摘要:

Mobility spectrums of large ions were measured during 1963 at a semidesert site near Socorro, New Mexico. The apparatus was a concentric aspirated condenser having a two‐section central electrode. The spectrums were found generally to be rather flat, with some tendency for an increasing concentration toward lower mobilities, down to the limit of observation—4.2×10−5cm2volt−1sec−1. This tendency was especially marked in the daytime. Ion groups sometimes appeared, but the existence of generally preferred values of mobility seems unlikely. In one particular ion group, the mobility apparently shifted with time toward lo

ISSN:0148-0227    

DOI:10.1029/JZ069i016p03309

年代:1964

数据来源: WILEY

摘要:

Winter precipitation is defined as rain, dry fallout, and bulk precipitation—the last being a mixture of the other two. The division of winter precipitation into phases is based on collection procedures. Each phase shows distinctive characteristics of chemical composition. Rain displays the strong influence of the nearby Pacific Ocean and San Francisco Bay. Dry fallout, collected between rains, shows strong effects from locally derived materials in the atmosphere. Bulk precipitation shows, in chemical composition, the expected blending of the two environmental influences and is about 4 to nearly 10 times higher in mineral concentration than rainwater is. Bulk precipitation is considered the geochemically significant phase that should be used in studies relating contributions of atmospheric salts to surface‐ and groundwater supplies, to weathering, and to the nourishment of growing plants. Comparison with published data indicates that, wherever sampled, bulk precipitation contains more dissolved mineral content than rainwater does. Detailed comparisons, however, are not feasible because of widely differing procedures in sampling and analysis used in various studies. Increasing attention should be given to minor constituents in precipitation, as well as recognition of the several phases of precipitat

ISSN:0148-0227    

DOI:10.1029/JZ069i016p03319

年代:1964

数据来源: WILEY

摘要:

An analysis is presented of water transport calculated from the electric potential measurements obtained on two electrode systems operated from 1953 to 1958. Direct current observations and acoustical current measurements provide empirical calibration data for the electromagnetic systems. Mean volume transport calculated for a 46‐km section of the eastern Bering Strait is north at 1.46±0.74 (average monthly deviation) ±0.27(average seasonal deviation)×106m3/sec for the period August through November. Although these months exhibit a long‐term predominantly northward transport, from more limited measurements the net transport during the other months of the year are likely to be either north or south and of similar magnitude. Data and calculations indicate that winds over the broad shallow northern and southern sea approaches to the strait and the atmospheric pressure distribution can produce variations in the slope of the sea surface capable of qualitatively accounting for the fluctuations observed in the average current. Tidal current oscillations superimposed on the net flow vary from 0.15 to 1.00 m/sec but do not contribute greatly to net transport either in magnitude or direction. Variations of sea water temperature reflect net transport fluctu

ISSN:0148-0227    

DOI:10.1029/JZ069i016p03335

年代:1964

数据来源: WILEY

摘要:

Measurements made in January 1963 at Lake Bonney, Antarctica, showed that the maximum water temperature was about 7.5°C at a depth of 10 to 15 meters. Measurements of density, electrical conductivity, and chloride content indicated that the water was stratified and stable. The absorption length for solar radiation was 8.2 meters. It is concluded that the primary heat source was solar radiation

ISSN:0148-0227    

DOI:10.1029/JZ069i016p03355

年代:1964

数据来源: WILEY

摘要:

An approximate method for predicting water table fluctuations caused by a variable recharge is presented. It is assumed that the drains are at the water table, and that the drained permeable stratum is deep, homogeneous, and isotropic. The main approximation of the flow system is the linearization of the boundary condition on the free surface. In this way the problem is reduced to the solution of a Volterra integral equation of the first kind, which is solved by a numerical technique. The results are presented in a dimensionless form in tables and graphs.

ISSN:0148-0227    

DOI:10.1029/JZ069i016p03361

年代:1964

数据来源: WILEY

摘要:

A solution is given to the problem of the steady flow of precipitation to an infinite series of tile drains above an impervious layer. The free surface boundary conditions are exactly satisfied, but the shape of the impervious layer is approximated. Capillary forces are neglected. The theoretical results are compared with limited field measurements, and good agreement is found. The solutions become less accurate when the drains are very close to the impervious layer. The limiting casss are shown.

ISSN:0148-0227    

DOI:10.1029/JZ069i016p03371

年代:1964

数据来源: WILEY

摘要:

Dupuit's formula for the discharge from a well in a homogeneous aquifer is generalized for aquifers with horizontal or vertical layers of different thickness and conductivity and also for aquifers in which the conductivity varies continuously with the depth.

ISSN:0148-0227    

DOI:10.1029/JZ069i016p03383

年代:1964

数据来源: WILEY

摘要:

Analyses of data from lysimeters and small watersheds near Coshocton, Ohio, indicate the effects of various soil and agronomic factors on the magnitude of the several elements of the water budget. From lysimeter data, the effects of soil types and agronomic practices upon the magnitude of evapotranspiration (ET) are shown for corn, wheat, and meadow in a 4‐year rotation. From small‐watershed data, the magnitudes ofETfrom various parts of the profile of Muskingum soils with covers of corn, pasture, and woods are indicated. Data for a 5‐year period showed that, on similar soils, areas with a cover of shallow‐rooted poverty grass had greater percolation and runoff, and lesserETand water‐use efficiency, than areas with a cover of deep‐rooted birdsf

ISSN:0148-0227    

DOI:10.1029/JZ069i016p03387

年代:1964

数据来源: WILEY

摘要:

Data, in large part collected since World War II, allow a recalculation of the rates of regional erosion in the United States. These data indicate a rate of denudation for the United States as a whole of 2.4 in./1000 years, or about twice that of older estimates. The most rapid rate, 6.5 in./1000 years, is recorded from the Colorado drainage. The slowest rate, 1.5 in./1000 years, is found in the Columbia basin. Other drainage areas and their rates are the Pacific slopes, California, 3.6 in/1000 years; the western Gulf of Mexico, 2.1 in./1000 years; the Mississippi River watershed, 2.0 in/1000 years; the South Atlantic and the eastern Gulf of Mexico, 1.6 in/1000 years, and the North Atlantic, 1.9 in/1000 years.

ISSN:0148-0227    

DOI:10.1029/JZ069i016p03395

年代:1964

数据来源: WILEY

摘要:

The sorting processes responsible for the development of bedding in cross‐bedded deposits were studied in a small laboratory flume. Flow separation over the foreset slope of the deposit is the primary factor responsible for the dispersion and sorting of the various grain sizes. Important sorting processes include selective transport due to differential settling velocity, pulsatory movement of particles, and dispersive pressure. The bedded structure in a foreset deposit characteristically reflects the segregation of grain sizes that occurs along the topset (backset) deposit. The reworking of the foreset slope by fluid turbulence causes small variations in grain fabric and packing that may accentuate the definition of the cross‐bedded struct

ISSN:0148-0227    

DOI:10.1029/JZ069i016p03403

年代:1964

数据来源: WILEY