New detrital-zircon geochronologic data reveal that a through-going paleoriver connected Texas with Nevada in Late Triassic time. Sandstone from the Upper Triassic Santa Rosa Sandstone (Dockum Group) from northwestern Texas contains a detrital zircon suite nearly identical to that found in western Nevada in the Upper Triassic Osobb Formation (Auld Lang Syne Group, correlative with the Chinle Fo...

Kullingia is considered a key taxon in demonstrating the presence of terminal Proterozoic–early Cambrian chondrophorine hydrozoans. However, Kullingia concentrica from the Lower Cambrian of northern Sweden possesses several features that show that it is not a body fossil but that it was formed by current or wave-induced rotation of an anchored tubular organism, possibly a sabelliditid. A scratc...

Steams, C. and Van der Voo, R., 1987. Paleomagnetic results from the Lower Devonian Llandstadwell Formation, Dyfed, Wales. Tectonophysics, 143: 329-334. A paleomagnetic investigation of the Lower Devonian Llandstadwell Eormation in southwest Wales has yielded a characteristic direction (declination = 196’. inclination = 5’) that passes a fold test. Comparison of the corresponding virtual geomag...

A new approach to maximize data recovery from siderite-hosted fossils is presented. Late Carboniferous trigonotarbids (Arachnida: Trigonotarbida) from Coseley, UK, were chosen to assess the potential of high-resolution X-ray micro-tomography (XMT). Three-dimensional computer reconstruction visualizes the animals at 20 microm or better resolution, resolving subtle and previously unseen details. ...

During the mid-Palaeozoic, vascular land plants (i.e., tracheophytes) underwent a great radiation that triggered development of biosphere – so-called Silurian–Devonian terrestrial revolution. However, little is known about how different plant groups impacted this process. A newly constructed dataset macrofossil genera used to characterize tempo and mode vegetation it spread out over subaerial h...

Exceptional braincase preservation in some Devonian placoderm fishes permits interpretation of muscles and cranial nerves controlling eye movement. Placoderms are the only jawed vertebrates with anterior/posterior obliques as in the jawless lamprey, but with the same function as the superior/inferior obliques of other gnathostomes. Evidence of up to seven extraocular muscles suggests that this ...

One of the most intensively examined and abundantly documented structures in the animal world is insect mouthparts. Major structural types of extant insect mouthparts are extensive, consisting of diverse variations in element structure within each of the five mouthpart regions•labrum, hypopharynx, mandibles, maxillae, and labium. Numerous instances of multielement fusion both within and among m...

Abstract The Black Warrior foreland basin records sedimentation associated with the development of intersecting Ouachita and Alleghanian thrust belts along southern margin Laurentia. Mississippian–Pennsylvanian units in are interpreted to be sourced from either northern Appalachians mid-continent or more regionally nearby belt. We present detrital zircon U-Pb ages Th/U values Paleozoic that ind...

Four metasedimentary zircon populations from different tectonometamorphic units of the Central and the Northern Schwarzwald (Variscan belt, SWGermany) were investigated using SEM, cathodoluminescence and SHRIMP dating. Despite partially strong modifications of primary internal morphologies during Variscan metamorphism at amphibolite (750 C, 0.4– 0.6 GPa) and granulite-facies conditions (950–1,0...