Articles | Volume 4, issue 1
01 Mar 1985
 | 01 Mar 1985

Middle Triassic (Anisian-Ladinian) Palynomorphs

W. A. Brugman, J. W. Eggink, and H. Visscher

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 . . .