The Journal of Geology 

About: The Journal of Geology is an academic journal published by University of Chicago Press. The journal publishes majorly in the area(s): Zircon & Metamorphism. It has an ISSN identifier of 0022-1376. Over the lifetime, 6556 publications have been published receiving 269520 citations. The journal is also known as: Journal of Geology & The Journal of geology.

A Scale of Grade and Class Terms for Clastic Sediments

Abstract: In no other science does the problem of terminology present so many difficulties as in geology. With the growth of knowledge in any field of investigation, men devise new terms or redefine old ones in the attempt to convey more precise and definite ideas. In all the branches of science much confusion has followed the redefinition of old terms because of the indiscriminate use of the terms both in the old and the new senses. But in geology, difficulties of this kind are peculiarly great. Because geology is a field science and has followed in the footsteps of exploration, it has acquired terms from all parts of the world. Many of the names for the less common special features have come from the dialect or colloquial speech of that part of the world where they are best developed. With the use of these terms of geologists of other regions, much irregularity of usage and hence much confusion has arisen. Since '917, the writer had been engaged in the study of abrasion and shaping of cobbles and pebbles by the action of running water. In the course of this study the loose usage of cobble, pebble, and related terms (in which his own practice was no exception) has impressed him with the need of greater uniformity of usage and

World-Wide Delivery of River Sediment to the Oceans

Abstract: New data and new estimates from old data show that rivers with large sediment loads (annual discharges greater than about $15 \times 10^{6}$ tons) contribute about $7 \times 10^{9}$ tons of suspended sediment to the ocean yearly. Extrapolating available data for all drainage basins, the total suspended sediment delivered by all rivers to the oceans is about $13.5 \times 10^{9}$ tons annually; bedload and flood discharges may account for an additional $1-2 \times 10^{9}$ tons. About 70% of this total is derived from southern Asia and the larger islands in the Pacific and Indian Oceans, where sediment yields are much greater than for other drainage basins.

Geomorphic/Tectonic Control of Sediment Discharge to the Ocean: The Importance of Small Mountainous Rivers

Abstract: Analysis of data from 280 rivers discharging to the ocean indicates that sediment loads/yields are a log-linear function of basin area and maximum elevation of the river basin. Other factors controlling sediment discharge (e.g., climate, runoff) appear to have secondary importance. A notable exception is the influence of human activity, climate, and geology on the rivers draining southern Asia and Oceania. Sediment fluxes from small mountainous rivers, many of which discharge directly onto active margins (e.g., western South and North America and most high-standing oceanic islands), have been greatly underestimated in previous global sediment budgets, perhaps by as much as a factor of three. In contrast, sediment fluxes to the ocean from large rivers (nearly all of which discharge onto passive margins or marginal seas) have been overestimated, as some of the sediment load is subaerially sequestered in subsiding deltas. Before the proliferation of dam construction in the latter half of this century, rivers...

Empirical Correction Factors for the Electron Microanalysis of Silicates and Oxides

Abstract: Given suitable correction factors, the use of pure oxides and binary oxide phases as standards would make electron microanalysis independent of chemical analyses and problems of sample inhomogeneity. Ziebold and Ogilvie (1964) have shown that the calibration curve in a binary metal alloy system can, within the variance of data points, be described by the linear expression $$C_{A}/K_{A} = \alpha_{AB} + (1 - \alpha_{AB})C_{A}$$, where $$C_{A }$$ is the concentration of element A in alloy Ârelative to pure A, and $$K_{A}$$ is the background-corrected intensity of a characteristic radiation line of A in the alloy relative to that of pure A. This linear variation of the correction factor with composition can be extended to multicomponent systems by using the weighted average of the binary correction factors. Correction factors have been determined empirically for characteristic lines of ten major elements (Na, Mg, Al, Si, K, Ca, Ti, Cr, Mn, and Fe) in the corresponding oxides using phases on binary and pseudob...

Magnitude and Frequency of Forces in Geomorphic Processes

Abstract: The relative importance in geomorphic processes of extreme or catastrophic events and more frequent events of smaller magnitude can be measured in terms of (1) the relative amounts of "work" done on the landscape and (2) in terms of the formation of specific features of the landscape. For many processes, above the level of competence, the rate of movement of material can be expressed as a power function of some stress, as for example, shear stress. Because the frequency distributions of the magnitudes of many natural events, such as floods, rainfall, and wind speeds, approximate log-normal distributions, the product of frequency and rate, a measure of the work performed by events having different frequencies and magnitudes will attain a maximum. The frequency at which this maximum occurs provides a measure of the level at which the largest portion of the total work is accomplished. Analysis of records of sediment transported by rivers indicates that the largest portion of the total load is carried by flow...