Preview

Геоморфология

Расширенный поиск
№ 1 (2003)

Общетеоретические статьи

3-8 201
Аннотация
An analysis of factual data on volcanic eruptions (during the period of 1900 to 1977) has revealed a pattern in eruptions distribution over latitudinal zones of the Earth and elucidated special features of the distribution related to the Earth's rotation and precession of its axis. The general rotation-dependent regularity consists in total number of eruptions decreasing from; it is complicated by regular alternation of zones of active volcanism and relatively quiet zones. The distribution of eruptions resembles a standing wave with vibration amplitude damping out towards from equator toward poles; it reflects wave character of processes of crustal deformation of the Earth ellipsoid. The wave length is ~20° of latitude in the Northern Hemisphere and ~15° in the Southern Hemisphere. Maximums are at 15-20°, 35—40°, 55-60° in the Northern Hemisphere, and at 0-10°, 20-25°, 35—40° and 50-55° in the Southern one. The rate of eruptions decrease with latitude amounts to about 3 eruptions per 1° in the Northern Hemisphere and about 5 in the Southern. Distribution of seismic events over latitude was analyzed using USGS/NEIC Significant Worldwide Earthquakes database. Some regularities in earthquakes number changes with latitude have been established for both hemispheres.
9-14 214
Аннотация
During the Meso-Cenozoic time, changes of climate resulted more than once in that exogenic morphogenesis types replaced one another and relief underwent restructuring. It should be noticed, however, that though new land-forms evolved in the process, some of older once persisted as relicts from former climates. There is a distinct zonality in distribution of relict landforms over plains of Europe.
15-24 213
Аннотация
Evolution of thermal abrasion coast is simulated by analogy with sedimentary coast erosion, but taking into account additional losses of material due to thermodynamic phenomena. The net contribution from the latter to the sediment budget is presented as excess sediment input from the coastal zone (qT). With such an approach, the problem amounts to determination of storm-induced changes in coast profile and quantitative estimate of q T. The first task is solved using the author's model of sedimentary coast evolution. The thermodynamic constituent q T is estimated from empirical data on thermal erosion of the East Siberian Sea coasts. The q T value is supposed to be bounded by saturation limit controlled by both local climatic parameters and the cliff height. The model seems to be in good agreement with available data. It has been also used to predict thermal-abrasion cliffs evolution in the Laptev and East Siberian seas for the next 100 years with regard for global warming. The results suggest the rate of cliff recession to increase by 40-50% in the second half of the century as compared to the present-day.
25-36 197
Аннотация
An analysis of landforms shown in paintings of different peoples revealed a certain similarity between evolution of art in Europe and development of modern science. Both the science based on culture of the European mega-ethnos and the painting of European artists show similar succession of stages since Early Renaissance. The modern science and landscape painting were fully formed in 16 thcentury and develop in amazing agreement since then.

Дискуссии

37-39 207
Аннотация
The author disagrees with N.I. Nikolaev's opinion on the identity of neotectonic and geomorphologic stages in the Earth's evolution. The notion on the geomorphologic stage of evolution has not lost its significance, on the contrary, it has acquired more solid theoretical base.
40-48 200
Аннотация
The paper presents regional classification of morphogenetic type consisting of three taxonomic categories. Taxa of every level are typological units with corresponding archetypes. The lowest category is geomorphic facies defined by predetermined assortment of macro- and micromorphological characteristics including steepness (inclination) of elementary surfaces and properties of loose deposits. Probabilistic distribution of slope facies steepness shows pronounced polymodality. Taxa of second and third rank are typified using generalized characteristics.

Научные сообщения

49-55 186
Аннотация
Of the main ways of gold placers exploitation, the most devastating for environments is dredging. The paper considers environmental consequences of dredge usage for placer mining in mountain rivers of medium order. The intensity of impact on channel system depends on the work duration and area, as well as on characteristics of regional environments. Capability of river to restore the channel characteristics after placer has been abandoned is found as relationship of sum of the river discharge and gradient to degree of disturbance.
56-64 183
Аннотация
Progressive changes in erosion processes in South America and Australia during the second half of 20 th century are established on the basis of direct (suspended load dynamics) and indirect (rainfall dynamics and human activities) evidences.
65-72 223
Аннотация
Numerous examples from various regions (easterm margin of the USA, Puerto-Rico, south-east of Africa, arctic shelf, continental margins of Israel and Bulgaria) illustrate influence of originally subaerial relict landforms of various origin on sediment transport over the shelf. Submerged river valley mostly make obstacles to longshore sediment transport, while relict coastal forms, such as beach ridges and dunes, impede transversal sediment flows.
73-79 235
Аннотация
Analysis of geology and geomorphology together with calculations of wind and wave energy enabled to define types of the Pechora Sea coasts and to determine directions of sediment transport. 10 morphodynamic regions have been identified, based on dynamic characteristics and the coast morphology.
80-93 202
Аннотация
Modern relief of the steppe zone is subject to imposed process of natural and man-induced wind erosion. Chernozems and chestnut soils of the steppes are potentially prone to destruction by wind to a different degree which may be attributed to their genesis. While dust storms occur at about the same frequency, soils of European steppes are much more actively eroded, which may be explained by specific features of atmospheric circulation. Modern semiarid belt of the continental sector in Eurasia may be considered as an area of active wind erosion of the surface, with products of erosion being involved in global migration of matter.
94-103 189
Аннотация
The paper considers problems of planation surfaces in Alpine mountains from the standpoint of abrasion-strati-graphic concept of the relief planation, as developed by the author. According to the concept, origin of planation surfaces is associated with abrasion activity of marine basins, the age and number of the surfaces being related to age and quantity of transgressive unconformities in lithofacies. In the light of the new ideas, the author recognizes 7 surfaces of planation in the Lesser Caucasus dated to interval beginning with Oxfordian-Tithonian and ending at Late Pliocene-Pleistocene.r
94-103 64
Аннотация
The paper considers problems of planation surfaces in Alpine mountains from the standpoint of abrasion-strati-graphic concept of the relief planation, as developed by the author. According to the concept, origin of planation surfaces is associated with abrasion activity of marine basins, the age and number of the surfaces being related to age and quantity of transgressive unconformities in lithofacies. In the light of the new ideas, the author recognizes 7 surfaces of planation in the Lesser Caucasus dated to interval beginning with Oxfordian-Tithonian and ending at Late Pliocene-Pleistocene.r

Юбилеи

Рецензии

Хроника

Потери науки



ISSN 0435-4281 (Print)