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Minerals of the alunite-jarosite, beudantlte, and plumbogummite groups can be divided on the basis of iron or aluminum content into two groups which are consistent in optical and X-ray characteristics. Both chemical and X-ray data are needed for identification.
Recent advances in flameless atomic absorption allow determinations of bismuth in concentrations as small as 50 ppb in 0.2 g of rock or soil sample. The sample is fused with sodium bisulfate and the fusion product is leached with hot 2 M hydrochloric acid and treated with ammonium citrate, (ethylenedinitrilo) tetraacetic acid disodium salt, and finally with ammonium 1-pyrrolidinedithiocarbamate to form a complex which is extracted into methyl isobutyl ketone. Aliquots of the latter are pipetted into a graphite furnace and then subjected to an established and automated program of drying, charring, and atomizing. Recorded peak heights provide a measure of the amount of bismuth present.
Equations are given for using the correlation coefficient between annual peaks at a pair of stream gaging stations to estimate the interstation correlation coefficient of estimated T -year peaks, computed standard deviations, and computed skew coefficients at the same pair of stations. The equations are based on statistics computed from samples of annual peaks simulated from normal distributions with built-in interstation correlation. The interstation correlation of 50- year peaks was found to be about equal to the square of the interstation correlation coefficient of the annual peaks.
A study in 1970 established a natural background concentration of mercury in surface water in the Adirondack region of New York. In 1974, new methods of sample preservation and analysis were used in determining concentrations of mercury of samples of water from the same surface-water sites sampled in 1970-71. Concentrations of mercury for all sites in the 1974 study were virtually the same as those obtained in 1970-71, less than 0.5 microgram per litre, which is the detection limit of the methods.
Samples of water and gas were collected from six springs and two wells in the Upper Cretaceous Great Valley sequence and Franciscan Formation underlying the Coast Range of northern California and from four oil wells penetrating Tertiary sedimentary rocks in the Kettleman North Dome oil field. Comparison of the dissolved free amino acid compositions of the waters from the two locations show overlapping ranges with many more similarities than differences. The detection of nonprotein amino acids (sarcosine, β -amino n -butyric acid, and others) indicates the protein degradation is partly chemical rather than strictly biological. Other low molecular weight degradation products (methane, ethane, nonvolatile organic acids, and other organic chelating agents) were found. This may be one mechanism for the transportation of organic matter from the source rocks to the reservoir rocks of an oil deposit.
An injection of chloride, sodium, and stable strontium was made at a constant rate for 3 hours into Uvas Creek, Santa Clara County, Calif., to determine the mass transport processes in a small stream. Five observation points were selected within a 610-metre reach of the stream below the injection site. Water samples were collected at the observation points during and immediately after the injection. A mathematical model of the stream was obtained by solving analytically and optimally the one-dimensional mass transport equation of the solutes in the stream. Comparison of field results with a simplified mathematical model indicates the dominance of convection in the behavior of sodium and chloride. The concentration of chloride and sodium can be closely simulated by the model. However, strontium cannot be well represented by the simplified model, which contains a first-order decay-type sink.
Three methods for the extraction of adenosine triphosphate (ATP) neutral dimethyl sulfoxide (DMSO), boiling tris buffer, and butanol-octanol extraction were equally effective on the alga Chlorella vulgwia . Dilution of extracted ATP samples was linear. Filtration of different volumes of samples resulted in proportional values for ATP in the extracts. Measurement of activity by either peak height or integration of the area under the peak were equally sensitive and reproducible. The assay of ATP sample was inhibited by mercuric chloride > cadmium chloride > calcium chloride > potassium or sodium phosphate, and by high concentrations of the extractant DMSO. Analysis of ATP in aquatic environments led to the problem of transferring a sample from the field to the laboratory without obtaining a change in ATP concentration. Membrane filtration of the sample followed by chilling at 4°C, slow freezing at 20° C, or freezing on dry ice were ineffective in maintaining a constant level of ATP. Chilling caused a marked increase in ATP, whereas slow freezing caused a significant loss of ATP. Freezing on dry ice was variable but generally resulted in large losses of ATP. Quick freezing by immersion of filter and algae in liquid nitrogen and storage on dry ice maintained a constant ATP level. Field extraction of the ATP followed by quick freezing in an acetone-dry-ice bath maintained the ATP in a convenient and stable form.
A gas chromatograph with a flame ionization detector was used in conjunction with a stripping chamber and cold trap apparatus to measure microgram-per-litre quantities of low molecular weight hydrocarbon gases in water samples. Glass bottles with ground-glass stoppers were used to store the samples. Formalin was added to stop bacterial activity and preserve samples with no measurable losses for as much as 7 days.
A karst topography was developed on the Madison Limestone of north-central Wyoming during the middle Meramecian early Chesterian time interval. Ancient karst features include enlarged joints, sinkholes, caves, and solution breccias that resulted from leaching of evaporitic beds in the upper 400 ft of the Madison bedrock. These features are predominantly phreatic rather than vadose. Most of the open spaces are fdled by sand and residual products reworked by the early Amsden sea, which transgressed the area during the Chesterian.
The depressions in the cone karst (Kegelkarst) of the area west of Ciales in the Lares Limestone are alined in dry valleys that have dendritic patterns. These valleys apparently record the former existence of a cover of noncalcareous clastic material that was deposited on the limestone in late Tertiary time. One system of dendritic dry valleys ends at an abandoned meander of the Rio Grande de Manati, which is about 60 m above the present floor of the river. Another system leads to large masses of "blanket sand" near the town of Florida. These valleys were apparently eroded during the late Pliocene or very early Pleistocene when sea level was at least 80 m higher than it is today.
A. proposed classification is outlined for 39 species of colonial rugose corals in 10 genera belonging to the families Stauriidae, Craspcdophyllidae (including Cylindrophyllinae new subfamily and Craspedophyllinac), Disphyllidae?, and Zaphrentidae, from the Onesquethaw and lower Cazenovia Stages in New York and adjacent areas. These corals are described or redescribed in another report now in press. Three new genera, Asterobillingsa , Grewgiphyllum , and Cyathocylindrium , are described in this report.
A simple and rapid method was developed for determining sub milligram amounts of total water in silicate and carbonate minerals. Powdered samples are fused by heating with sodium tungstate vanadium pentoxide flux in a Vycor combustion tube, and the evolved water vapor is absorbed on silica gel. After the water collection, the silica gel is heated at a controlled rate, and the released water vapor, carried by helium, is detected by thermal conductivity.
Studies of drill cores from the Catheart Mountain molybdenum-copper deposit indicate that the deposit is of the porphyry type. Hydrothermal alteration and sulfide mineralization are probably distributed in complex but systematic alteration zones. Most or all mineralization at Catheart Mountain is in a medium-fine-grained quartz monzonite enclosed within a larger mass of Attean Quartz Monzonite; no ore and little hydrothermal alteration have been seen in the Attean. Much of the ore and hydrothermal alteration seem to be and presumably are spatially related to irregular intrusive masses of porphyry. Only certain porphyry intrusives are mineral bearing, however, and many have no associated ore and alteration. Studies of hydrothermal alterations in surface exposures supplemented by rock analyses of bulk samples indicate that alteration features and sulfide zone characteristics of an area northwest of the mountain crest are, when measured against accepted porphyry models, very favorable for the occurrence of ore. Even though this favorable area has already been tested by some drilling, the presence together here of the strong center of potassic enrichment, the well-developed pyrite zone, and the strong and extensive phyllic alteration suggest that some further evaluation may be warranted.
Biotite and its alteration products (primarily chlorite) from igneous rocks around the Ray and Esperanza (Esperanza-Sierrita) porphyry copper deposits, Arizona, were analyzed for copper by electron microprobe. The copper occurs in amounts >90 p/m (limit of detection) in most of the chlorites analyzed, is concentrated at the optical and chemical boundary of chlorite and biotite, and is not associated with sulfur. Most unaltered igneous and hydrothermal biotites analyzed contain <90 p/m Cu, and except for one sample, all copper that was detected can be explained as contamination by copper from chlorite grains. The paucity of detectable copper in igneous and hydrothermal biotite and its presence in daughter chlorite suggest that the positive association noted by some workers between the proximity of an ore deposit and the copper content of biotite might be partly the result: of increased amounts of chloritization of biotite near a deposit coupled with difficulty in physically cleaning the biotite separates. Additionally, previous speculations that (1) part of the copper in a deposit may come from altered biotite, and (2) copper in biotite indicates how copper behaves in a differentiating magma, are of doubtful value if based on data derived from analyses of bulk mineral separates.
Garrelsite, NaBa 3 Si 2 B 7 O 16 (OH) 4 , originally described in 1955, has recently been reexamined by Charles Milton and Adolf Pabst and by Subrata Ghose and Horst H. Ulbrich. The latter have reanalyzed the mineral and determined the structure; the powder pattern is indexed on the basis of their 1972 cell constants. These were refined in 1973 to ɑ =14.639 A, b =8.466 A, c =13.438 A, β =114.21°, space group C 2/c. Garrelsite has been found in two drill cores penetrating the Green River Formation (Eocene) at two localities in Uintah County, Utah, and in the borate deposits of the Kramer district, Kern County, Calif. The original description of the morphology has been corrected, and the optical orientation has been redetermined.
The basal beds of the Maquoketa Shale in northeastern Iowa include a basal silty phosphorite layer that is thickest near Dubuque. In Clayton County, Iowa, the bed averages about 1 foot thick (30 centimeters) and contains 22.5 percent P 2 0 5 . Phosphatic dolomite that is 8 10 feet (2.4 3 meters) thick and occurs higher in the Maquoketa was observed only in Dubuque County. The thickest and most phosphatic rock in the Maquoketa appears to be coextensive with dark-brown shale, which also occurs mainly in Dubuque County. Rare-earth content of the phosphatic rock decreases southeastward across the area, ranging from 2,000 to about 120 parts per million. The thin low-grade phosphorite is typical of the platform-type phosphorite facies and may be' genetically related to the emergence of the Ozark uplift as an island late in the Ordovician period.
The computer program, WATEQ, calculates the equilibrium distribution of inorganic aqueous species of major and important minor elements in natural waters using the chemical analysis and in situ measurements of temperature, pH, and redox potential. From this model, the states of reaction of the water with solid and gaseous phases are calculated. Thermodynamic stabilities of aqueous species, minerals, and gases have been selected from a careful consideration of all available experimental data. The program is written in PL-1 for IBM 360 computers.
The Antictam Creek basin in the Great Valley of Maryland and Pennsylvania is underlain almost entirely by intensely folded and faulted lower Paleozoic carbonate rocks. The ground-water discharge of the basin is about 85 percent of the total discharge, in contrast with less than 70 percent of the total discharge in two small basins underlain by igneous and mctamorphic rocks in the Maryland Piedmont. Large quantities of ground water are stored in a thick residual mantle, which overlies the carbonate rocks in the valley and adjacent rnetamorphic rocks in mountain areas on the east edge of the basin. Streams that flow off the mountain areas are major sources of recharge to the carbonate-rock aquifers. Several streams lose a large part of their flow within a mile after reaching the carbonate rocks in the valley, and a few flow directly into swallow holes (sinkholes). The low density of perennial streams in the basin is a result of subsurface drainage through solution cavities along joints, faults, and bedding in the carbonate rocks. The major orientations of straight stream reaches along Antietam Creek and the strikes of major joint sets in quarries are nearly coincident, suggesting that the stream network throughout the basin is joint controlled.