Geographical studies and environment protection research
Volume X | Issue 1
Glacial and Periglacial Relief in the Făgăraş Mountain, with Special Focus on the Vâlsan River Basin
Abstract: The glacial modeling has created two well individualized geomorphologic landscapes in the Transylvanian Alpes: Borăscu, characterized by the large extension of the platform and high peaks, and Făgăraş, where cirques were multiplied and have developed until they reduced the platform to a very sharp ridge (gipfelflur). The layout of the main ridge on the West-East direction and the overall morphography of the two slopes, the northern one short and steep and the southern long, with gentle slopes, were also reflected in the way of development of glaciers in the Quaternary. In the Vâlsan basin there are distinguished some particularities of the glacial landform. Thus, the glacial landform of this sector of the Făgăraş Mountains is characterized by a small steep (200-300 m) which favored the development of a long glacial valley with gentle slopes and led to the forming of the moraines at the glacial valley floor. The Vâlsan glacial cirque is at 2300 m altitude, is small and has small lakes. The bottom of the cirque is flat and is predominantly grafted on mica-schist and gneisses. The Vâlsan glacial valley is North-South oriented and has several glacial thresholds. The slopes surrounding the Vâslan valley are symmetrical, being affected by torrents and avalanches. Other characteristic landforms are: narrow glacial crests, glacial replats ridges, nunataks and moraines. The frost wedging caused the residual relief represented by sharp ridges, peaks, landforms of accumulation, debris cones, glacis, stone arches, protalus ramparts. Overall, the Vâlsan glacial valley is a typical valley where the intensive post-glacial processes have hidden most of the features resulting from the glaciers action, which kept the characteristic „U” shape and the glacial replats appear from place to place under glacises and rock debris.
Volume X | Issue 1
Typological and Morphometric Characteristics of the Glacial Cirques in Doamnei River Basin (Făgăraş Massif)
Abstract: The Doamnei River basin, situated on the southern slope of the Făgăraş Massif, is a proper field to study the glacial landforms, because it preserves the two types of glacial landscape identified by Emm. De Martonne even since 1907 for the Meridional Carpathians: the Făgăraş glacial landscape (typical alpine landscape) and the Borăscu glacial landscape. This paper intends to explain some theoretical and practical aspects regarding the correct definition and identification of glacial cirques, and to provide a glacial typology that includes morphological, genetic and topographic criteria. The paper also contains a geomorphologic map (the result of a more extensive analysis) of the glacial landforms in the Doamnei River basin (with 7 glacial complexes, isolated glacial cirques, glacio-nival cirques), the periglacial landforms and the Borăscu erosion surface.
Volume X | Issue 1
The Landforms of the Făgărăș Mountains (The Argeș Mountain Catchment): Analysis of the Related Dynamic Processes
Abstract: The present configuration of the Făgăraş Mountains is a snapshot of the long-term evolution that brought about significant alterations of the landscape, and especially of the relief, which has acquired different features depending on the intensity of the relationship between the exogenous and endogenous agents. Relief shaping in the study area is controlled by the orographic and climatic features. However, the climate of the high and middle-height mountains is the main cause that determines the mechanism, the intensity and the spatial distribution of the shaping processes. The massiveness and the considerable height of the Făgăraş Mountains, which exceed 2500 m altitude (Moldoveanu peak 2544 m, Negoiu peak 2535 m, Lespezi peak 2522 m, Vanatoarea lui Buteanu peak 2507 m, etc.), are responsible for the vertical zonation of climate and vegetation. The study area lies in the middle of the Southern Carpathians range, on the southern slope of the Făgăraş Mountains (the Arges mountain catchment). The scale of investigated phenomena and the frequency of their occurrence allow us to distinguish two types of different phenomena on the basis of their geological or geomorphological origin. Each slope section was analyzed by using a series of parameters considered as being stable from the morphodynamic point of view.
Volume X | Issue 1
Types of Riverbed along the Lower Course of the Buzău River
Abstract: In the present study there were analyzed two sectors of river bed, located along the lower course of the Buzau River: Vadu Paşii – Săgeata (sector of braided channel) and Ibrianu – Custura. Through the calculation of some indices (the braiding index, the sinuosity index), the performance of correlations between elements established through measurements (length and amplitude of the meanders, the width of the river bed) could be differentiated the types of river beds. By analyzing the Austrian maps in 1910, of the topographic maps, orthophotoplans and Landsat images from 1987, 2000, 2006 and 2007 it could be observed the spatial dynamics of the specific element of each type of river bed. For the Vadu Paşii – Săgeata sector the braiding index reduced from 3.4 in 1981 to 2.32 in 2005. In the Ibrianu –Custura sector, there took place many underpinnings at the level of the complex meanders, and the length of the river reduced from 36.4 km to 24.5 km.