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At least 271 records · Page 15Linked to original sources
USGS2014

United States Geological Survey records of suspended and dissolved matter in surface‐waters

Although the widest‐known and most conspicuous task of the United States Geological Survey with reference to surface‐waters has been the measurement of discharge, attention has always been given to the suspended and dissolved matter carried in them. From 1902 to 1909 the Survey published about 20 reports on the quality of surface‐waters. These reports dealt largely with stream‐pollution and its prevention, subjects that have not been included in the work of the Geological Survey since the Public Health Service began investigations of them in 1913.

Eos, Transactions, American Geophysical Union↗
USGS2014

Suspended matter in the Colorado River, 1925–1935

The rugged topography of a great part of the Colorado River Basin is a significant factor in determining the quantity of water and suspended matter carried by the River. The mountainous regions of Colorado and Wyoming contribute a large part of the flow of the River, whereas the central part of the Basin, cut by deep gorges and canyons, contributes a large part of the suspended matter carried by the River. The discharge of the Colorado River as measured near Cisco, Utah, with a drainage‐area of 24,100 square miles is slightly greater than the discharge of the largest tributary, the Green River, measured near Greenriver, Utah, with a drainage‐area of 40,600 square miles. The Green, however, carries a considerably larger load of suspended matter. Two other tributaries, the San Juan and Little Colorado rivers, each with a drainage‐area of about 25,000 square miles, carry large loads of suspended matter in proportion to their discharge. For example, the Little Colorado River in the summer of 1931 contributed less than 10 per cent of the flow of the main river at Grand Canyon, but the Little Colorado carried about 10,000,000 tons of suspended matter during this period and the main river had about 25,000,000 tons for the same period.

Eos, Transactions, American Geophysical Union↗
USGS2014

Suspended matter in several small streams

The measurement of the loads of suspended matter carried past 34 gaging‐stations located on streams in eight regional projects of the Soil Conservation Service has required greater precision in the measurement of discharge and a more intensive program for the collection of samples of suspended matter than has been found necessary by the Geological Survey in making similar measurements on the larger streams on which measurements have been made in the past. It was found early in the work that much the greater part of the annual load of suspended matter was carried in a relatively few days of high water for almost all the streams on which measurements were made. In order that these loads might be determined with reasonable accuracy it was found necessary to collect samples every hour and occasionally every half‐hour on rising and rapidly changing stages during floods. Some floods occurring at night were missed in part or entirely because the resident observer did not realize that a flood was in progress. Twenty‐four‐hour sampling programs, together with the aid of electric‐alarm systems at some stations, have made possible the collection of an adequate number of samples during most floods.

Eos, Transactions, American Geophysical Union↗
USGS2014

Dissolved mineral matter in surface‐waters

The only unpublished comprehensive Geological Survey records of dissolved matter in surface‐waters are the results obtained in the study of the Colorado River and its tributaries since 1930. The records are mainly analyses of 10‐day composites of daily samples, although there are several analyses of spot‐samples from some streams in the basin and about 4000 single determinations of chloride or sulphate in daily samples. The need for a large number of analyses is shown by the fact that during the period 1925–35 the quantity of dissolved solids in 10‐day composites from the Colorado River at Grand Canyon ranged from 226 parts per million for June 11–20, 1929, to 1889 parts per million for. September 21–30, 1934. A series of analyses covering a whole year might be misleading. The weighted averages for the different years ranged from 491 parts per million for the year ending September 30, 1928, to 960 for the year ending September 30, 1934.

Eos, Transactions, American Geophysical Union↗
USGS2014

Movement of ground‐water

The movement of water through formations having capillary openings is generally laminar and obeys Darcy's law, at least down to very low gradients. About 1000 samples tested in the laboratory of the United States Geological Survey have coefficients of permeability ranging from 0.001 to 90,000, indicating probable velocities ranging from a fraction of a foot to a few miles in a year. The Thiem field‐method gives promising results for determining permeability. Movement through sub‐capillary openings is important but poorly understood; molecular attraction of the water offers great resistance to movement or compression.

Eos, Transactions, American Geophysical Union↗
USGS1936

The diurnal fluctuation in the ground‐water and flow of the Santa Ana River and its meaning

In the time alloted for this subject it will be impossible to discuss, in its entirety, all phases of the methods used in computing the loss of water by transpiration from native plant‐life along the Santa Ana River. The results of this work are published in Bulletin 44 of the Division of Water Resources, State of California. The present paper is confined to a discussion of the diurnal fluctuations that occur in the flow of the Santa Ana River and the adjacent ground‐water. On Figure 1 have, been plotted the gage‐height records for a short period (July 5–8, 1935) for eight southern California streams. These records have been selected at random from the large number of records filed in the local office of the United States Geological Survey. Some of these streams have a large drainage‐area, others are small; some are short and steep, others flat and long. The points of measurement range from 15 to 2950 feet above sea‐level. One of the streams (Mojave River) is in the desert‐region; the others drain into the Pacific Ocean. The object of Figure 1 is to demonstrate, that the diurnal fluctuation exists and is, to a large degree, similar at most points of measurement. As a rule, the maximum discharge occurs about 10 o'clock in the morning, and the minimum late in the afternoon. It is readily recognized that these fluctuations are in the main caused by the evaporation and transpiration‐loss in or adjacent to the stream‐channel.

California↗
USGS2014

Extension of normals by precipitation‐data and by comparison with another stream

The factors affecting relationship between precipitation and consequent runoff are multitudinous and their interrelation is exceedingly complex. They vary widely from time to time and place to place. Basic data are meager and the weight to be given to any single factor is usually uncertain. Runoff‐characteristics of drainage‐areas within the same region will frequently be quite dissimilar. Under these circumstances no one should hope to answer conclusively paragraph V(a) of the questionnaire submitted January 4, 1935 by the Conference.

Eos, Transactions, American Geophysical Union↗
USGS2014

On the estimation of temperatures at moderate depths in the crust of the Earth

The modern deep well makes it possible to determine the temperatures of the rocks to depths exceeding two miles, and the rock‐samples obtained at these great depths enable the geologist to estimate the depths to the deeply buried basement‐rocks to a rather high degree of precision. The latter estimates are now being supplemented to a certain extent by the precision‐measurements of geophysicist, so that reliable data seem to be assured even in those areas in which the basement rocks are not reached by the drill. With these two sources of information at our disposal—accurate temperature‐measurements and reliable estimates or measurements of depths to bed‐rock—it should be possible to construct a rather accurate subsurface map showing the temperatures on the boundary‐surface between the sedimentaries and the basement floor. In this paper it is proposed chiefly to outline the method of procedure by making some rough calculations of the temperatures at great depths for a few locations in the United States and for one location near Carnarvon, Cape Province, South Africa.

Eos, Transactions, American Geophysical Union↗
USGS2014

Preliminary report on the North Atlantic deep‐sea cores taken by the Geophysical Laboratory, Carnegie Institution

A series, of 11 cores from the North Atlantic sea‐bottom between the Newfoundland Banks and the banks off the Irish Coast have been studied by a group of geologists of the United States Geological Survey. These cores were taken by Dr. C. S. Piggot of the Carnegie Institution's Geophysical Laboratory from the cable ship Lord Kelvin with the explosive type of sounding‐apparatus, which he designed (C. S. Piggot, Apparatus to secure core‐samples from the oceanbottom, Bull. Geol. Soc. Amer., v. 47, pp. 675–684, 1936). This preliminary report is based largely on the results obtained by M. N. Bramlette, who studied the lithology, and Jos. A. Cushman, who studied the forarainifera. The geographic position, the depth of water at each station, and the length of core obtained are given in Table 1. ©1937. American Geophysical Union. All Rights Reserved.

Newfoundland and Labrador↗
USGS2014

Amygdales in Columbia River lavas near Freedom, Idaho

Incomplete study of seven amygdales from the Columbia River lava‐flows along Slate Creek, a tributary of Salmon River, near Freedom in north‐central Idaho, reveals that these small objects are of unusual geological and mineralogical interest. This paper includes an outline of the geology of the area from which the amygdales came, a description of the amygdales, and a brief account of the periodic tilting of a large fault‐block as revealed by them. Slate Creek enters Salmon River near the eastern border of the Columbia Plateau. In this locality the thick Lower Middle Miocene lava‐flows of the plateau country are interbedded with the sediments of many local lakes formed periodically as successive flows dammed the streams flowing westward from the higher country to the east. A section measured near the mouth of Slate Creek shows the volcanic rocks there to be 2600 feet thick. At some places on the Plateau farther from its borders the flows aggregate more than twice that thickness.

Eos, Transactions, American Geophysical Union↗
USGS2014

Extraordinary topaz‐replacement body in the Brewer Mine, South Carolina

A large body of massive topaz forms a part of the gold‐bearing lode at the Brewer Mine, South Carolina. This gold‐mine was opened 100 years ago and merits the distinction of being one of the early gold‐discoveries of the Southern Appalachian Region. The Brewer Mine is located near Jefferson, in Chesterfield County, near the northern boundary of South Carolina, and on the eastern edge of the Piedmont Province. The country rock is described by J. T. Pardee and C. F. Park, Jr., (Gold‐deposits of the Southern Appalachians, U. S. Geol. Surv. Prof. Paper, in preparation) as a quartz‐sericite schist that locally preserves the structure of a fine‐grained, waterlaid tuff, probably a rhyolite,from which it was derived. Exposures of granite that intrude the schist appear on the north and west at distances of a mile to a mile and a half.

South Carolina↗
USGS2014

Mode of igneous intrusion in La Plata Mountains, Colorado

The La Plata Mountains, in southwestern Colorado, have long been known as an example of a mountain group of the laccolithic type, although it has been recognized that the igneous geology was much more complex than that of typical laccoliths. A restudy of the ore‐deposits of the District, now in progress, has thrown new light on the mode of intrusion of the igneous rocks (E. B. Eckel, Resurvey of the geology and ore‐deposits of the La Plata Mining District, Colorado, Proc. Colorado Sci. Soc, v. 13, No. 9, pp. 508–546, 1936). The Mountains, which include parts of La Plata and Montezuma Counties, are 8 to 18 miles northwest of Durango and occupy an oval area 10 to 15 miles in diameter. The altitude ranges from about 8000 to 13,225 feet above sea‐level. ©1937. American Geophysical Union. All Rights Reserved.

Colorado↗
USGS2014

The problem of the Chelmsford, Massachusetts, Granite

The Chelmsford granite is quarried in and around Oak Hill, about six miles west of Lowell, Massachusetts. The granite‐area is about eight miles long and one to three miles wide, and its longer dimension has a northeast bearing which is parallel with the regional axis of foliation in the country rock. The writer favors a hypothesis that much of the granite represents granitization of biotite schist under hydro‐magmatic invasion, and under stress that was insufficient to deform or distort the preexisting country rock‐structures to any marked degree. Banding of the granite is due chiefly, to variable amounts of biotite. The bands are thin and remarkably uniform. The banding, attitudes of schist inclusions, and distribution of the entire mass con form to the regional structural elements. Lit‐par‐lit injection‐bands are not clearly discernible although many of the light‐colored bands are doubtless of such origin. The absence of flow‐schlieren is noted. Petrographic evidence shows a remarkable amount of metasomatic fabric. Undoubted primary granitic texture is practically wanting. There is a high degree of orientation of biotite, muscovite, and groups of small mosaic quartz‐grains. The contacts of inclusions with adjacent granite‐bands are very irregular and interpenetrative, and granitic material also penetrates intricately along schistosity planes within the inclusions. Large irregular feldspar porphyroblasts and strings of such grains are distributed through the inclusions, generally with decreasing concentration toward the centers. Pegmatite and quartz veins, some of which carry much tourmaline, are abundant in some of the quarries. Crystallization zoning of feldspars is very rare. Feldspars are of three generations: (1) Early polysynthetically twinned porphyroblasts and irregular groundmass grains of oligoclase or albite‐oligoclase; (2) microcline and orthoclase, chiefly as porphyroblasts, and in part replacing the earlier plagioclase; and (3) albite and albite‐oligoclase, untwinned and mottled, as individual crystals, streaks, patches, and porphyroblasts, replacing microcline, quartz, and mica. Incomplete twinning, corrosion‐contacts, optical anomalies, inclusions of minerals, pseudo‐perthitic and myrmekitlc grains are among the diagnostic petrographic features that contribute to the theory of replacement.

Massachusetts↗
USGS2014

Report of the committee on glaciers, 1936–37

The Committee was enlarged during the past year by one more member, Prof. J. E. Church of Reno, Nevada, Chairman of the Committee on Snow, who agreed to serve on it while the Chairman of the Committee on Glaciers in turn accepted membership on the Committee on Snow. Thus the two Committees, whose spheres of work are in some respects intimately related, have been brought into closer touch with each other. Although the Committee on Glaciers has assembled considerable data on different lines of glaciologic research during the past few years, it seems best to confine this report, like the preceding ones, to a record of the variations—advance or recession—of glaciers in the continental United States and Alaska, and to reserve the other data for presentation later, in separate papers. The variations of glaciers here reported are for the 12‐month period from the autumn of 1935 to the autumn of 1936.

Eos, Transactions, American Geophysical Union↗
USGS2014

Report of the committee on runoff, 1936–37

Since the last meeting of the Section of Hydrology there has been a change in the organization and membership of some of the research‐committees, one relating to rainfall, of which Merrill Bernard is Chairman, and one relating to runoff, were created to replace the one committee which had functioned heretofore on both rainfall and runoff. This action by the officers provides for greater participation of the members of the Section in committees, and is a step well worth while. The personnel of the Committee as of May 1, 1937, is as follows: H. K. Barrows R. W. Davenport I. E. Houk F. T. Mavis F. F. Snyder M. M. Bernard R. S. Goodridge W. G. Hoyt A. F. Meyer H. C. Troxell E. S. Cullings R. E. Horton Joseph Jacobs C. R. Pettis C. O. Wisler I consider it an honor to act as Chairman of the Committee on Runoff but regret, however, that I have been unable as yet to coordinate thoroughly the work of the Committee or to inform myself adequately on many runoff‐experiments and research‐problems. Consequently, my report will be very brief and informal.

Eos, Transactions, American Geophysical Union↗
USGS2014

Report of the committee on underground waters, 1936–37

In accordance with the by‐laws of the Section, the Committee on Underground Waters has been reconstituted during the past year. With their research interests turning to other subjects, several members have dropped out, and four new men have been appointed. In order to maintain contact with the work of related committees, Charles H. Lee, Chairman of the Committee on Absorption and Transpiration, and C. S. Howard, Chairman of the Committee on Cnemistry of Natural Waters, have become members of the Committee on Underground Waters. The personnel of the Committee is as follows: H. F. Blaney C. S. Howard M. M. Leighton H. E. Simpson G. M. Fair F. H. Lahee O. E. Meinzer A. C. Swinnerton Willard Gardner C. H. Lee A. M. Piper D. G. Thompson, Chairman.

Eos, Transactions, American Geophysical Union↗