Amsterdam, HollandReconnaissance sedimentology and hydrocarbon biomarkers of Ediacarian microbial mats and acritarchs, lower Ungoolya Group, Officer BasinAmsterdam, Holland

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Early and Middle Silurian conodonts from midwestern New South Wales

SIGLETIB: RN 5205 (89) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Late Silurian and Early Devonian biostratigraphy in the Hill End Trough and the Limekilms area, New South Wales

The first recorded graptolites from the Cheslcigh Formation of the Limekilns district are Monograptus prognatus, ?M. transgrediens, Pristiograptus sp. cf. P. shearsbyi and Linograptus posthumus, which unequivocally indicate a Prldolt (Late Silurian) age for the formation. The Silurian-Devonian boundary appears best placed at approximately the boundary between the Chesleigh Formation and the overlying Cookman Formation, despite the presence of the early Lochkovian graptolite Monograptus uniformis uniformis much higher stratigraphically in the Limekilns Formation. In the Hill End Trough succession, the Turondale Formation has yielded conodonts including Amydrotaxis praejohnsoni, which indicates the delta to pesavis conodont Zones of late Lochkovian (Early Devonian) age. Conodonts from the upper p ayt of the Cunningham Formation, at a locality in the Trough west of Mudgee, include Polygnathus nothoperbonus /P. inversus, indicating theperbonus zone of middle Emsian age. The base of the Cunningham Formation is diachronous, being late Lochkovian (delta Zone) - the same age as the Turondale Formation - on the west flank of the Trough as previously reported, and late Pragian in the east. The youngest faunas found in the unit are late Emsian

ʻConodont pearlsʼ do not belong to conodonts

We investigated the mineralogical and chemical signatures of enigmatic microspherules commonly recovered in conodont residues and referred to in literature as ‘conodont pearls.’ Comparison between these ‘pearls,’ associated conodonts and other phosphatic skeletal elements present in the same stratigraphical level was run in an effort to reveal any possible relation between ‘conodont pearls’ and the joined groups so to finally provide a response on the affinity of these spherules