifying particular characteristics of the area, such as the level of tectonic activity and geologic conffiocm the analysis of the hydrographie network values for the D and F parameters were calculated. In addition, terrain analysis resulted in useful conclusions about morphologic indices, derivation of hypsographic curves and integrals for the entire study area. Similarly, the morphological study of fluvial terraces together with that of sub-basins resulted in determination of erosive activity of the river. Finally, the analysis of certain morphometric indices obtained from the hydrographie network and morphology subsequent analyses was used to define the influence of geologic formations and tectonics upon the evolution of the river system. One of the major results of this paper is that the shape of the hypsometric curve and the calculation of the hypsometric integral indicate a mature stage of development for the Pamissos River drainage basin. It is generally known that the landscape in recently developed - active orogens is shaped mainly by two factors, tectonic activity and surface erosion. If we accept that the denudation – erosion rates in Hellenic orogen are approximately the same, then the lack of landmass (indicated by hypsometric integral) should implicate a basin expansion due to tectonic control.

scholarly journals Morphometric analysis and sub-watersheds prioritization of Nagmati River watershed, Kutch District, Gujarat using GIS based approach

2018 ◽  
Vol 39 (1) ◽  
pp. 131-139 ◽  
Author(s):  
Saif Said ◽  
Rabab Siddique ◽  
Mohammad Shakeel
Keyword(s):  
Morphometric Analysis ◽  
Water Conservation ◽  
Mature Stage ◽  
Drainage Pattern ◽  
Stream Network ◽  
Stream Length ◽  
River Watershed ◽  
Stage Of Development ◽  
Sensing Applications ◽  
Hypsometric Integral

AbstractMorphometric analysis of any watershed and its prioritization is one of the important aspects of planning for implementation of management programmes. Present study evaluates the quantitative morphometric characteristics of Nagmati River watershed in Kutch District of Gujarat by utilizing Cartosat-1 data (CartoDEM). In all 19 aerial and 6 linear morphometric parameters of the watershed have been evaluated. Drainage map of the study area reveals a dendritic drainage pattern with sixth order stream network comprising 492 numbers of streams and confining an area of 129.41 km2. Mean bifurcation ratio (Rb) and stream length ratio (RL) of the watershed evaluated are 3.44 and 0.54 respectively which corroborates the fact that drainage pattern is not influenced by the geological evolutions and disturbances in the recent past. The drainage density of 2.68 kmꞏkm−2 indicates impermeable subsoil material with sparse vegetation and moderate to low relief. Elongation ratio of 0.956 infers the basin to be closer to a circular shape. The geologic stage of development and erosion proneness of the watershed is quantified by hypsometric integral (HI) bearing value as 0.5, indicating the landscape to be uniform and in early mature stage. The study prioritizes eight sub-watersheds as high, medium and low for taking up soil and water conservation activities. Hence, remote sensing applications proved to be highly useful in extracting the precise data for the evaluation and analysis of watershed characteristics.

scholarly journals Morpho-Tectonic Assessment of the Abu-Dabbab Area, Eastern Desert, Egypt: Insights from Remote Sensing and Geospatial Analysis

2021 ◽  
Vol 10 (11) ◽  
pp. 784
Author(s):  
Abdelrahman Khalifa ◽  
Bashar Bashir ◽  
Abdullah Alsalman ◽  
Nazik Öğretmen
Keyword(s):  
Drainage Basin ◽  
Activity Index ◽  
Eastern Desert ◽  
Valley Floor ◽  
Tectonic Activity ◽  
Asymmetry Factor ◽  
Water Drainage ◽  
Stream Length ◽  
Seismic Region ◽  
Hypsometric Integral

The Abu-Dabbab area, located in the central part of the Egyptian Eastern Desert, is an active seismic region where micro-earthquakes (≈ML < 2.0) are recorded regularly. Earthquake epicenters are concentrated along an ENE–WSW trending pattern. In this study, we used morphological indexes, including the valley floor width-to-valley floor height ratio (Vf), mountain front sinuosity (Smf), the asymmetry factor index (Af), the drainage basin shape index (Bs), the stream length–gradient index (SL), hypsometric integral (Hi) water drainage systems, and a digital elevation model analysis, to identify the role of tectonics. These indexes were used to define the relative tectonic activity index (RTAI), which can be utilized to distinguish low (RTAI < 1.26), moderate (RTAI = 1.26–1.73), and high (RTAI > 1.73) tectonic activity signals all over the study area. Firstly, our results indicate low to medium tectonic activity and general anomaly patterns detected along the major tectonic zones of the study area. Secondly, based on most of the low to medium tectonic activity distributed in the study area and the detected anomalies, we discuss two potential drivers of the seismicity in the Abu-Dabbab area, which are fault-controlled and deep-rooted activities.

scholarly journals Using morphometric and geomorphic indices to assess Western São Francisco Craton neotectonic traces

2021 ◽  
Vol 41 ◽  
pp. e184588
Author(s):  
Mário Teixeira Rodrigues Bragança ◽  
Luiz Fernando de Paula Barros ◽  
Déborah de Oliveira
Keyword(s):  
Structural Control ◽  
Tectonic Activity ◽  
Asymmetry Factor ◽  
Southeastern Brazil ◽  
Drainage Network ◽  
Catchment Scale ◽  
Stream Length ◽  
Geomorphic Indices ◽  
Fluvial Morphology ◽  
Hypsometric Integral

Recently, geomorphometric properties of river networks and catchments have been described and applied as an efficient tool in the investigation of the landforms' response to neotectonics. Geometric parameters of the Cotovelo River catchment extracted from an Alos-Palsar digital elevation model were used to compute morphometric and geomorphic indices to investigate whether the bedrock structure and recent active tectonics influence the local drainage network. The Cotovelo catchment is situated in the Middle to Upper Proterozoic western foreland basin of the São Francisco craton, in northwestern Minas Gerais, Southeastern Brazil; it is presumed to be a stable piece of earth’s crust. The automatically generated streams were processed at the sub-catchment scale to calculate the hypsometric integral, relief ratio, stream frequency, and drainage density morphometric indices as well as supported a geomorphic study based on the basin shape, asymmetry factor, valley floor width-to-height ratio, mountain front sinuosity, transverse topographic symmetry factor, and stream-length gradient index. Achieved results revealed recent and low-rate tectonic activity and structural control on the fluvial morphology. Prominent knickpoints, aligned with mapped fault scarps, disclose straight erosive fronts away from stratigraphic borders, indicating these features are unrelated to lithological changes. Despite the catchment location, the area exhibits impressive fluvial anomalies, and dissection occurs preferentially along ancient faults and fractures densely occurring in the rocky strata. Channel parallelism in context of medium to high relief and steep slopes, remarkably structurally drive fluvial dissection, asymmetric and elongated drainage catchments, and aligned landforms suggest neotectonic influence on the drainage network.

scholarly journals Ποσοτική ανάλυση - μορφοτεκτονικοί δείκτες για τις περιοχές των ρηγμάτων Στρατωνίου - Βαρβάρας και Γοματίου - μεγάλης Παναγιάς (Ανατολική Χαλκιδική)

2005 ◽  
Vol 38 ◽  
pp. 14 ◽  
Author(s):  
Α. ΜΙΧΑΗΛΙΔΟΥ ◽  
Α. ΧΑΤΖΗΠΕΤΡΟΣ ◽  
Σ. ΠΑΥΛΙΔΗΣ
Keyword(s):  
Surface Morphology ◽  
Geographical Information Systems ◽  
Drainage Basin ◽  
Active Faults ◽  
3D Models ◽  
Fault Scarp ◽  
Geographical Information ◽  
Stream Length ◽  
Hypsometric Integral ◽  
Mountain Front

The study area is located at the NE part of Chalkidiki peninsula. Geologicaly it belongs at Servomacedonian mass. The faults of Stratoni - Barbara and Gomati- M. Panagia have an important role at the surface morphology of the area. These are typically active faults and they are the most important neotectonic structures at Eastern Chaikidiki. For the study of surface morphology a quantitative morphotectonic analysis has been done with the contribution of Geographical Information Systems GIS. The morphological indicators we have studied are: hypsometric curve and hypsometric integral, drainage basin asymmetry, mountain - front sinuosity, stream length - gradient index, transverse topographic symmetry, radio of valley - floor width to valley height and fault scarp morphology. This morphotectonic analysis has confirmed the field observations. Major role in this research had the use of satellite pictures and 3D models (Digital Elevation Model - D.E.M.).

scholarly journals Μορφοτεκτονική μελέτη της ευρύτερης περιοχής Θεσ/νίκης για τη χαρτογράφηση νεοτεκτονικών ρηγμάτων.

2005 ◽  
Vol 38 ◽  
pp. 30 ◽  
Author(s):  
Α. ΖΕΡΒΟΠΟΥΛΟΥ ◽  
Σ. ΠΑΥΛΙΔΗΣ
Keyword(s):  
Drainage Basin ◽  
Digital Elevation Models ◽  
Active Faults ◽  
Gradient Index ◽  
Stream Length ◽  
Drainage Patterns ◽  
Digital Elevation ◽  
Mountain Front ◽  
Morphotectonic Indices

At this paper studied the neotectonic active faults of the broader area of Thessaloniki with morphotectonic criteria. We have studied three main faults of Anthemounta, Asvestophori and Pylaia - Panorama with the contribution of cartography, digital elevation models, drainage patterns, and the morphotectonic indices like drainage basin asymmetry, mountain front sinuosity, knick points and stream length-gradient index. Those faults show elements of activity.

Building the Professional Services E-Practice

2011 ◽  
pp. 246-260 ◽  
Author(s):  
Dieter Fink
Keyword(s):  
Organizational Development ◽  
World Wide ◽  
Professional Services ◽  
Mature Stage ◽  
The Internet ◽  
Professional Advice ◽  
Services Sector ◽  
Management Consultants ◽  
Virtual Age ◽  
Stage Of Development

Information Technology (IT) has played an important role in the professional services sector for many years. Professional firms such as accountants, lawyers and management consultants have used IT to increase internal efficiencies, and the expertise gained has enabled some of them to offer IT-related professional advice to their clients. Over time, IT has increased in sophistication and we have now entered the Internet or electronic age (e-age) where the letter ‘e’ precedes commerce, business, government, learning and so forth. The emergence of the World Wide Web (Web) on the Internet has created even greater scope for professional firms to manage their internal affairs more efficiently and effectively, and to improve client services. The purpose of this chapter is to provide small professional services practices with an understanding of how to enter the e-age by building an e-practice. It proceeds by mapping the progress that needs to be made in moving from a previous stage of organizational development to one that is suitable for the ‘virtual age.’ In the transition to the mature stage of development, they need to re-engineer their practices to offer online services and to maximize their intellectual capital through technology-enabled knowledge management.

North-South variation in tectonic activity along left-stepping extensional basins revealed by morphometric analysis: Gofa province, southwestern Ethiopia, East Africa

2020 ◽  
Author(s):  
Asfaw Erbello ◽  
Gerold Zeilinger ◽  
Manfred R. Strecker
Keyword(s):  
Strain Localization ◽  
Tectonic Activity ◽  
Southern Ethiopia ◽  
Climatic Data ◽  
Long Term Effects ◽  
Study Region ◽  
The North ◽  
Hypsometric Integral ◽  
Mountain Front ◽  
Channel Steepness

&lt;p&gt;We report on the morphotectonic characteristics in the tectonically active Southern Ethiopia Rift (SER) based on the analysis of high-resolution topographic data (12m TanDemX) and satellite imagery. The study region is a wide zone of distributed extension at the transition from the SER and the Northern Kenyan Rift and reflects the long-term effects of episodic tectonic events in the landscape. &amp;#160;The uplifted footwall margins of the north-south trending and left stepping &amp;#275;n &amp;#275;chelon basins of the SER constitute Pan-African basement rocks in the southern and central part (Chew Bahir, Mali-Dancha and part of Beto) and tectonized Miocene basalts in the north (Sawula). As such this region is an ideal location to record the tectonic characteristics of a major transition zone between two rift systems. Some of the unsolved problems in this area concern the degree of tectonic activity, spatiotemporal variations in the amount of extension, and the nature of kinematic linkage between different faults. To examine these issues, we calculated morphometric indices of river catchments along major fault-bounded blocks as proxies for tectonic activity and combined this information with structural, seismicity, and climatic data.&amp;#160;&lt;br&gt;We determined basin asymmetry, hypsometric integral, mountain-front sinuosity, valley floor to valley-width-height ratio, basin shape, the range of basin form and mean slope; additionally, we calculated knickpoint distributions and channel-steepness index values from 89 sub-basins. Combined, the data suggest a significant north-south variation in extensional processes. For example, in the northern basins knickpoints are generally located in upstream areas near the channel heads. They are rare in the Mali-Dancha basin, whereas in the Chew Bahir basin a distinct distribution along the main channel is recognized from basin head to the mountain front. In the south the knickpoints are closest to the mountain front. This unique spatial arrangement of knickpoints in rivers draining the footwalls of extensional blocks in the north-south transect suggests a gradual, southward-directed shift in extensional deformation and recent tectonic activity. The normalized channel-steepness index value is generally small; however, it also exhibits a significant southward trend with higher values (i.e., tectonic activity). Additionally, the normalized channel steepness indices are higher at orthogonally interacting faults compared to neighbouring areas, suggesting strain localization.&amp;#160;&lt;br&gt;Our new results suggest a northward increase in the geomorphic maturity of the analyzed sub-basins from Chew Bahir (juvenile) to Sawula (mature), which is compatible with a northward decrease in tectonic activity and a dominance of erosional processes. This is consistent with published, northward-decreasing extension rates and the degree of regional seismicity. Furthermore, strain localization at interacting faults suggests kinematic linkage of the left-stepping bounding faults of the sub-basins.&lt;/p&gt;

Effect of Temperature on Initial Feeding in Alevins of Chinook Salmon (Oncorhynchus tshawytscha)

1982 ◽  
Vol 39 (12) ◽  
pp. 1554-1562 ◽  
Author(s):  
T. A. Heming ◽  
J. E. McInerney ◽  
D. F. Alderdice
Keyword(s):  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Food Presentation ◽  
Effect Of Temperature ◽  
Mature Stage ◽  
Growth And Survival ◽  
Fish Size ◽  
Stage Of Development ◽  
Active Feeding ◽  
Feeding Zone

Growth and survival of chinook salmon (Oncorhynchus tshawytscha) during the transition to active feeding were examined in relation to the timing of initial food presentation at 6, 8, 10, and 12 °C. The transition to active feeding in these salmon involved a period of "precocious feeding" during which ingestion of food had no effect on fish size, growth rate, or survival. Initial utilization of food for growth and survival did not coincide with any specific stage of development, but rather it occurred earlier and at a less mature stage of development at higher temperatures. Delays in initial food presentation beyond this point reduced fish size and survival. Temperature and the timing of initial food presentation interacted to create a zone of optimum feeding. Biomass production was maximized when alevins began to feed within this zone, independent of the precise time of initial food presentation or temperature. This optimum feeding zone existed at temperatures below 12 °C, between 905 thermal units (tu) postfertilization and a point (F, tu) which varied with temperature (T, °C) as F = 1201.1 − 20.3 T.Key words: temperature, initial feeding, Oncorhynchus tshawytscha, fish culture

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