Results 41 to 50 of about 230 (171)

Ordovician ironstone of the Iberian margin: Coastal upwelling, ocean anoxia and Palaeozoic biodiversity

The Depositional Record, Volume 6, Issue 3, Page 581-604, September 2020., 2020
Middle to Upper Ordovician ironstone and associated sedimentary rocks of the West Asturian‐Leonese and Cantabrian tectonostratigraphic zones, Spain, provide new information regarding the Palaeozoic Fe cycle and the palaeoceanography of the Rheic Ocean.
Peir K. Pufahl, Alexandra D. Squires, J. Brendan Murphy, Cecilio Quesada, Stephen W. Lokier, J. Javier Álvaro, Jason Hatch   +6 more
wiley   +1 more source

A new marrellomorph euarthropod from the Early Ordovician of Argentina [PDF]

Acta Palaeontologica Polonica, 2017
Marrellomorphs (class Marrellomorpha) are a group of Paleozoic arthropods with a very poor fossil record. Here we describe a new marrellomorph arthropod Mimetaster florestaensis sp. nov. from the Tremadocian (earliest Ordovician) of Argentina.
María J. Aris, Jose A. Corronca, Sebastián Quinteros, Paolo L. Pardo   +3 more
doaj   +1 more source

Evaluation of a New Zealand Tremadocian trilobite

Geological Magazine, 1979
SummaryDionide hectoriReed, 1926, is shown on the basis of new collections from the type area in New Zealand to be a Tremadocian ceratopygide close toHysterolenus. The species was placed inTaihungshaniaby Kobayashi (1941). It was provisionally retained in the Taihungshaniidae by Lu (1975) who madehectoritype species of a new genusHectoria ...
openaire   +2 more sources

New Insights into the Early Diversification of the Ostracoda: Tremadocian Ostracods from the Cordillera Oriental, Argentina [PDF]

Acta Palaeontologica Polonica, 2012
New species of ostracods from the Tremadocian in the northwest region of Argentina are described. These are among the earliest well-documented records of ostracods, which shed new light onto the early diversification of the group. The described fauna consists of seven species, five of which are new: Saltite uchuy sp. nov., Saltite kuraq sp.
Salas, Maria Jose, Vaccari, Norberto Emilio   +1 more
openaire   +2 more sources

Depositional environments and stratigraphy of the Upper Cambrian-lower Ordovician Santa Rosita formation at the Alfarcito area, Cordillera Oriental, Argentina: integration of biostratigraphic data within a sequence stratigraphic framework

Latin American Journal of Sedimentology and Basin Analysis, 2021
The Upper Cambrian-Tremadocian rocks exposed in the Alfarcito area of Cordillera Oriental, northwest Argentina reveal a series of transgressive-regressive cycles punctuated by incision of fluvio-estuarine valleys.
Luis A. Buatois, Fernando J. Zeballo, Guillermo L. Albanesi, Gladys Ortega, N. Emilio Vaccari, M. Gabriela Mángano   +5 more
doaj   +2 more sources

First description of Skolithos burrows from the Cambrian–Ordovician boundary interval of the Central Anti-Atlas, Morocco [PDF]

Estonian Journal of Earth Sciences, 2017
Skolithos burrows indicate high-energy nearshore environment. In this paper, abundant Scolithos burrows from two particular levels of the Cambrian–Ordovician boundary interval of the Central Anti-Atlas, Morocco, are described for the first time.
Abdelfattah Azizi, Olev Vinn, Khadija El Hariri, Ahmid Hafid, Khaoula Kouraiss   +4 more
doaj   +1 more source

Cambrian Furongian–Middle Ordovician conodonts in the northeastern margin of the South China Block (Chuzhou, Anhui province) and their paleogeographic implications [PDF]

Journal of Micropalaeontology
The South China Block is crucial for the global study of Cambrian to Ordovician conodont biostratigraphy, but research on its northeastern margin is relatively scarce.
B. Hu, S. Li, C. Cheng, M. Li, W. Xie, X. Wei   +5 more
doaj   +1 more source

Revisiting the Hummeln structure, Sweden—A shallow marine Cambrian impact structure

Meteoritics &Planetary Science, Volume 61, Issue 7, Page 1213-1242, July 2026.
Abstract Hummeln is a simple impact structure located in south‐eastern Sweden. It is approximately 1.2 km in diameter and almost completely covered by a lake. Here, we present the first detailed investigation of impactites and mapping of the 164.25 m deep drill core Hummeln‐1 with a focus on impact metamorphism and the impact process.
S. Alwmark, J. Granbom, P. Ahlberg, M. Calner, S. Richoz, K. J. Gajewska, W. R. Hyde, K. Ljung, C. Alwmark   +8 more
wiley   +1 more source

Palaeoscolecids from the early Cambrian Guanshan biota, Yunnan Province, China

Papers in Palaeontology, Volume 12, Issue 1, January/February 2026.
Abstract Palaeoscolecidomorphs (Palaeoscolecida and Cricocosmiidae) are widespread early Palaeozoic worms crucial to understanding the early evolution of Ecdysozoa. They are well known from the early–middle Cambrian of the Yangtze Platform of South China, but research has disproportionately focused on the well‐known Cambrian Stage 3 Chengjiang biota of
Xiaomei Shi, Richard J. Howard, Guangxu Zhang, Xiaoya Ma   +3 more
wiley   +1 more source

Biostratigraphy and correlation of the Cambrian Series 2 (Stage 4) to Miaolingian (Wuliuan) Thorntonia Limestone, south‐eastern Georgina Basin (Queensland, Australia)

Papers in Palaeontology, Volume 11, Issue 5, September/October 2025.
Abstract The Australian Cambrian stratigraphic record is one of the most complete for any continent. However, there is a general division, with older Cambrian rocks in South Australia (predominantly Terreneuvian, Stage 2 to Miaolingian, Wuliuan) and younger rocks in northern Australia (mostly latest Series 2, Stage 4 and younger), with minimal ...
Marissa J. Betts, Patrick M. Smith, John R. Paterson, Evelyn M. Mervine, Daniel A. Stirling, James D. Holmes   +5 more
wiley   +1 more source