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The form and character of solifluction lobes in the Ruby Range, Yukon Territory suggest the outlines of a developmental cycle. Small lobes have relatively steep narrow fronts, and late snow melt areas that are completely vegetated, with few rocks. Large lobes have gentler wider fronts, and late snow melt areas that are bare and rocky with poorly developed vegetation. The difference between lobes results from increased snow accumulation in the lee as the lobe becomes larger. Increased snow melts later in the summer, plants have less time to mature, and erosion becomes more important than growth. The eventual product is a subdued system of fairly stable treads and risers. The most recent phase of development appears to have begun with the advent of neoglaciation (2800–2600 years, B.P.) at the close of the hypsithermal. [ABSTRACT FROM AUTHOR]

The relocation of the medieval East Slav state center from the middle Dnieper to the Volga-Oka region was a lateral shift within the potentially most useful agricultural land, rather than a retreat from fertile steppes into the forest. The physical geography of the Volga-Oka interfluve region around Moscow is less inviting, but similar in many respects to the middle Dnieper region around Kiev, and medieval agriculture was highly developed in both regions. The Volga-Don region developed later, but was not merely a land of hunters and herders when political power was transferred. The early Slavic settlers probably had learned about the environment from their Finnic neighbors, and a solid agricultural economy was based upon the use of light plows, for which the light soils were no great disadvantage. The economic strength of the Volga-Oka region was second only to that of Kiev, and it immediately assumed power when the latter fell. The various reasons for the particular success of the little Moscow principality within the region are reinforced by a better understanding of regional trends. [ABSTRACT FROM AUTHOR]

The attempt to reconstitute the pluvial and arid periods of Saharan Africa finds, in the Hoggar region. vestiges of what may be humid and dry periods in alternation. It is apparent that the humid periods for the lowland country derive from the extension northward of tropical conditions but that, on the other hand, the humid periods in the highlands are related to the southward spread of mediterranean climatic conditions. Evidence is presented that the Quaternary opens with a warm and humid episode during which tropical fauna extend northward and reach to fairly high elevations, which period may possibly be identified with Lower Villafranchian in the archeologic scale. A drying-out period was followed by a cooler humid period during which the higher mountains show the spread of mediterranean mountain flora (Upper Villafranchian), terminating in at least one period of wet-cool conditions making for solifluction and frost-cleaving. Middle Quaternary conditions suggest an arid period of sand dune accumulation followed by a more moist period in which a tropical fauna again extends northward (Upper Acheulian). Upper Quaternary shows an arid period followed by a short moist period in which savanna flora and fauna spread at the lower elevations and a more xerophilous mediterranean flora and fauna spread though the highlands (Moustero-Aterian). The alternation of climatic periods is not fully regular, and there are many problems remaining in the interpretation of climatic, floral, faunal, and human occupance sequences, but a progressive drying-out does seem indicated. [ABSTRACT FROM AUTHOR]

This is a study of the physiography of the Republic of Kenya. It shows that the country has a diversified landscape which so far, has not been given a serious geographical analysis. The existing physiographic maps are reviewed and found to be far too generalized to be of much practical value. a detailed physiographic map is presented based primarily on landform genesis. From the map, one can appreciate the various landscape types in Kenya as well as the forces that have produced them. Fourteen major physiographic regions are suggested, each being further sub-divided into a number of sub-regions. The final map looks complicated, but the author shows that this careful, detailed scrutiny is necessary for the deeper understanding of the physical environment. [ABSTRACT FROM AUTHOR]

The northeast shore of Tanganyika was mapped using a descriptive classification of shore zones and especially designed form. To test the effectiveness of the system as a a basis shore zone research, maps were made at three distinct scales. small-scale maps (less than 1:1,000,000) the classification and symbols provide a useful means of showing the general distribution od the classes, types, and subtype of shores. The system can be used on medium-scale maps (1:125,000,000) in sufficient detail to reveal questions, concerning processes of shore formation and so can be a useful research tool for studying shore zone topography. Large-scale maps (over 1:125,000) appear to most useful for detailed description of shore zones for local operational purposes.

This article focuses on the geographic regularities of the earth. Physical geography is the study of the distinctive characteristics of the state and development of the landscape envelope of the earth. This article is concerned with the entire landscape envelope as an integral system, studied by general physical geography. The author discusses the law of the wholeness of the landscape envelope. Another characteristic feature of the landscape envelope of the earth discussed in the article is the presence in it of systems of circulation. The system of oceanic currents forms circular movements of water rotating in a clockwise direction in the northern hemisphere and in a counterclockwise direction in the southern hemisphere.

This article focuses on contemporary research in physical geography in the Chinese people's republic. The national program of geographical research as pursued not only in the institutions subordinated to the Chinese Academy of Sciences but also in the academic schools, is presented at the congresses of the Chinese Geographical Society. The research program being earned out at present was formulated at a congress held in Peking in January 1960. This program is characterized by its close connection with the practical needs of the national economy, and the principal objective of its activities is research leading to increased agricultural production.

Discusses the coastal geomorphology of Majorca, an island in Spain. Divisibility of the large-scale morphology of the Balearic Islands to two basic structural units; Description of the physiographic characteristics of the areas; Association of cliff coasts with deeper waters offshore.

The article describes an experimental integration of lecture and laboratory in Geography I at the Southwestern College in Chula Vista, California. The main goals of the laboratory course are allowing students enough time to explore basic aspects of each topical area and letting them explore the characteristics if geographic relationships. It also includes field excursions to further explore geography.

The article discusses the basic concepts of using vegetative key in identifying plant species for the geographic research of vegetation in Los Angeles, California. This method has been used by several scientific workers during periods when many important range, turf and forest varieties were not in flower. Physical geography students with no training in botany have also studied vegetation through this technique which can be learned by a few definitions and by comparing parts of plants.

The article offers an explanatory account of central Panama's coastal features. The author states that this explanatory account is based on field observations in the summer of 1959 and on the study of available literature in the country. He describes the characteristics of Panama's coast and provides maps that illustrate his descriptions.

The article proposes a preliminary descriptive classification of shores. The author states that this descriptive classification of shores will be useful in their description and will be helpful in research. He states that this descriptive classification proposal came about due to the belief that genetic classifications are not a satisfactory means of identifying shore zones for descriptive purposes.

The article describes the physical features and topography of the Sierra Juarez and the San Pedro Martir highlands in Baja California, Mexico. Located in a fault block of crystalline rocks, these mountains contain valuable natural resources. The climate in the mountains is classified as Mediterranean. Decades ago, Indians permeated the highlands to hunt and to gather piñon seeds, and livestock herds grazed in the San Pedro Mártir. Another source of income is gold mining.

Analyzes the equation used to derive the flow velocity from antidune wavelength for open-channel conditions in cloridorme formations in Gaspe Peninsula, Quebec. Calculations based on the modified equation; Indications of a much higher flow velocity.

In Dutch sub-tidal waters, mud settling from suspension can produce a layer with a thickness of only some millimetres in one slack-water period. However, consolidated mud layers of 10–25 mm thickness in sub-tidal deposits are often observed. This indicates that mud may be preserved over several slack-water periods. This is only possible if the critical shear velocity (U∗c) for the initiation of sediment movement is not surpassed after slack water. Tube and flume experiments reveal: (1) Thicker mud layers have smaller initial consolidation rates and lower values of U∗c. (2) A higher sand content of the mud always gives a more rapid initial consolidation. The U∗c-values increase to a maximum which is reached at a sand content of 40%. Higher sand contents lead to decreasing values of U∗c. (3) For one particular mud sample the U∗c-values increase linearly with the mud concentration Of the bed material. (4) After three hours of consolidation a mud layer may carry a sharply bounded sand layer 0.5 cm thick. By application of the results of the experiments to natural conditions in tidal water some tentative explanations are possible of the formation of flaser, lenticular and sand-clay alternating bedding. [ABSTRACT FROM AUTHOR]

Relative mineral frequencies (number or weight) are not suitable to study variations in the absolute frequencies of individual heavy-mineral species in a turbidite. A particular grain size can be selected as the "nominal grain" and numbers of grains of a particular mineral in all size classes can be converted to nominal grains. The total number of nominal grains per gram of sediment sample has been defined as the "nominal grain abundance", which is a function of the volume (or weight) of the total mineral in the sample. Study of a simple, graded, Tertiary turbidite indicates that the least vertical change in heavy-mineral content occurs at, or slightly above, the middle part of the bed. Heavy minerals in the distal part of the turbidite have more uniform vertical distribution than in the proximal part. [ABSTRACT FROM AUTHOR]

Microscopical and chemical examination of intertidal flats of the Wash indicate that phases of iron corresponding to ferric hydroxide and iron monosulphide are involved in the early diagenetic formation of pyrite, the first being an important source of the iron. Sedimentological data are tested against analyses of total iron extractable by hydrochloric acid and concentrated nitric acid, and of the pyritic fraction of this iron; ignition data for residual organic matter are considered. The occurrence of the pyrite as isolated grains and spherules of framboidal texture is recorded, their size ranges given, and iron monosulphide recognised as the precursor of both forms. Ordering in the pyrite framboidal spherules is recorded and internal coalescence confirmed as a feature of primary growth which obscures the ordering. [ABSTRACT FROM AUTHOR]

A simple method to estimate the degree of ‘crystallinity’ of illite has been used for several years in three French laboratories. Many results, which are unpublished, were obtained; three examples are presented in this paper. They show the sensibility of the method, which allows one to appreciate, above all other methods, burial diagenesis, the front of metamorphism, or some regional areas of very weak metamorphism. [ABSTRACT FROM AUTHOR]

The observed size in the thin-section is less than the true train sizes of the clastic rock as the thin-section plane does not necessarily pass through the centre of gravity of the grains. Correction factors based on probability theory give corrected arithmetic moments of the size distribution in the elastic rock from the observed arithmetic moments of the size distribution in the thin-section. The corrected arithmetic moments so obtained are transformed to their equivalent corrected phi moments which are useful to generate the unknown size distribution of the clastic rock by the help of Edgeworth's series. [ABSTRACT FROM AUTHOR]

Indices based on Wentworth phi values of Q1, Md and Q3 are used for textural classification of sediments. Wentworth phi values enable a detailed subdivision. A nomenclature based on the Wentworth phi indices is developed. The indices, and to a smaller degree the names, show sorting and skewness based on integer phi units. The classification scheme gives a continuous scale from gravel to fine clay. The Q1MdQ3-indices can be used for distinction of river, marine and loess deposits. The addition of indices of the 1st and 99th percentile, giving 5-digit indices, augments the Possibilities for a determination of the environment: river deposits can be distinguished from beach and dune sediments and in more detail from shallow marine and coastal deposits. The indices can be handled by data-processing machines. [ABSTRACT FROM AUTHOR]

The crystallinity and mineralogy of both the glauconite and the clay fraction of samples from six contemporary marine environments were investigated by X-ray diffraction. In those areas where glauconite is now forming, the mineralogy and the degree of crystallinity of both the glauconite pellets and the associated clay fraction are similar. In contrast, detrital and relic glauconites are observed to have mineralogies that are different from their clay fractions. No consistent relationship was observed between degree of crystallinity and color of the pellets. Further, only two classes of glauconite as defined by BuRsT (1958) were common: expandable, interlayered clays and two or more clay minerals in a mixed assemblage. Based on the clay fraction-glauconite similarities and other supporting evidence, glauconite on the Scotia Ridge is concluded to be authigenic. Glauconite from Santa Monica Bay, California and from the continental shelf off Morocco appear to be detrital. Glauconite pellets in the shelf sediments off Guinea and the southeastern Atlantic Shelf of the United States are both detrital and authigenic. The poor crystallinity exhibited by the Chatham Rise glauconite is in contrast to the well-crystallized associated clay fraction and indicates that they are not genetically related. However, the origin of this glauconite remains in doubt. [ABSTRACT FROM AUTHOR]

Presents a comparative study of dry western littorals. Speculation about the causes for the extreme aridity; Theoretical knowledge of the atmospheric processes at work; Correlation between spatial variations of sea temperature and precipitation averages.

Demonstrates the use of stratified random sampling and statistical analysis applied to a land-use problem in Wisconsin. Objectives of the inquiry; Samples used in land use study; Implication of the results of the study to geographic research.

Focuses on the impact of the distribution of generic terms in the place-names of the Northeastern U.S. on the significant aspects of American cultural history and geography. Limitations of the study in terms of area, topic and source materials; Origin and morphological connotations of the terms; Categories for sorting out the majority of the research terms.

Focuses on the geographic cycle in periglacial regions as it is related to climatic geomorphology. Morphogenetic regions; Normal cycles.

Focuses on William Morris Davis' concepts of slope development viewed in the light of quantitative investigations. Study of slope problems.

Focuses on the place of geomorphology in the geographic sciences. Methods of teaching the elements of physical geography; Geomorphology as a part of geography.

Focuses on the methods used by geomorphologist William Morris Davis. Career history; Contributions to geomorphology; Achievements.

Profiles geomorphologist William Morris Davis. Personal background; Career history; Achievements.

Focuses on the implications of the decline of the interest in physical geography for the progress in geography in the U.S. Expansion of the field of geography; Development of geomorphology; Plan of the Geological Society of America to establish a Division of Geomorphology.

Focuses on the role of physical geography in the training of the geographer. Interests on the essentials of physical geography; Consideration on biological influences; Disciplines in physical geography.

Delves into the nature and origin of the topographic features of the Rhône Delta. Identification of the different definitions of deltas according to various scientists; Discussion of the place's regional geology; Description of the lower Rhône valley.

Examines laterite in relation to soils of the tropics by researchers from the U.S. Variance of soils in perennially hot and warm regions of low altitudes; Geographic line of division between soils of tropical regions and those of temperate climates; Control of precipitation effectiveness on the general type of vegetation.

Focuses on the quantitative and qualitative consideration of the cultural forms, identity and distribution of house types in Louisiana. Detailed analysis of several houses for classification; Assessment on the constituent elements of the individual house; General classes of the house structure.

Profiles William Morris Davis, leader in geomorphology and geography. Career development; Work in meteorology;Work in geology; Work in geomorphology; Work in other phases of geography; Professional standards.

Discusses key issues concerning the agricultural geography of Jamaica in 1932. Historical background; Physical features of the land; Climate.

Explores the physiographic divisions of the U.S. Explanations concerning the need of natural divisions; Details of the work of the Association of American Geographers; Account of the designation by professor W. M. Davis of dominant factors in topography.

The article presents various titles and abstracts of research papers related to geography by the Association of American Geographers. Some of papers included are "Problems of Geographic Influence," by Albert Perry Brigham, "Some Geographic Factors Influencing Brazilian Trade," by Walter S. Tower, "Postglacial Migrations of Vegetation in the Middle West," by Henry Allan Gleason, "Bases for Dividing the United States into Physiographic Provinces," by N. M. Fenneman, "The Losses of Nebraska," by G. E. Condra.

The article brings together certain principles of geographical description, like, physiographic topics, and ontographic topics. The nature of analytical and systematic studies of land forms in their relation to regional accounts of land forms, is discussed. The analytical and systematic studies are equally useful in other divisions of geography in preparation for regional treatment. According to the author, the description of existing landscapes, districts, and regions of the earth's surface is the goal toward which other phases of geographical study, whether presented as personal narrative, historical review, analytical discussion, or systematic arrangement, all lead.

Explores the Rocky Mountains of Colorado. Determination of the altitude of the loftiest ranges; Repeated application of the results announced for the Boulder district by the studies; Contrasts between the visits of 1869 and 1910.

The article reports that there has been increasing interest in the use of intra-individual test discrepancies as a measure of functioning efficiency. One of the major problems in estabhshing scatter patterns has been that of finding a suitable internal reference point. The three reference points most commonly employed are the mean or IQ, the vocabulary score, and the altitude or maximum score. Psychologists who believe that the G factor is an ability argue for the use of the IQ as a reference point while those who believe that it is a capacity use altitude as a reference point. In regarding intelligence as a capacity or potentiality rather than an ability, vocabulary and altitude proponents consider that test scores falling significantly below the potentiality indicate mental inefficiency or personality disorganization.