Die Bedeutung geochemisch-stratigraphischer Bezugshorizonte für die Altersstellung der Antimonitlagerstätte von Schlaining im Burgenland, Österreich

Zusammenfassung Es wird die Frage gestellt, ob es bei der Entwicklung unseres Planeten typische, an weltweite Lineamente gebundene Metallzufuhren in die Erdkruste gab, die ihren Erzinhalt so schicht- und zeitgebunden absetzten, daß er als Zeitmarke gewertet und zu stratigraphischen Einstufungen und Parallelisierungen auch fossilleerer Gesteine verwendet werden kann. Die Existenz derartiger geochemischer Leitschichten mit typischen Leitparagenesen und diejenige geochemisch-stratigraphischer Bezugshorizonte wird bejaht. Sie wird an Hand von Antimonitlagerstätten mit Scheelitführung bzw. an reinen schichtgebundenen Scheelitvorkommen (mit zum Teil Molybdän-, Beryllium- oder Goldführung) diskutiert. Hierbei wird näher auf die Altersstellung und Genese der Antimonitvorkommen von Schlaining im österreichischen Burgenland (in der Rechnitzer Schieferserie) eingegangen. Diese liegen räumlich isoliert zwischen den schichtgebundenen, altpaläozoischen Antimonit/Zinnober-Scheelit-Lagerstätten der Ostalpen und denen der Westkarpaten, die gemeinsam als ein geochemisch-stratigraphischer Bezugshorizont gewertet werden. Daraus wird für die Schlaininger Antimonitvorkommen das bereits in neueren, ungarischen Arbeiten für die Rechnitzer Schieferserie angegebene, altpaläozoische Alter bestätigt.

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Attention has been given to the question, whether during the evolution of our planet typical metals were conveyed along worldwide lineaments to the earth's crust, whereby ores have been deposited so stratabound and timebound that the ore content itself may be considered as a time indicator and may be used in stratigraphical positioning and correlating of rocks, even if these are not fossiliferous. The existence of such geochemical index horizons, containing typical index parageneses and of geochemical-stratigraphical marker horizons has been affirmed. The question has been discussed in connection with stibnite deposits containing scheelite and with stratabound scheelite occurrences free of stibnite (partially containing molybdenum, beryllium or gold). The age and genesis of the stibnite occurrences near Schlaining in the Burgenland, Austria (within the Rechnitz Schist Series) has been considered closely. These isolated occurrences are located between the stratabound, Early Paleozoic stibnite/cinnabar-scheelite deposits of the Eastern Alps and those of the Western Carpathians, which together are regarded as one common geochemical stratigraphical marker horizon. Thereby, not only the Early Paleozoic age of the Rechnitz Schist Series is confirmed, as recent Hungarian publications propose, but also the Early Paleozoic age of the Schlaining stibnite occurrences.

     

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Gebirgsmechanische Versuche beim Bau eines Wasserzufuhrstollens im Gebirge mit hohen Initialspannungen

Rock Mechanics and Rock Engineering - Beim Ausbruch des Kalottenstollens für den westlichen Wasserzufuhrstollen des Kraftwerkes Vietas traten Schwierigkeiten in Form von heftigen...     

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Factor analysis of stream sediment geochemical data from the Mount Nansen area,Yukon Territory,Canada

Q- and R-mode factor analytical studies were made of 158 stream sediment samples from the Mount Nansen area, Yukon Territory, analyzed for Cu, Pb, Zn, Mo, Ni, Ag, and Sb. R-mode results were more clear-cut than were Q-mode in terms of ease of interpreting geological significance of individual factors, although results of both methods were very comparable. The 3-factor R-mode model accounted for 79.9 percent of the variation in the data. Factor 1, a Pb-Zn-(Ag) factor correlated with Mount Nansen volcanic rocks and particularly with known Pb-Zn-Ag-Au veins within those rocks. Factor 2, a Cu-Mo factor correlated with porphyric intrusions known to contain Cu-Mo mineralized zones. Factor 3, an Sb-(Ag) factor is, as yet, not adequately explained in terms of geology. The main additional contribution of the Q-mode study is the communalities. Samples that depart from the norm (i.e. do not agree well with the 3-factor model) are readily apparent because of low communalities and must be considered anomalous in the general sense until an adequate explanation for this difference is found.     

The recovery of sodium chloride from sea water

The recovery of sodium chloride from the sea has been practised since ancient times. Modern knowledge of phase rules enables us to recover fairly clean sodium chloride from sea water, which consists of a complex mixture of salts and other minerals. According to quality requirements, two procedures can be applied; solar pre-concentration of the sea water with subsequent vacuum distillation, or solar pre-concentration with subsequent over-saturation and precipitation of the salt. The individual product requirements and cost factors have to be diligently studied in order to decide which procedure is the more feasible.     

Pollution effects of the Tuy River on the central Venezuelan coast: Anthropogenic organic compounds and heavy metals in Tivela mactroidea

Bivalve samples were collected at seven sampling stations located between the town of Machurucuto and the Bay of Higuerote, Venezuela, covering approximately 70 km of coastline. Samples were collected both east and west of the Tuy River mouth, which has a plume known to move in a north-westerly direction. Petroleum hydrocarbons, both aliphatic (n-alkanes and UCM) and polyaromatic (PAHs), were detected and quantified in the samples. These hydrocarbons were found to be primarily derived from fossil fuels. Halogenated organics consisted mostly of polychlorinated biphenyls (PCBs) and some chlorinated pesticides, primarily of the DDT group. Heavy metals such as Pb, Cu, Ni, Zn, Cr and Cd were analysed in the samples. The results clearly show the influence of the Tuy River plume on the water quality of the coastal zone, particularly that located west of the river mouth. One sampling station, located just east of the river mouth, also showed significant influence from the river plume.