The new plate tectonics theory acquired a position in sea floor geomorphology as .applied to interpretation of mountain topography within continent-ocean sutural zones. The question of the day is the theory application to mountain relief analysis within intracontinental sutural zones. The problem both of interest and importance is elaboration of consistent hypothesis of orogenesis on the basis of geosynclinal theory and plate tectonics taking into consideration recent progress in the Earth sciences. The first step should be development of an up-to-date typology of mountains summing up results of regional studies.

On the average the mechanic erosion values at Subarctic and temperate zone mountains exceed those of plains (under the same landscape conditions) by factor 2,5 to 3. The erosion rate increases eastward due to increase of the climatic continentality. Within mountain regions the mechanical erosion intensity is controlled by a series of factors, the most important being land-scape-climatic conditions and rocks' composition. The human economy impact is of much importance in regions of high economic development. In the forest zone the mechanical erosion is less than the chemical one, and in the mountain tundra it exceeds the chemical erosion considerably.

Morphology of the three main depressions of the Philippine Sea floor is discussed. Special attention is paid to comparative characteristic of fault zones which most specialists believe to be of spreading type. Structural prolongation of the Jap trough northward is proved to be the fault Jap and submarine mountain chain Kienan. In the 17th voyage of the «Dmitry Mendeleev» vessel a survey of the southern part of the fault zone was carried on, the maximum depth measured being 6900 m. The central fault of the Philippine basin is proved not to exceed the bounds of the depression and not, to reach the Taiwan Island as it was thought before. The sea floor topography near the junction of the Jap and Mariana troughs represent a system of fan-like depressions and ridges, the maximum depth being 8000 m. Bathymetric map of the sea was verified and a geomorphological map has been compiled.

The author puts emphazis on an importance of geological structures for the existing Alpine relief understanding. The relief of the North-West (French) Alpes is controlled by tectonics and lithology in its broad outlines. At the same time the erosion intensity is so great in the Alpes that geomorphological description requires thorough analysis of morphosculpture.

A scheme of the Pleistocene accumulation plains of the North Yakutia is stated. Three sedimentation areas are distinguished along the main rivers: intermountain and foothills, intracontinental plains, coastal plains. In the cross-section of the valleys the authors distinguish an axial and two marginal zones. The axial zone is characterized with mostly channel and delta sediments, the marginal zones-with so-called «yedoma» series, presented by silt with high ice content; the silts belong to various faces of alluvial, proluvial and slope deposits. The original yedoma appearance is best conserved in the intermountain and foothill areas, where terrasouvals exist. Within intra continental and coastal plains the primary relief has been changed into alas and alas-valley topography.

The mountain belt of the Andes was subdivided (using formalized attributes) into mountain countries, megablocks and blocks which are divided with lineaments of 1st, 2nd and 3rd rank and main shift zones. The established transversal lineaments are manifested in relief by system of linear depressions (including linear reaches of valleys), steps and scarps. The lineaments divide regions differing in the relief's appearance (altitudes and direction of topographic elements as well as their combinations), in rocks age and thickness, in volcanism type. In general the large subdivisions (mountain countries) coincide with regions distinguished by other research workers. Many of transversal lineaments (mostly those of. the 3rd rank) are first established by the author. Epicenters of strong crustal earthquakes are situated at lineaments junctions. The earthquakes of that type are not known in volcanic mountain countries.

The climate is considered to be a main factor controlling type of morphogenesis, the latter being characterized by a certain «spectrum» of exogenous processes and resulted landforms. «Stepped» structure of the structural plains was formed during the Quaternary under condition of cyclic changes of climate which resulted in repeated changes of climatic-landscape zones and morphogenesis' types. Stepped structure is associated (in time and space) with semiarid morphogenesis, the main manifestation of the latter being an active planation process of the pediplanation type.

Studies of zones of erosion, transport and aggradation in slope rills (micro-channels) and field experiments confirmed the possibility of deluvial slope apron formation at most part of slope under conditions of constant slope angle but decrease in water discharge downslope. Most important feature of the channel erosion on slopes (no matter what are the channel's parameters) is formation and movement of vertical scarps at the floor. The phenomenon should be taken into consideration when methods of slope wash estimation are worked out.

A new chronological classification is introduced for fluvial terraces of the Kuma and Podkumok rivers based on the terraces' mapping, on their correlation with transgressive levels of fluvio-marine plains of the Caspian region and dated planation surfaces within the mountain area, and on the analysis of geomorphic position of fossil mammals in the Mashuk's travertines. The author distinguishes the Holocene low and high floodplain levels, 4 terraces of Late Pleistocene age, 2 terraces of Middle Pleistocene age and 2 of Early Pleistocene age as well as Apsheronian and Akchagylian topographic levels.

Subaqueous topography of the Baikal depression presents typical features of intercontinental rift structure. The conditions of the Baikalian rift formation are reflected in differences in structure, width and angle of the rift's opposite slopes, in faults traces at the rift depression floor, in linear troughs along the western footslope and other features of morphology.

A regional geomorphic level has been studied in the Muya Depressions system (Centra] Stanovoye Upland), the former being restricted to 800-900 meters a. s. l. Its origin is due to a Middle Pleistocene large water basin which spread far southwards into the Transbaikalian region along the Vitim drainage basin.

The highest level of the basin was simultaneous to the maximum (Samarovo) stage of the Stanovoye Upland glaciation and resulted from the Vitim River damming by glaciers descending from the North Muya, Delyun-Uran and Kodar Ridges. The regional geomorphic level is a unique reference level for measurement of Middle and Late Pleistocene tectonics, the level's distortion due to Late Pleistocene movements being up to 50 meters.

The marginal glacial zones are established to be more widespread in the region than they were thought before. Local moraines are proved to exist almost all over the southern part of the region. The data allow changing the boundary of the Dnieper glaciation.

Climatic rythms manifested in terrace series (answer to critical review by O. K. Leontyev and S. V. Lutsau)

Sea coasts erosion

Problems of structural geomorphology, neotectonics and geodynamics of the Caucasus

Problems of geomorphology at the XXIV International Geographical Congress