International Research Journal of Applied and Basic Sciences. Vol., 3 (2), 224-233, 2012 Available online at http://www.irjabs.com ISSN 2251-838X Geomorphologic Evidences of the Influence of Glacier Sediments in Lake Formation Case Study: the Formation of Gahar Lake, in Iran Ali mohamad Yarahmadi 1* , Ebrahim Moghimi 2 , Mohamad Reza Servati 3 , Parviz Kardavani 4 1. Department of Geography, Science and Research Branch, Islamic Azad University, Tehran, Iran. 2. Professor of Physical Geography Geography College, University of Tehran, Tehran, Iran. 3. Professor of Geography Geography College, University of Shahid Beheshti, Tehran, Iran. 4. Professor of Geography Department of Geography, Science and Research Branch, Islamic Azad University , Tehran, Iran. * Corresponding author: Ali mohamad Yarahmadi ! ""1885666. Phon #$%#& 06654242580 ABSTRACT: The existence of the glacier forms represents the function of the glaciers in development and evolution of the earth surface. Gahar Lake in Iran is one part of the old and cold climate heritage still existing in today warm and half-dry climate of Iran. This lake is located in the southern slope of Oshtorankuh in a fault valley having the area of about 88 ’%% ( ) ’" * %’% Previous researches claim that the formation of this lake was due to the landslide. This is the question of this research; what is the effect of the process of glacier sediments in formation of this lake? This research has been done by using field study, the study of mass deformation of shapes, and by using ETM sensor images, aerial photos, topography and geological maps. The results show that moraines Sholila and Ghiff Glacier valleys have caused the formation of the Gahar Lake. They have done this by moving and locating against the flowing of the Gahar River. The spectral reflection of the blocking sediments of the lake corresponds to the sample sediments of moraine present in the center of Sholila and Ghif circuses. Therefore, the lake has been formed due to the movement and situating of the glacier sediments. So it is considered as the heritage of cold climate of Iran, and tectonic and sliding origin of its formation proves invalid. Keywords: Gahar; Glacier sediments; Geomorphology; Lake; Oshtorankuh; Zagros. INTRODUCTION Knowing the forms resulted from the effect of climate and their deformation as well as any activity deforming the shape of the earth and causing the displacement of materials and changing the quality and quantity of their kinetic energy are considered by geomorphologists (Moghimi, 2008). Landforms can be guidance in relation to recognition of their own producing factors. Of course, when the producing factors are numerous and they have combined function or they don't have a desired chronological order, the task will not be easy (Moghimi and mahmoodi, 2004). Glaciers and their sediments influence on the different aspects of human life and the environment. So, their study is critical for understanding and forecasting global environmental change (Knight 2006; Hastenrath 2008). On the other hand, the studying of landforms of the ice age provides the valuable information about paleoclimate conditions (Loso et al., $$"+ ,$""+ ! * ) ! one of the most significant heritages of climate evolutions of the quaternary period in Iran. Paying attention to deformation of the forms in the case of their mass and the spectral reflection of the sediments is among the methods that can be used to understand the changes and displacement of quaternary sediments. The study of glacier areas and registering and providing the map of these areas are some of the most important applications of this technology. Among scientists who use this technology we can refer to Kulkarni (1991, 1994), and Kulkarni and Buch (1993) who mapped the Himalayan glaciers on 1:250.000 scale by using Landsat data. Philip and Ravindran (1998) have also mapped glacier landforms of Gangotri