INTRODUCTION: As we know, geomorphology is one of the important branches of physical geography that seeks to describe, explain, and interpret the roughness and ruggedness of the earth crust and their development and evolution from a systematic attitude. It should be noted that geologists often focus on the age and formations of such roughness whereas geomorphologists mainly analyze formations and rugged topography and their developments. Since the landforms and ruggedness are developed as a result of various endogenous and exogenous factors, other branches of earth sciences, particularly geology and climatology provide the basic data for the analysis of rugged systems utilized by geomorphologists. In this regard, it should be said that cuestas are the expression of extensive outcrops of gently dipping strata, typically sedimentary strata, that consist of alternating beds of weak or loosely cemented strata.As such, in most parts of the planet, especially in the arid and desert land, cuestas can be found. Nonetheless, there are many controversies about the existence of cuesta in Iran, as some believe that there are no instances of cuesta in Iran whereas others, including the author, can offer hard evidences that prove the existence of cuesta in Iran. This article is an attempt to support this claim.

There are several interrelated problems in landscape developments in unstable SLOPES. These should be classified according to severity and considered before any construction. It is also necessary to monitor and control some stability problems after the construction. Evidently landscape developments, in turn, affect the stability of SLOPES. Unstable SLOPES are basically those SLOPES where distinguishable signs of structural movement can be seen either on the surface area or in the subterranean part. Doubtlessly, it is practically impossible to distinguish between various movements in unstable SLOPES as all of these movements occur simultaneously or with little precedence in the same slope. There are a number of direct or indirect symptoms which are generally observed during the construction or use of landscape developments, namely: cracking, creeping, shrinking, bulging, and tilting of retaining walls as well as appearance of buried elements such as water pipes and roots.

In this paper, stability of SLOPES with a shallow foundation located on top including the shape of the failure mechanism is investigated in static and seismic states. This is a three dimensional problem which is analyzed two dimensionally because 3D analyses are complex and appropriate softwares are not available. The conventional method of bearing capacity evaluation of foundations on top of SLOPES is reviewed and results are compared with those obtained from using a specific three dimensional slope stability algorithm based on upper bound limit analysis theorem. It is concluded that increasing the foundation load to a threshold level, the effect of the load on the stability of the SLOPES is negligible, a phenomenon which can not be observed in two dimensional analyses. Determination of this threshold by 3D analyses is a useful criterion for selection of the adequate safety factor in static and seismic slope stability analyses.

Sloping ground near the footings have an adverse effect on their performance. Slope increases the settlements of the footings and while it reduces their bearing capacity. In the present paper, a footing with rough base has been considered for the analysis. The bearing capacity factors have been determined with the consideration of resistance of soil above the foundation level. A simple limit equilibrium method has been used to evaluate bearing capacity. The parameters considered for the analysis include the distance between edge of slope and center of footing, slope angle and foundation depth. It is observed from the analysis that bearing capacity reduces as distance between footing and the edge of the slope decreases. Increase in slope angle cause the reduction in the bearing capacity.

Upper bound limit analysis method is applied to determine the required reinforcement for three-dimensional stability of the SLOPES under seismic conditions. Horizontal blocks are used for determining the internal stability in three dimensional conditions. Seismic stability is studied by adopting a pseudo-static approach, considering only the horizontal acceleration. Reinforced soil has been considered to be a cohesionless material in the analysis. The failure mechanism is considered to be transitional and consists of several horizontal hexagonal blocks and a pentagonal one at the base. Velocity discontinuities between blocks are considered to be horizontal and each block consists of one reinforcement layer. Results are presented in graphical and tabular form to illustrate the effects of variation of different parameters such as seismic acceleration, three-dimensional geometry of the slope and soil friction angle on required reinforcement length and strength. By increasing of seismic acceleration, the stability of the reinforced soil slope decreases significantly, and thus greater strength and length of the reinforcement are required to maintain stability of the slope. On the other hand, three-dimensional modeling of reinforced slope results lower values of the required reinforcement. Comparisons of the present results with available pseudo-static results are shown, and discussed.

Debris flow is one of the most slope processes and material movement caues morphogens and increasing sediment load in rivers. This study aims debris flow in Northern Alvand SLOPES located in 15 Km distance far from Hamedan city by using aerial photograph and topography maps with 1:50000 and 1:25000 scales and ArcGis9 software. Total 44 samples from sample from debris flows are randomly selected for morphometry parameters such as liner section flow, deeps section, core width, slope and height using observation and measurement statistical real analysis regretion employing SPSS and Microsoft Excel software's. The deep section and slope volume debrises are modeled by deep erosion and weathering slope material measurement tool. Results showed that height and slope are most important parameters in the effects parameters in caues debris flow in studied region. On the other hand, debris flow concen tration are spread in 2700-3000 m altitude shows lithology tectonic and nivation with perglaciear erosion system effects in formation and development of debris flow. In addition, the results if this study based on the Cain and Biljinberg formula reveled that occurring precipitation in 15 to 105 minute ranges in some year's caues debris flow motion in the SLOPES and subsequently inside the rivers, resulting in increasing sediment load in rivers and denudation SLOPES in studied region.

The present paper reveals the results of an analytical method to calculate the bearing capacity of a footing supported on one or two rows of piles stabilizing slope. The varied parameters here include pile diameter, pile length, location of pile rows, location of footing relative to the slope crest, foundation width, center to center spacing of piles in a row, and fixity of the pile head. Passive pile resistance is determined based on normal and shear resistance of the soil surrounding the pile considering plastic deformation of soil between piles. The Pile resistance obtained through the present method is compared with other analytical as well as 3D numerical ones. The results indicate acceptable agreement. The footing bearing capacity is calculated according to both the limit equilibrium slope stability analysis and soil stability beneath the footing. The predicted results were compared with those reported from other experiments and indicated an acceptable agreement with increasing pile spacing. The results indicate that stabilizing the earth slope with rows of piles has a significant effect on the footing of bearing capacity improvement.