An evaluation of proposed platinum group element contents in the parental magmas of the Bushveld complex

Samples collected by the authors and representing three proposed parental magmas of the Bushveld complex were analyzed for their platinum group element (PGE) contents by three different laboratories. Results differ strongly between laboratories, but imply that the parental magmas may have had flatter chondrite normalized patterns and an overall lower content than previously reported. It seems, however, that the Bushveld magmas were enriched in PGE's relative to average mafic rocks. A clear difference between the three magma types could not be substantiated. At present the PGE content of proposed parental melts of the Bushveld complex must be considered to be insufficiently known to warrant any quantitative models.     

Neuere Veröffentlichungen

Ohne Zusammenfassung     

Neuere Veröffentlichungen

Ohne Zusammenfassung     

Geophysical results in Austria with special regard to telluric measurements

Summary The paper treats the results of telluric measurements in the Austrian Molasse-Zone and in the Vienna Basin, supplemented with data of other geophysical methods and deep-wells. The analysis of the results shows that the telluric method supplies not only a picture with good reconnaissance proceeding from which further, especially seismic research can be planned more expediently, but can render good services in solving detailed problems too. The hypothesis concerning the anisotropy of sediments resp. its effect is verified by the results of modelexperiments too.

---

Zusammenfassung Die Arbeit behandelt die Ergebnisse der Tellurischen Forschungen in der österreichischen Molasse-Zone und im Wiener Becken unter Einbeziehung von Angaben anderer geophysikalischen Messungen und Tiefbohrungen. Die Analyse der Ergebnisse zeigt, dass die tellurische Methode nicht bloss eine gute geophysikalische Übersichtskarte ergibt, von der ausgehend weitere — in der Hauptsache seismische — Forschungen zweckentsprechender geplant werden können, sondern sie leistet auch recht gute Dienste bei der Lösung von Detaiproblemen. Die Hypothese über die Anisotropie der Sedimente bzw. ihr Effekt wurde auch durch die Ergebnisse von Modellversuchen bestätigt.

     

Study ofP-wave velocity below moho

Summary Seismograms recorded during the Trans-Scandinavian Profile of 1969 at the stations Kajaani, Oulu, Maaselkä and Sodankylä are used to determine theP wave velocities for distances from 400 km to 1300 km. An apparent velocity of 8.50 km/s was found. After making a correction due to the curvature of the earth the velocity of about 8.40 km/s was obtained at an approximate depth of 80 km. Some comparisons are made with other results from Fennoscandian area.     

Seismotectonics of Hindukush

Summary Elastic strain rebound increments for the Hindukush region has been studiedwhich revealed a cyclic pattern of strain release in this area where the rate of strain release decreases with time. The spatial distribution of earthquakes clearly defines the Pamir knot where most of the shocks are concentrated. The dip of the deep seated fault which produces the earthquakes so frequently comes out to be 54° dipping in the northwest direction. This fault is best developed between 70 to 300 kilometers and perhaps both these levels represent tectonic discontinuities.