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A model for climatic change, and particularly for the changes of the late Cenozoic, involves as its primary variables the albedo of the earth and the heat storage characteristics of the oceans. Geography exerts a strong influence. The model proposed does not require metaphysical causes or astronomical events other than known variations in the earth's orbit.
Aquifer diffusivity (T/S) was calculated for 10 sites in the alluvial aquifer adjacent to the Ohio River by observing the response of the aquifer to a flood wave in the river. The calculated type curves matched the observed aquifer response reasonably well at eight of the 10 sites. The diffusivities ranged from 0.4 ft 2 sec -1 to 10.3 ft 2 sec -1 and were generally in agreement with diffusivity values calculated from pump-test methods at two of the sites. Interference from pumping 1/2 mile upstream from one site and localized aquifer inhomogeneity at another site precluded calculation of diffusivity. Determining the shape of the ground-water recession curve may be difficult, but it can be done satisfactorily by collecting water-level data during an extended period of ground-water discharge and transposing the average recession curve to the flood period being analyzed. The flood-wave response method for estimating aquifer diffusivity provides a relatively inexpensive technique for obtaining a significant part of the data needed to predict the aquifer's response to river and pumping stresses.
Data gathered from monitoring activities and project studies indicate the ubiquitous occurrence and distribution of polychlorinated biphenyls in the aquatic environment. Residues have been detected in samples from 19 States, representing nearly every region of the country. Concentrations ranged from 0.1 to 4.0 ug/l in unfiltered water samples and 5.0 to 3,200 ug/kg in bottom sediments. PCB residues were also found in fish and aquatic plants. Samples were prepared by the same techniques used for general chlorinated insecticide detection, with special attention to cleanup and separation of PCB's from other compounds. Basic identification and quantification were made by dual-column electron-capture gas chromatography and confirmed by gas chromatography mass spectrometry whenever possible. The sampling program is expected to be broadened geographically in 1973 and increased in successive years in order to more adequately define the distribution of PCB residues in the major drainage basins of the United States.
High-altitude photography provides an effective method of monitoring the spatial extent of turbidity plumes in Lake Ontario. Large plumes generated by the Niagara, Genesee, and Oswego Rivers are identifiable on photographs obtained from about 60,000 feet above the lake on July 6, 1970, October 19, 1970, and May 29, 1971. The Niagara plume, covering as much as 43 sq mi of the lake's surface, is the largest turbidity feature. The configuration of the plumes is a function of river discharge, level of turbidity, and wind speed and direction.
A simple method is proposed for estimating the probable magnitude and frequency of streamflow that is in excess of predetermined minimum streamflows required downstream in eastern Massachusetts and southern Rhode Island. Regional curves relate these annual volumes of streamflow excess to the average annual discharge and the median 7-day annual minimum flow of the site. Use of the curves is illustrated by a hypothetical example.
Extreme changes in velocity, stage, and Manning's roughness coefficient, n , were observed during the first year after canalization of Hanging Moss Creek at Jackson, Miss. Additional changes were observed during the following 8 years. The channel, constructed during the summer of 1963, had a 50-foot-wide bottom, 2:1 side slopes, and 12-foot depth. In March 1964, average velocities of 7.8 feet per second were measured at a 5 1/2-foot depth in the clean channel and Manning's n was computed to be 0.022. In October 1964 the average velocity was 3.2 fps at a 5 1/2-foot depth and Manning's n was 0.045. The channel was then lined with fairly thick vegetation consisting of small willows, weeds, and grass. In October 1970 (summer foliage existing) the average velocity was 2.0 fps at a 5 1/2-foot depth and Manning's n was 0.07. Willow trees, 8 to 10 feet high, then lined the channel. In March 1971 (barren foliage), Manning's n was 0.05. In March 1972 (barren foliage), Manning's n was increased to 0.07. These observations indicate that the commonly used values of Manning's n for channel rectification (0.02-0.03) are low and that the carrying capacity of earthen channels may be reduced 50 percent as a result of only 1 year's growth of vegetation and 70 percent as a result of 8 year's growth. The carrying capacity during summer foliage is approximately two-thirds the carrying capacity during barren winter foliage.
The sequence of mid-Cenozoic volcanic events in the western San Juan Mountains is closely analogous to that elsewhere in the San Juan volcanic field. The Lake Fork, Picayune, and San Juan Formations were erupted from a cluster of central volcanoes from 35 to 30 m.y. ago, when dominant activity shifted to more silicic ash-flow eruptions with accompanying caldera collapses. The Uncompahgre and San Juan calderas, each about 20 km across, formed mainly from eruption of the 28-m.y.-old Sapinero Mesa Tuff. Collapse occurred concurrently with eruption, and intracaldera tuffs accumulated to a thickness of more than 700 m. Both calderas were resurgently domed together; the northeast-trending Eureka graben formed along the distended crest of that dome. The Uncompahgre caldera was then flooded by several 27- to 28-m.y.-old ash-flow sheets from easterly sources, and also by one apparently erupted from the Silverton caldera nested within the older San Juan caldera. The Lake City caldera, located within the older Uncompahgre caldera, formed about 22.5 m.y. ago in response to eruption of the Sunshine Peak Tuff.
Six samples of group C eclogites from California and southwestern Oregon have initial Sr 87 /Sr 86 ratios in the range of 0.7028 to 0.7051; Rb contents from less than 1 to 53.4 ppm; and Sr contents from 147 to 270 ppm. These data and major-element compositions suggest that the eclogites were derived from basalts older than but similar in composition to those intercalated with Mesozoic cugeosynclinal sedimentary rocks in California and western Oregon. The isotopic heterogeneity of the eclogites and associated graywackes contrasts with a uniformity of Sr 87 /Sr 86 in many younger calc-alkaline volcanic rocks of the circum-Pacific province. Derivation of the younger volcanic rocks from an eclogite-blueschist melange isotopically similar to those investigated here would require isotopic homogenization or integrated partial melting over sufficient volumes so as to reduce these variations in the derived melts.
The amount of water and sulfur in pumice erupted during periods of vigorous activity during the 1969-71 Mauna Ulu eruption varied inversely with fountain height because of degassing during the fountaining. The pumice lost about 0.05 wt percent water and 0.003 wt percent sulfur during fountaining to heights of 400-540 m. Analyses suggest that the initial volatile content of Mauna Ulu lava was greater immediately preceding periods of high fountaining than during weak activity between those periods or after the last high fountains on December 30, 1969. Water and sulfur were systematically depleted during nearly isothermal flowage in lava tubes. Rapidly quenched samples of dipped melt show losses of about 0.03-0.04 wt percent water and 0.007-0.008 wt percent sulfur during flowage for several hours through a distance of 12 km. Glassy skins on cooled pahoehoe flows contain about 0.002-0.003 wt percent less sulfur than quenched melt at comparable distances from the vent, because of continued degassing under natural cooling conditions. Chlorine shows similar but less well defined trends. Pumice erupted in high fountains becomes more strongly oxidized than the parent magma, because of mixing with air while still at high temperatures.
Uranium, thorium, and potassium contents were determined in 94 samples of drill cuttings from a 9,774-foot-deep exploratory hole drilled entirely in crystalline schists of the basement complex of the Yukon-Tanana Upland. The data indicate two distinctively different rock types and reflect differences in the calcite content of the rock. Zones of anomalously high concentrations of the radioelements probably reflect the effects of the emplacement of the nearby Eielson pluton.
Volcanic rocks in the vicinity of the massive sulfide deposits at the United Verde mine, Jerome, Ariz., have been modified in several periods of hydrothermal alteration and greenschist metamorphism. Chlorite, 2M, mica (sericite), and epidote are characteristic alteration products. Microprobe analyses for sericite, chlorite, and epidote are recalculated to structural formulas by the method employing oxygen anion equivalents. The sericite has the general composition of muscovite, but is moderately phengitic, and two samples have 6-12 percent paragonite in solid solution. Most of the chlorite is ripidolite with approximately one-third of the tetrahedral sites filled by aluminum; octahedral aluminum slightly exceeds tetrahedral. Fe:Fe+Mg+Mn ratios range from 0.34 to 0.66; low values are associated with sulfide minerals; higher values occur in a sample peripheral to the massive sulfide deposit. The epidote is a solid solution of 70 percent epidote, 30 percent clinozoisite.
An atomic absorption spectrophotometric method has been developed for the determination of seven metal ions in the hydroxylamine extract of soils and sediments. Mn, Fe, and Zn are directly determined in the aqueous extract upon dilution. Co, Ni, Cu, and Pb in a separate aliquot of the extract are chelated with APDC (ammonium pyrrolidine dithiocarbamate) and extracted into MIBK (methyl isobutyl ketone) before determination. Data are presented to show the quantitative recovery of microgram levels of Co, Ni, Cu, and Pb by APDC-MIBK chelation-extraction from synthetic solutions containing as much as 2,000 ug/ml (micrograms per milliliter) Mn or 50 ug/ml Fe. Recovery of known amounts of the metal ions from sample solutions is equally satisfactory. Reproducible results are obtained by replicate analyses of two sediment samples for the seven metals.
The generic names Archaeocycas and Phasmatocycas are introduced for two previously announced but unnamed new genera of Early Permian plants; these taxa are regarded as early stages in the cycadean lineage. The names arc formalized with diagnoses, illustrations, and type designations.
Fossil pollen was recovered at Tahoe City, Calif., from beneath a 1.9-m.y.-old volcanic flow. Pollen counts of four fossil samples are compared with soil-surface pollen samples from the Sierra Nevada. The presence of Picea (spruce) pollen in the fossil samples suggests that summer drought conditions in the central Sierra Nevada were less severe prior to 1.9 m.y. ago than they are now.
Trachyscaphites pulcherrimus , described originally by Ferdinand Roemer in 1841 from fragments of nodose ammonites from Germany, is characterized by having five rows of tubercles on each flank of the phragmocone and three to five rows on each side of the body chamber. Weak midventral tubercles are present on some specimens. Ribbing is dense and usually irregular. The species has been recorded from upper Campanian rocks in Germany, Austria, France, Poland, and Russia. Recently a few specimens have been found at the top of the Wenonah Formation of New Jersey and in the Taylor Marl of Texas.
A procedure has been devised for the fractionation of humic acid samples from different environments. This procedure involves fractionation of the sample by adsorption chromatography on a Sephadex G-50 column followed by chromatography on either a G-25 or a G-100 column. The fractions of the solutions are then examined by small angle X-ray scattering. Three different types of behavior have been detected among the humic acid fractions: (1) Some fractions show very little change in aggregation at pH values above 3.5. (2) One fraction forms aggregates at pH values above and below pH 7, but at pH 7 it is completely dissociated. (3) In some fractions the degree of aggregation decreases with increasing pH. However, even at pH values as high as 11.5 some large particles are still present. These differences in association behavior are due to the interaction of different attractive and repulsive forces. In many aggregating systems only one type of attractive force is dominant; however in humic acid systems hydrogen bonding, π bonding between planar aromatic moieties, and other coulombic interactions apparently all play a role in the formation of molecular aggregates.
A relationship is established between fluorescent spectra obtained by using a light path through the liquid solution and the fluorescent spectra obtained by a direct reading of surface reflection (remote sensing). A brief review of quantum fundamentals provides the necessary information to conclude that "see-through" and reflectance spectra are identical in wavelength response. Many floating films contain fluorescent materials; thus fluorescent spectroscopic techniques were used to obtain the fluorescent spectra of lube oil, crude oil, and lignosulfonie acid in an effort to detect, identify, and quantify these representative fluorescent materials in water solutions. For each material tested the emission maximum was established. The emission maximum was then held constant while the absorption spectrum was recorded and the absorption maximum established. The complete spectral curves are presented.
Problems of underground storage of waste involve geology in its broadest sense, including hydrology, geochemistry, and geophysics. Wastes may be solid, liquid, or gaseous, and they may be chemically toxic or noxious, esthetically offensive, or radioactive. Some wastes require only temporary containment, whereas others must be isolated for indefinitely long periods. The means and locale for emplacement underground depend upon many governing geological factors, including the physical, chemical, hydrological, and hydraulic properties of the host formation. These must be studied relative to the physical, chemical, and thermal properties of the waste and of potential interactions between the waste and the host formation. Thorough knowledge is essential because lack of it may lead to undesirable or disastrous environmental consequences. Escape of waste may contaminate the surface or near-surface environment; it may destroy the usefulness or accessibility of resources such as ground water, petroleum, and minerals. Effective management of underground waste requires adaptation of current technology and development of new technology.