ALBERT

Description / Table of Contents: Abstract 172 carbonate samples from the Alps (mainly the Northern Calcareous Alps) ranging from Norian to Middle Liassic age, have been investigated for their18O/16O-content. Paleotemperatures have been determined. The analysed samples — fossils, mainly with primary calcitic shells, ooids and carbonatic sediments —were carefully selected by optical and x-ray methods. The results are given in fig. 2. Paleotemperatures are plotted in groups of the same age and equal or similar facies. The maximum of each group is assumed to represent the average water-temperature of that time. The interpretation of the paleotemperatures refers also to paleogeographic factors, e. g. bathymetry and salinity. The Noric shelf-sea paleotemperatures are in the range of about 25° C and show a systematic decrease to the Upper Rhaetian; a minimum temperature during the Lower Liassic (18° C) was followed by a warmer climatic period in the Middle Liassic. It is assumed that the Upper Triassic coral-reefs of the Northern Calcareous Alps died out because of the low temperature.

Description / Table of Contents: Abstract The largest Ionian island Cephalonia is situated on the edge of the Greek shelf. To the west the slope (20% average) extends to the Ionian fault scarp. This area is characterized by young tectonic activity (last disastrous earthquake in 1953) with dominant N-S and NE-SW fault directions. This paper constitutes the first account of the marine and Quaternary geology of Cephalonia. Late Pleistocene (? Tyrrhen III) red algae-rich limestones - up to 6,5 m thick - with interbedded sand layers transgress steeply folded Plio-Pleistocene and Eocene sediments. In addition, relative sea level changes in Quaternary time are indicated by a submarine platform at −26 m NN. and 5 elevated shorelines, partly with wave-cut notches and borings, at heights of about 15 m, 45 m, 90 m, 150 m and 190 m, whose correlation with other so-called high-sea-levels of the Mediterranean area is doubtful. Shore- and nearshore sediments mainly consist of eroded coast material and reworked Pliocene which locally crops out on the sea floor, The outer shelf sedimentation is characterized by the deposition of marly foraminiferal ooze which undergoes bioturbation. Because of strong currents the ridge between Cephalonia and Zante is free of recent sediment. A swash mark entirely composed of the tests of sessil foraminiferas (Miniacina miniacea) is described.

Description / Table of Contents: Abstract The „Geiselstein-Oolith“ is the thickest oölitic formation of the Alps. Its thickness can rise up to 180 m at the type locality, Geisel-Stein, E of Füssen, Upper Bavaria, Northern Calcareous Alps (fig. 3). This sequence has been dated before as Upper Raetian. New paleontological evidence has proved Lower Jurassic Age (Sinemurian). But even with Liassic dating this oölite can still be understood as the terminating facies of the Raetian and Raetoliassic oölites of the reef complex of equal age. The first detailed study covers the western part of the Northern Alps as far as Salzburg (fig. 1). Further to the E., in the Wienerwald area, a similar distribution of oölites is known. We know oölites of the same age and of very close similarity from the Southern Alps, the Appenine, and the Carpathian. The results are: The Liassic oölites are restricted to a narrow belt perhaps less than 1 km wide, and of the remarkable length of approximately 120 km (fig. 1). In parts the oölitic facies wedges out to a few meters by intertonguing with crinoidal and sponge sediments (fig. 3). On the whole these oölitic bodies have a more or less lenticular shape. The Raetian and Raetoliassic oölites show no distinct pattern of distribution; they are related to the reef complex, especially to the arenitic parts of the back reef area. There are some differences between Raetian and Liassic oölites: The Liassic oölite has few skeletal fragments (mean 3%: mainly crinoids and some brachiopods), while the Raetian oölite has a mean of 13% of its volume and is rich in species and in individuals. Obviously this is the result of the reef facies. The granulometric analysis of the oöid compound in the Liassic samples reveals a higher oöid percentage, larger median and maximum grain size and better sorting. These differences are more important for the interpretation of facies than for the stratigraphy. An attempt has been made to compare the fossil oölites with Recent oölitic sands of the Great Bahama Bank. The similarities between the Liassic oölite and the Recent oölitic sands of the barrier rim are very close, as far as granulometric data and the patterns of distribution are concerned. The Raetian oölites can be better compared to the oölite containing sediments of the „coralgal facies“, although this Recent sediment is a facies bordering the bank, while the Raetian is related to the reef complex. The many analogies between Recent and fossil oölites justify the given interpretation of sediment formation and reconstruction of the paleogeography of the Tethyan geosyncline. A method is suggested for the determination of the true grain size of oöids in thin sections.