Abstract. Initial results of the palynostratigraphical research in the Triassic of northeast Libya indicate the presence of Middle Triassic in several deep-wells. There is some evidence that the uppermost part of the Early Triassic (Late Scythian) as well as the early part of the Late Triassic (Karnian) may also be present. Additional palynological samples will need to be studied to confirm this view.Most Triassic assemblages in northeast Libya show a striking dominance of the monolete lycopodiophytic miospore Aratrisporites; this genus is represented by a large number of species (A. centratus, A. parvispinosus, A. strigosus, A. saturni, A. paenulatus, A. tenuispinosus, A. ovatus). A similar development is known to occur in the Middle Triassic of Australia and Pakistan. Bisaccate pollen is commonly present in the assemblages. Representatives of Triadispora and Lunatisporites are also frequently recorded.On the basis of a few additional forms, two palynologically distinctive intervals may be recognized within the Middle Triassic:Anisian interval. On the basis of Stellapollenites thiergartii, Strotersporites n. sp. of Visscher and Brugman 1981 (not illustrated) and Angustisulcites grandis, an Anisian age for the lower interval is indicated. The latter two species suggest the Early Anisian. The assemblages can be compared with similar assemblages from the Alpine Anisian in Europe (Visscher & Brugman, 1981; Brugman, in prep) and the Salt Range, Pakistan (Brugman & Baud, in prep).Ladinian interval. The upper part of the Libyan Middle Triassic is characterised by the absence of characteristic Anisian elements, and the incoming of rare representatives of the Circumpolles-group . . .
Both paleomagnetism and palynology may furnish useful diagnostic facts for recognizing long-distance movements of the earth’s crust. With respect to the relative positions of North America and Eurasia, paleomagnetic and palynological data contribute evidence in support of the theory of continental drift. However, the conclusions based on paleomagnetic measurements sometimes disagree with palynological observations. Paleomagnetic data obtained in northeastern Italy, southern France and northern Spain differ considerably from those from Mesc-Europe. In recent geotectonical considerations this has been attributed to the so-called Tethys twist having effected a post-Carboniferous westward displacement of the structural units of Italy, southern France and Spain.
Palynology, however, reveals a highly uniform geological history of both Meso-Europe and a part of Alpine Europe during Permian and Triassic times. Biostratigraphical correlations between the two realms are possible by studying the palynological assemblages obtained from Permian and Triassic evaporites or associated sediments. Contemporaneous, short periods of evaporite deposition in both Meso-Europe and the Mediterranean region are suggested by the striking uniformities in Lower Mesophytic vegetations as reflected by sporae dispersae. There is every indication that there was a comparable evolution in the physiographical and climatological conditions which opposes the hypothesis of a mobile Tethys belt during Permian and Triassic times.
Excessive acid rainfall associated with emplacement of the Siberian Traps magmatic province is increasingly accepted as a major contributing factor to the end-Permian biosphere crisis. However, direct proxy evidence of terrestrial acidification is so far not available. In this paper, we seek to determine the probability that relative proportions of extractable monophenolic components from soil-derived organic matter in marine sediments provide a molecular proxy for estimating soil acidity. Intermittently low and high ratios of vanillic acid to vanillin detected in latest Permian and earliest Triassic deposits of the southern Alps, Italy, support concepts of pulses of severe acidification (pH <4) during the main phase of the biosphere crisis.
