The Two-Point Covariance Function of Galaxy Clustering for Extreme Values of its Argument

The two-point covariance function of galaxy clustering is discussed for small and large values of its argument.     

Positions of extragalactic objects in the vicinity of M3 and M31 (5C3 radio field) and in the 5C1 radio field

We have determined the positions of 65 compact extragalactic objects with magnitudes between 16^m and 21^m.7. The mean error of one position is about 0″.3 in α cos δ and in δ. Some hitherto unpublished redshifts are also listed.     

Regional variations in cleavage and fold development in North Wales

The arcuate pattern of the main Caledonian cleavage and associated fold axial plane traces in North Wales is due partly to NW-SE compression with tectonic transport to the southeast against the concealed crop of the Tan y grisiau Microgranite. Low-angle cleavage close to the microgranite is shown to be a local variant of the regional cleavage formed during the main deformation and not an earlier phase as previously supposed. Transcurrent movements along several major fault systems are also related to compression around the microgranite and the Harlech Dome block.     

Photometric and Spectroscopic Study of the Variable Star ET And

The short-periodic spectroscopic and photometric variations and the frequency ratio of 1:2 suggest the existence of a triple system for ET And, though some serious difficulties continue to exist in explaining all observational facts. Assuming a triple, the observable star is the primary of a very close, ellipsoidal binary system. Under this assumption the star cannot be a main-sequence B9 star as usually assumed. It should be a star located in the domain of the horizontal branch stars in the HR diagram possessing a thin and expanding envelope. Spektroskopische und photometrische Beobachtungen des variablen Sterns ET And wurden in den Jahren 1981/82 ausgeführt. Zusätzlich zu der bekannten periodischen Variation der Radialgeschwindigkeit von 48.308 Tagen, hervorgerufen durch einen Begleiter und der wahrscheinlich von der Rotation des Sterns herrührenden photometrischen Periode von 1.61883 Tagen, existieren weitere periodische Variationen. So variieren die Radialgeschwindigkeiten mit einer Periode von 0.1989 Tagen und die photometrischen Werte mit der Hälfte dieses Wertes, d. h. mit 0.0994 Tagen. Die Minima der Helligkeit koinzidieren mit den Extrema der Radialgeschwindigkeiten. Die Radialgeschwindigkeitskurve weicht etwas von der Harmonischen ab; die Werte steigen rascher an, als sie abfallen. Das gleiche Verhalten liegt auch für den entsprechenden Teil der Lichtkurve vor. Die kurzperiodischen spektroskopischen und photometrischen Variationen und das Frequenzverhältnis 1:2 legen die Existenz eines Dreifachsystems für ET And nahe, obwohl für die Erklärung aller Beobachtungswerte einige ernste Schwierigkeiten fortbestehen. Vorausgesetzt der Stern sei ein Dreifachsystem, dann ist der beobachtete Stern die Hauptkomponente eines sehr engen ellipsoidalen Systems und kann nicht ein Hauptsequenz-B9-Stern sein, wie allgemein angenommen wird. Vermutlich handelt es sich bei ET And um einen Vertreter der Gruppe der Horizontalsterne im HR-Diagramm, welcher noch eine dünne, expandierende Hülle besitzt.     

Two-Color Observations of AM Her

Observations and light curves of the variable star AM Her observed in the b and v proper color system of the Abastumani two-channel photometer are presented.     

An equable glaciopluvial in the West: Pleniglacial evidence of increased precipitation on a gradient from the Great Basin to the Sonoran and Chihuahuan Deserts

Dated macrofossil evidence documents the widespread occurrence of woodland in what are now desert lowlands of southwestern North America from the last pleniglacial (ca. 20,000 yr B.P.) to late glacial/Holocene transition (12,000–8000 yr B.P.). The composition of the Pleistocene woodlands indicates that they had already differentiated geographically in modern form, though immensely more extensive than today. The pinyon-juniper woodland (Pinus monophylla, Juniperus osteosperma) of the Mohave Desert province had not yet penetrated the central Great Basin, but extended from southern Nevada south through the vast lowlands of the Mohave and westernmost Sonoran Deserts to southeastern California and Baja California. The strongly xerophytic Mohavean woodland was characterized by a very well-marked altitudinal and latitudinal zonation with juniper-Joshua tree (Yucca brevifolia) sorting out below pinyon-juniper woodland, and with live oaks restricted to the upper level along the lower Colorado River drainage. Southeastward, the Sonoran Desert province was similarly zoned, but with the more slender-leaved Pinus edulis var. fallax as pinyon and with more live oaks in the upper zone. However, the pleniglacial woodland of the Chihuahuan Desert province was almost unzoned, inasmuch as the less xerophytic species of pinyon and live oaks prevailed over the entire span of available elevation; the pinyon was the very slender-leaved P. cembroides var. remota.The overall paleozonation indicates a strong northwest-to-southeast gradient of increasing summer rain with decreasing distance from the monsoonal source area over the Gulf of Mexico, as at present, but augmented pluvially along the same gradient. A key piece of evidence is the counterintuitive latitudinal-zonational anomaly between about 30 and 40° N in southwestern North America; the lower limits of modern vegetational zones are depressed with decreasing latitude (e.g., ca. 500 m lower at 34° than at 36° N). The axis of the gradient actually extends from northwest to southeast, paralleling the monsoonal gradient of increasing summer rain, which no doubt causes the apparent anomaly. During the Wisconsinan glacial, the latitudinal anomaly was greatly steepened, a fact requiring a pluvial increase in precipitation over the Southwest. The monsoonalpluvial pattern is supported by the Neotoma record of a northwest-to-southeast gradient of increasing diversity of evergreen oaks requiring summer rain, and by a parallel segregation of pinyon species. Equability of seasons during the last glacial is also suggested by the Neotoma macrofossil data.     

On the variability of the position of the equatorial electrojet axis in India

An examination of day-to-day and monthly mean positions of the electrojet axis in relation to the changes in the apparent solar declination, in the Indian equatorial region shows marked association between the two. For relatively quiet days, significant correlations are observed between the solar declination and each of the parameters, the northernSq focal latitude, the jet axis and the line of maximumSq(H). From the significant mutual association of these parameters, it has been suggested that the equatorial electrojet could be a part of the world-wideSq current system.     

Rio Tinto estuary (Spain): 5000 years of pollution

 Mining of massive sulfide deposits in southwestern Spain extending back to the Copper and Bronze Ages has resulted in the pollution of the Rio Tinto fluvial-estuarine complex, the site of Columbus' departure for the New World in 1492. Additional sources of potential pollution include the large industrial complex at Huelva near the lower portion of the estuary. Extensive analysis of surface sediment samples and cores has established that there are no geographic trends in the distribution of the pollutants, which include Cu, Fe, Pb, Zn, Ti, Ba, Cr, V and Co. These data have, however, demonstrated that tidal flux within the estuary carries phosphorus and perhaps other elements from the industrial complex at Huelva to the tidal limit of the system, several kilometers upstream from the discharge site. Radiometric analysis of short cores shows that sedimentation rates over at least the past couple of centuries have been about 0.3 cm/year. These data and that from a single deep core demonstrate that the estuary was polluted from mining activity long before the large-scale operations began in the late nineteenth century. Received: 3 May 1999 · Accepted: 18 October 1999     

Lower riphean low-carbonaceous shales in the southern urals: Raw material for the manufacture of porous rubble

A property of swelling on heating to yield firm lightweight granules has first been revealed for lowcarbonaceous shales (LCS) from the Riphean stratotype in the Bashkirian Megaanticlinorium, Southern Urals. These granules possess all technological properties of “keramzite” or claydite (an artificial, expanded clayey material) and can successfully substitute this material. Moreover, the procedure of their manufacture, analogous to the manufacture of “shungizite” (an artificial carbonaceous-clayey material) from Lower Proterozoic clayey rocks of Karelia, is more economical than that for keramzit. Productive beds of the homogeneous LCS make up extended bodies tens of meters thick. At the present time, they can be used as cover rocks during the exploitation of the Bakal siderite deposits. The LCS represent fine-grained quartz-chlorite-sericite aggregates (with variable relationships between the major components), bearing fine-dispersed shungite in amounts of 0.5–1.0%. High-quality raw material of this kind is characterized by a fine-dispersed admixture of a mixed-layer clayey material bearing montmorillonite and vermiculite. Geological, lithological, mineralogical, and chemical prognostic criteria have been developed for the shungizite raw material. It has been concluded that this construction material, new for the Urals, is promising for industrial use