Ichnostratigraphic correlation of Lower Palaeozoic clastics in the Kufra Basin (SE Libya)

Abstract

The Lower Palaeozoic deposits in North Africa are dominated by sandstones and shales which often lack biostratigraphically useful body fossils. Trilobite burrows (Cruziana) partly fill this gap and provide the basis for medium‐resolution stratigraphic interpretations. Several Ordovician‐Silurian ichnostratigraphically significant Cruziana forms have been found and studied in the Kufra Basin (SE Libya), including C. goldfussi and C. furcifera from the Lower Ordovician Hawaz Fm. and a new ichnospecies, C. kufraensis, occurring in transgressive sandstones at the base of the Lower Silurian Tanezzuft Fm. The upper Tanezzuft Fm. and Akakus Fm. typically contain C. acacensis, a form that is characteristic of the Lower Silurian of Northern Gondwana.

Evidence for Late Ordovician glaciation of Al Kufrah Basin, Libya

“…Therefore, as type sections or even type areas have yet to be formally established, Cambrian through Ordovician strata remain undifferentiated. Other outcrops of Lower Palaeozoic rocks do occur at the other basin margin uplifts, namely at the western basin flanks in Jabal Eghei (Seilacher et al, 2002) and in the Ennedi-Bourkou Range, Chad (Fig. 1).…”

“…Lüning et al, 1999) recognised ichnofauna of an Ordovician affinity in the pre-glacial strata, and hence we prefer the term Haouaz Formation for these deposits. It should be noted that much relies on the chronostratigraphic application of trace fossil analyses and subsequent studies elsewhere in southern Libya have contended that Cruziana trace fossils are age significant (Seilacher et al, 2002).…”

An unusual occurrence of Pedinopariops (Trilobita: Phacopidae) within siliciclastic facies in the Devonian of Awaynat Wanin, Libya

“…Although there are numerous specimens of Ordovician trilobites (e.g., Cocks & Fortey 1988, BecqGiraudon & Massa 1996 and a rich Ordovician to Devonian assemblage of arthropod trace fossils (e.g., Seilacher 1969, Seilacher et al 2002 known from Libya, the specimen described here appears to be the first Devonian trilobite described from the region. Future studies on Libyan trilobites may give further support for the use of phacopid trilobites as biostratigraphic indicators for the correlation of Devonian strata within and between basins in North Africa (e.g., McKellar & Chatterton 2008).…”

Neoproterozoic to Lower Palaeozoic successions of the Tandilia System in Argentina: implication for the palaeotectonic framework of southwest Gondwana

“…Hence, we consider the unconformity between Villa Mónica and Cerro Largo Formations as representing a large period of erosion (at least 1,000 m of sediments and 200 Ma; Gómez Peral 2008) to effectuate the lower diagenesis grade of the Cerro Largo Formation. Therefore, it shows that the Sierras Bayas Group and the Cerro Negro Formation reflect the geological evolution bracketed between c. 850 and 490 Ma, while the upper limit is determined by the occurrence of Neoproterozoic stromatolite types in the Sierras Bayas Group (Gómez Peral et al 2007), and the lower limit drawn by the occurrence of Ordovician trace fossils in the overlying Balcarce Formation (Seilacher et al 2003).…”