A study of knickpoint surveys and their likely association with landslides along the Hunza River longitudinal profile
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Mass wasting and tectonic uplift are the major factors, responsible for reshaping the northern Pakistan that contains the world’s most steeply inclined mountainous regions including: Karakoram, Himalayas, and Hindukush Ranges. The role of GIS and remote sensing is inevitable to study the river geomorphology for the identification and evaluation of different mass wasting processes. digital elevation models (DEMs) are frequently used to extract the longitudinal profile of the rivers to identify the knickpoints and their related geomorphic attributes. For this study, ASTER DEM of 30 m spatial resolution satellite data was utilized to perform the geomorphological analysis of the longitudinal profile of the Hunza River in ArcGIS and Matlab environment. The Hunza River channel with having the watershed area of 13571 km2, has witnessed a number of historic landslide dams (i.e. Attabad, Ganesh and Boultar glacier, etc.) that blocked the main river channel at multiple sections in different episodes of time. These past landslides presumably preserved in the river channel as knickpoints at their respective locations. In this study, a total of 77 knickpoints were identified along the main stem of the river channel. The spatial locations of the extracted knickpoints and their normalized steepness index (ks) values were compared with the Hunza River landslide inventory map, lithologic contact, tectonic faults and historic landslides data. Furthermore, the likely role of these geomorphic factors was evaluated to ascertain their association with knickpoints formation. The results of this GIS-based geomorphic analysis of the river profile and subsequent field visit of the area revealed that the formation of landslide dams and their subsequent breaching is one of the major trigger factor of knickpoints along the channel. Such studies highlight the benefits of inexpensive remote sensing data and GIS tools to assess the likely role of various geomorphic features in the formation of significant knickpoints along the river profiles on a regional scale.
KeywordsKnickpoint Longitudinal profile Hunza River Landslide Dam Karakoram Range
The authors wish to thank the University of Engineering and Technology, Lahore Pakistan, for their financial support to conduct this study and the anonymous reviewers for their valued comments on the original manuscript to make it refined for the eventual publication.
- Ahmed MF, Rogers JD (2013) Thalweg profiles and knickpoints as useful discriminators of prehistoric landslide dams in Northern Pakistan: In: 125th annual meeting Geological Society of America, Denver, Colorado 45:7Google Scholar
- Angillieri MYE, Perucca L, Vargas N (2017) Catastrophic flash flood triggered by an extreme rainfall event in El Rodeo village, January 2014. Northwestern Pampean Ranges of Argentina, Geografiska Annaler: Series A. Phys Geogr 99(1):72–84. https://doi.org/10.1080/04353676.2016.1263022 CrossRefGoogle Scholar
- Frankel KL, Dolan JF, Finkel RC, Owen LA, Hoeft JS (2007) Spatial variations in slip rate along the Death Valley-Fish Lake Valley fault system determined from LiDAR topographic data and cosmogenic 10Be geochronology. Geophys Res Lett 34(18):L18303. https://doi.org/10.1029/2007GL030549 CrossRefGoogle Scholar
- Hack JT (1973) Stream-profile analysis and stream-gradient index. J Res US Geol Surv 1:421–429Google Scholar
- Hewitt K (1982) Natural dams and outburst floods of the Karakoram Himalaya. IAHS 138:259–269Google Scholar
- Kazmi AH, Jan MQ (1997) Geology and tectonics of Pakistan. Graphic Publishers, Karachi, p 554 (9698375007)Google Scholar
- Owen L (1991) Mass movement deposits in the Karakoram Mountains: their sedimentary characteristics, recognition and role in Karakoram landform evolution. Zeitschrift fur Geomorphologie NF 35:401–424Google Scholar
- Shahzad F, Mahmood SA, Gloaguen R (2007) Stream Profile and Neotectonic Analysis in Hazara Kashmir Syntaxis using Shuttle Radar Digital Elevation Data. 10.1109/ICET.2007.4516321Google Scholar
- Walsh LS, Martin AJ, Ojha TP, Fedenczuk T (2012) Correlations of fluvial knickzones with landslide dams, lithologic contacts, and faults in the southwestern Annapurna Range, central Nepalese Himalaya. J Geophys Res 117:1–24Google Scholar
- Wobus C, Whipple KX, Kirby E, Snyder N, Johnson J, Spyropolou K, Sheehan D (2006) Tectonics from topography: procedures, promise, and pitfalls. Geol Soc Am Spec Papers 398:55–74Google Scholar