Mohammad Mahdi Hoseinzadeh; Saeed Rahimi Harabadi
Volume 22, Issue 87 , November 2013, , Pages 77-80
Abstract
Exploring the changing processes of land forms is considered to be one of the key topics in geomorphological studies. Nowadays, geomorphological studies analyzes and clarifies geomorphic forms and processes at ground level. This shows the dominance of a systematic view in this field. In systematic view, ...
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Exploring the changing processes of land forms is considered to be one of the key topics in geomorphological studies. Nowadays, geomorphological studies analyzes and clarifies geomorphic forms and processes at ground level. This shows the dominance of a systematic view in this field. In systematic view, geomorphic analyses are performed based on the relation between land form and process. Geomorphologic threshold is one of the key concepts in systematic theory and thus is of significant importance in geomorphology. It indicates borderline situations during the occurrence of changes and shows temporal changes. The present article is based on secondary research and exploits theoretical and applied concepts related to thresholds, seeking to reach a balanced systematic analysis. It tries to study geomorphologic thresholds and classifications using different Persian and English resources. Moreover, we propose a short overview of some geomorphological issues, such as gully erosion, alluvial fan and river systems. Results indicate that geomorphic thresholds separates different situations of a system and are thus distinguishable. In fact, occurrence of a threshold changes the dominant processes in a geomorphologic system. This concept shows the situation in which a process operates to establish a new balance in the system. Siyum classifies geomorphic thresholds into two categories: 1) Internal which is related to the inside of a geomorphic system and 2)external which is under the influence of external variables such as climatic and tectonic changes.
Reza Esma'ili; Mohammad Mahdi Hosseinzadeh
Volume 18, Issue 71 , November 2009, , Pages 77-80
Abstract
The application of geological data in view of the recent advances in Paleoflood hydrology is essential as a complement to conventional hydrological approaches. The utilization of geological data such as sedimentology, stratigraphy and their combination with other sciences, such as geomorphology and hydrology, ...
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The application of geological data in view of the recent advances in Paleoflood hydrology is essential as a complement to conventional hydrological approaches. The utilization of geological data such as sedimentology, stratigraphy and their combination with other sciences, such as geomorphology and hydrology, have been particularly considered due to the existence of ambiguities in the mere use of applied statistics in flood studies. These data provide information from rivers without a hydrometric station. It is also possible to obtain longer information from hydrometric stations by using these data. The most important methods that are considered in this approach are: river flow regime method, Paleolithic Standard Indexes, river flow potentiality method, and botanical methods.
