| Popis: |
EMSIANMiospore assemblages which can be positively assigned to the Early Devonian have, to date, only been recorded from core material from Well A1-33. Assemblages of Emsian age were recorded from the interval 8079 to 8091 ft. whilst assemblages from 8055 to 8076 ft. contain some taxa which are common in the Emsian elsewhere but are not diagnostic. Assemblages recovered from sediments in the interval 9700 to 9709 ft. in Well A1-33 were dominated by leiospheres together with smaller numbers of acanthomorph acritarchs. The age of this interval is unknown but it could be as old as Ordovician.The Emsian assemblages recovered from the interval between 8079 to 8091 ft. contain a wide variety of azonate miospores together with species possessing an equatorial crassitude, specimens with zonate extensions are rare. Miospores with sculptural or structural modifications around their equators are relatively common i.e. ?Procoronaspora sp., Diatomozonotriletes sp. A. and Craspedispora craspeda. The presence in these assemblages of Emphanisporites annulatus, E. erraticus, E. rotatus, E. cf. decoratus, E. obscuras, Dibolisporites eifeliensis, D. cf. gibberosus, D. echinaceas, Apiculiretusispora brandtii together with small tripapillate miospores suggest an Early or Middle Emsian age to be probable. The assemblages are closely comparable with Emsian microfloras recorded in the Polignac Basin of Algeria (Jardiné & Yapaudjian, 1968) and the Rhadames Basin of Western Libya (Massa & Moreau-Benoit, 1976).EIFELIANMiospore assemblages of probable Eifelian age have been recovered from Well A1-37 from cored material at 10674 ft. The miospore populations which are extremely well preserved contain . . . |
