Meteoritics &Planetary Science, EarlyView.Abstract The Tvären structure in southeastern Sweden has been listed as a confirmed marine‐target impact structure for decades. However, to date, no measurements and/or indexed data of planar deformation features in quartz grains from the structure have been published or any other unequivocal evidence of impact.
Katarzyna J. Gajewska +6 more
wiley +1 more source
Ancestral patterning of tergite formation in a centipede suggests derived mode of trunk segmentation in trilobites. [PDF]
PLoS ONE, 2012 Trilobites have a rich and abundant fossil record, but little is known about the intrinsic mechanisms that orchestrate their body organization. To date, there is disagreement regarding the correspondence, or lack thereof, of the segmental units that ...
Javier Ortega-Hernández, Carlo Brena
doaj +1 more source
An electron backscatter diffraction study of geesops: a broader view of trilobite vision? [PDF]
, 2008 The calcite eyes of trilobites have been studied for over 100 years using methods including light microscopy (e.g. Clarke 1889; Campbell 1975; Towe 1973; Clarkson 1979 and Bruton and Haas 2003) and more recently cathodoluminescence (CL) imaging coupled ...
Lee, M.R., Owen, A.W., Torney, C.
core
The first hirnantian (Uppermost Ordovician) Odontopleurid trilobite from western Gondwana (Argentina) [PDF]
, 2014 An odontopleurid trilobite remain is described for the fi rst time from Hirnantian (uppermost Ordovician) rocks of Western Gondwana. Very rare material, represented by a single left librigena, comes from a new fossil locality of the Don Braulio Formation
Halpern, Karen +2 more
core +1 more source
Metacryphaeus rotundatus, um Novo Elemento da Fauna de Trilobites Calmoniidae (Phacopida), da Formação Ponta Grossa (Devoniano), Bacia do Paraná, Brasil [PDF]
Geologia USP. Série Científica, 2008 Trilobites Calmoniidae (Delo, 1935) constituem o grupo de Phacopida mais abundante e diversificado do registro fóssilda Formação Ponta Grossa, Devoniano, Sub-bacia Apucarana.
Sabrina Pereira Soares +2 more
doaj +3 more sources
Geologic quadrangle map no. 47 [PDF]
, 1978 Process Steps: 1. Either: a) a Portable Document Format (PDF) version of the map provided the Bureau of Economic Geology, University of Texas at Austin was converted from pdf to Tagged Image File Format (TIFF) or b) a paper map was scanned and saved in ...
Barnes, Virgil E. (Virgil Everett), 1903-1998
core +1 more source
New data on the Lower Cambrian trilobites of Cortijos de Malagon (Spain)
Estudios Geologicos, 1989 En este trabajo se describe la fauna de trilobites del Cámbrico inferior de las areniscas de los Cortijos de Malagón en el SE español. Comprende Realaspis (?) sp., Kingaspis (?) sp.; cf. Latoucheia sp. y Lusatiops afI. ribotanus. Richter y Richter, 1948.
Mª D. Gil Cid, J. B. Jago
doaj +1 more source
Putative Analogs of Pyrite Suns Forming in Proglacial Alaska Mudflats
Journal of Geophysical Research: Biogeosciences, Volume 131, Issue 5, May 2026.Abstract Disc‐shaped pyrite suns of the Pennsylvanian age Anna Shale are thought to have formed where pressure restricted pyrite crystal growth to a flattened disc shape during diagenesis at the Anna Shale and the underlying Herrin coal boundary.
Heather L. Fair +2 more
wiley +1 more source
, 2011 The Cambrian rocks of Wales mostly lie within the Avalon composite terrane, apart from a small area of Cambrian rocks of the Monian composite terrane that is discussed in Chapter 9.
Molyneux, S.G., Rushton, A.W.A.
core
An in situ shelly fauna from the lower Paleozoic Zapla diamictite of northwestern Argentina: implications for the age of glacial events across Gondwana [PDF]
, 2015 A shelly fauna from the upper part of the Zapla glacial diamictite includes thelingulate brachiopod Orbiculoidea radiata Troedsson, the rhynchonelliforms Dalmanella cf. testudinaria (Dalman) and Paromalomena sp., the bivalve Modiolopsis?
Benedetto, Juan Luis Arnaldo +3 more
core +2 more sources