Hydrochemical relationships in groundwater from central São Paulo State, Brazil

Groundwater samples from different aquifers occurring at center/northeast portion of São Paulo State, Brazil, were collected and chemically analyzed. The waters leaching Mesozoic sediments are generally more acid (pH_average=5.9) and have lower values for total dissolved solids (TDS_average=105 mg/L) than those obtained for waters leaching Paleozoic sediments of Tubarão Group. First-degree trend surfaces revealed that the deeper tubular wells occur towards east/southeast and exploit Paleozoic sediments as well fractured/fissured diabases/basalts, whereas the tubular wells in the west/northwest region are shallower. Piper diagrams indicated that the majority of the waters are a blend of waters from different lithologies. Significant correlations were found among nitrate, chloride and bicarbonate, suggesting the occurrence of some anthropogenic inputs, whereas elevated alpha activity of geogenic ²²⁶Ra indicated the need of a broad radiometric survey in the area.     

Reconstruction of the Linear Distribution of the Squared Buoyancy Frequency According to the Known Dispersion Properties of the Field of Internal Waves

We propose a method for the solution of the inverse problem of reconstruction of the vertical stratification of density in the ocean according to the known dispersion curves for internal gravity waves. For the stratification of density modeled by a linear distribution, we determine the accuracy of its reconstruction for values of the frequency of oscillations and wave numbers given with different degrees of accuracy. The posed problem is studied in the Boussinesq approximation for two traditionally used types of boundary conditions on the surface of the fluid. We deduce dispersion equations and focus our attention on their asymptotic analysis. An asymptotic solution of the inverse problem is constructed and its sensitivity to the degree of accuracy of the input data is investigated.     

Reconstruction of the space and time variability of thermohaline fields in the Sevastopol Bay

The aim of the present work is to reconstruct the space and time variability of the three-dimensional fields of currents, temperature, salinity, and density in the Sevastopol Bay under the influence of the actual external factors in 1999. For this purpose, we use a version of the numerical multilayer model on the σ-coordinates. A vast array of the data of observations accumulated as a result of regular monitoring of the Sevastopol Bay contains, in particular, the data on the sea-surface temperature measured with six-hour intervals (at the hydrometeorological station located near the center of the bay) and almost monthly vertical profiles of temperature and salinity obtained at seven hydrological stations. The comparison of the numerical results with the data of observations enables us to conclude that, in general, the model fairly correctly describes the space structure and rearrangements of the fields of temperature and salinity. Among the most important distinctions, we can mention the fact that the fresh river water penetrating into the bay is mixed with seawater faster than predicted by the model. We also discuss the causes of these distinctions. Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 23–39, September–October, 2008.     

Search for Star Groups in the Solar Neighborhood

Two methods are proposed for finding star groups in coordinate and velocity spaces, which were used to investigate stars of the Hipparcos Catalog with known radial velocities in the solar neighborhood with a radius of 125 pc. Thirteen probable nonrandom star groups in coordinate space and five moving groups in velocity space were found. These results are compared with the results of other authors.     

Spectral observations of Markaryan galaxies. II

Conclusions Since there is sufficiently detailed information on the observed galaxies listed in the notes to Table 1, we briefly summarize the main results.From the observations of 94 objects, emission lines are discovered in 64; in one, Markaryan 396, hydrogen absorption lines are observed (this is a white dwarf, probably type DA, and possibly a weak radio source [23]). In the red region there are no lines detected in the objects Markaryan 422(3), 425(3), 431(4), 433(3), 616(3), 621(5), 643(4), 655(5), 656(4), and 658(3); the number of spectrograms is indicated in parentheses; it is possible that Markaryan 643 is a galactic cluster.The objects Markaryan 595, 609, 622, 688, 699, and 700 have broad, hydrogen emission lines and can be attributed to the Seyfert class of galaxies. Markaryan 609, 622, and 699, plus, probably, Markaryan 423, possess moderate Seyfert characteristics. Furthermore, in Markaryan 414, 584, 612, 617, 646, 670, 684, and 693 broad emission lines are observed or suspected. Markaryan 586 is probably similar to a QSO. Further observations are advisable for all these objects.In conclusion, the authors express their gratitude to A. L. Shcherbanovskii for help in the treatment of the spectrograms on the M-222 computer.Institute of Astrophysics, Academy of Sciences of the Kazakh SSR. Special Astrophysical Observatory, Academy of Sciences of the USSR. Translated from Astrofizika, Vol. 12, No. 4, pp. 665–682, October–December, 1976.