Appraisal of active tectonics in Hindu Kush: Insights from DEM derived geomorphic indices and drainage analysis
Landscapes in tectonically active Hindu Kush (NW Pakistan and NE Afghanistan) result from a complex integration of the effects of vertical and horizontal crustal block motions as well as erosion and deposition processes. Active tectonics in this region have greatly influenced the drainage system and...
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Elsevier
2012-07-01
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| Series: | Geoscience Frontiers |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S1674987111001265 |
| _version_ | 1797709276265840640 |
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| author | Syed Amer Mahmood Richard Gloaguen |
| author_facet | Syed Amer Mahmood Richard Gloaguen |
| author_sort | Syed Amer Mahmood |
| collection | DOAJ |
| description | Landscapes in tectonically active Hindu Kush (NW Pakistan and NE Afghanistan) result from a complex integration of the effects of vertical and horizontal crustal block motions as well as erosion and deposition processes. Active tectonics in this region have greatly influenced the drainage system and geomorphic expressions. The study area is a junction of three important mountain ranges (Hindu Kush-Karakorum-Himalayas) and is thus an ideal natural laboratory to investigate the relative tectonic activity resulting from the India-Eurasia collision. We evaluate active tectonics using DEM derived drainage network and geomorphic indices hypsometric integral (HI), stream-length gradient (SL), fractal dimension (FD), basin asymmetry factor (AF), basin shape index (Bs), valley floor width to valley height ratio (Vf) and mountain front sinuosity (Smf).
The results obtained from these indices were combined to yield an index of relative active tectonics (IRAT) using GIS. The average of the seven measured geomorphic indices was used to evaluate the distribution of relative tectonic activity in the study area. We defined four classes to define the degree of relative tectonic activity: class 1__very high (1.0 ≤ IRAT < 1.3); class 2__high (1.3 ≥ IRAT < 1.5); class 3—moderate (1.5 ≥ IRAT < 1.8); and class 4—low (1.8 ≥ IRAT). In view of the results, we conclude that this combined approach allows the identification of the highly deformed areas related to active tectonics. Landsat imagery and field observations also evidence the presence of active tectonics based on the deflected streams, deformed landforms, active mountain fronts and triangular facets. The indicative values of IRAT are consistent with the areas of known relative uplift rates, landforms and geology. |
| first_indexed | 2024-03-12T06:35:07Z |
| format | Article |
| id | doaj.art-733e9b1f84434354b417d02add9f64e4 |
| institution | Directory Open Access Journal |
| issn | 1674-9871 |
| language | English |
| last_indexed | 2024-03-12T06:35:07Z |
| publishDate | 2012-07-01 |
| publisher | Elsevier |
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| series | Geoscience Frontiers |
| spelling | doaj.art-733e9b1f84434354b417d02add9f64e42023-09-03T01:24:20ZengElsevierGeoscience Frontiers1674-98712012-07-013440742810.1016/j.gsf.2011.12.002Appraisal of active tectonics in Hindu Kush: Insights from DEM derived geomorphic indices and drainage analysisSyed Amer Mahmood0Richard Gloaguen1Remote Sensing Group, Institute of Geology, Freiberg University of Mining and Technology, Bernhard V. Cotta Str. 2, 09599 Freiberg (Saxony), GermanyRemote Sensing Group, Institute of Geology, Freiberg University of Mining and Technology, Bernhard V. Cotta Str. 2, 09599 Freiberg (Saxony), GermanyLandscapes in tectonically active Hindu Kush (NW Pakistan and NE Afghanistan) result from a complex integration of the effects of vertical and horizontal crustal block motions as well as erosion and deposition processes. Active tectonics in this region have greatly influenced the drainage system and geomorphic expressions. The study area is a junction of three important mountain ranges (Hindu Kush-Karakorum-Himalayas) and is thus an ideal natural laboratory to investigate the relative tectonic activity resulting from the India-Eurasia collision. We evaluate active tectonics using DEM derived drainage network and geomorphic indices hypsometric integral (HI), stream-length gradient (SL), fractal dimension (FD), basin asymmetry factor (AF), basin shape index (Bs), valley floor width to valley height ratio (Vf) and mountain front sinuosity (Smf). The results obtained from these indices were combined to yield an index of relative active tectonics (IRAT) using GIS. The average of the seven measured geomorphic indices was used to evaluate the distribution of relative tectonic activity in the study area. We defined four classes to define the degree of relative tectonic activity: class 1__very high (1.0 ≤ IRAT < 1.3); class 2__high (1.3 ≥ IRAT < 1.5); class 3—moderate (1.5 ≥ IRAT < 1.8); and class 4—low (1.8 ≥ IRAT). In view of the results, we conclude that this combined approach allows the identification of the highly deformed areas related to active tectonics. Landsat imagery and field observations also evidence the presence of active tectonics based on the deflected streams, deformed landforms, active mountain fronts and triangular facets. The indicative values of IRAT are consistent with the areas of known relative uplift rates, landforms and geology.http://www.sciencedirect.com/science/article/pii/S1674987111001265Active tectonicsGeomorphic indicesIRAT (index of relative active tectonics)Hindu KushPakistan–Afghanistan |
| spellingShingle | Syed Amer Mahmood Richard Gloaguen Appraisal of active tectonics in Hindu Kush: Insights from DEM derived geomorphic indices and drainage analysis Geoscience Frontiers Active tectonics Geomorphic indices IRAT (index of relative active tectonics) Hindu Kush Pakistan–Afghanistan |
| title | Appraisal of active tectonics in Hindu Kush: Insights from DEM derived geomorphic indices and drainage analysis |
| title_full | Appraisal of active tectonics in Hindu Kush: Insights from DEM derived geomorphic indices and drainage analysis |
| title_fullStr | Appraisal of active tectonics in Hindu Kush: Insights from DEM derived geomorphic indices and drainage analysis |
| title_full_unstemmed | Appraisal of active tectonics in Hindu Kush: Insights from DEM derived geomorphic indices and drainage analysis |
| title_short | Appraisal of active tectonics in Hindu Kush: Insights from DEM derived geomorphic indices and drainage analysis |
| title_sort | appraisal of active tectonics in hindu kush insights from dem derived geomorphic indices and drainage analysis |
| topic | Active tectonics Geomorphic indices IRAT (index of relative active tectonics) Hindu Kush Pakistan–Afghanistan |
| url | http://www.sciencedirect.com/science/article/pii/S1674987111001265 |
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