Results 51 to 60 of about 1,663 (126)

DEVONIAN-CARBONIFEROUS MAGMATISM AND METALLOGENY IN THE SOUTH URAL ACCRETIONARY-COLLISIONAL SYSTEM

Геодинамика и тектонофизика, 2021
The oceanic stage in the history of the South Urals completed in the Ordovician – Early Silurian. The Ordovician through Devonian events in the region included the formation of an island arc in the East Ural zone from the Middle Ordovician to Silurian ...
A. M. Kosarev, A. G. Vladimirov, A. I. Khanchuk, D. N. Salikhov, V. B. Kholodnov, T. A. Osipova, G. A. Kallistov, I. B. Seravkin, I. R. Rakhimov, G. T. Shafigullina   +9 more
doaj   +1 more source

The Early Devonian (Emsian) acrotretid microbrachiopod Opsiconidion minor Popov, 1981, from the Alaska/Yukon Territory border and Novaya Zemlya [PDF]

Estonian Journal of Earth Sciences, 2020
New records of the poorly known acrotretid (Biernatidae) microbrachiopod Opsiconidion minor Popov are described from middle Emsian strata of the Ogilvie Formation in east-central Alaska and the adjacent Yukon Territory, Canada, and compared with new ...
Lars E. Holmer, Robert B. Blodgett, Yue Liang, Zhifei Zhang   +3 more
doaj   +1 more source

New Zealand Geological Timescale 2025

New Zealand Journal of Geology and Geophysics, Volume 69, Issue 1, March 2026.
New Zealand Geological Timescale 2025 (NZGT 2025) is the first comprehensive update and revision of the New Zealand Geological Timescale in a decade. The criteria used to establish age ranges of New Zealand Stages within the NZGT have been reviewed, calibrated, and revised where required against the 2023/04 International Chronostratigraphic Chart and ...
Christopher D. Clowes, James S. Crampton, Kyle J. Bland, J. Ian Raine, Andrew F. Boyes, Hamish J. Campbell, Erica M. Crouch, Martin P. Crundwell, Neville Hudson, Elizabeth M. Kennedy, Donald A. B. MacFarlan, Hugh E. G. Morgans, Marcus D. Richards, Matthew W. Sagar   +13 more
wiley   +1 more source

Definition of the Eifelian- Givetian Stage boundary

, 1995
he boundary for the Eifelian-Givetian Stage Global Stratotype Section and Point (GSSP) in the Middle Devonian has been ratified by the ICS and the IUGS and is placed in a section at Jebel Mech Irdane in the Tafilalt of Morocco.
House, M. R., Weddige, K., Walliser, Otto Heinrich, Bultynck, P., Becker, R. T.   +4 more
core   +1 more source

Givetian megaspore assemblages of the Mikhailovksy mine (Kursk oblast)

Известия высших учебных заведений: Геология и разведка
Background. Disperse megaspores from the Givetian deposits of the Mikhailovsky mine, Kursk Oblast, were studied for the first time. Following chemical maceration of the samples, their selection and identification, 12 species belonging to 8 genera of ...
D. I. Marinina, O. A. Orlova
doaj   +1 more source

Sediment‐stressed reefs over the past 420 Myr

The Depositional Record, Volume 12, Issue 1, February 2026.
In order to fully elucidate the relationship between siliciclastic sedimentation and reef development, there needs to be a significant step change in how we record ancient and recent reefs. Only through the collection of constrained quantitative data, we can progress beyond the largely conjectural associations postulated for many ancient reefal systems.
Tanja Unger, Stephen W. Lokier, Markus Aretz, Matthieu Saillol, Adrian Immenhauser   +4 more
wiley   +1 more source

The Spatial and Temporal Evolution of Mixed Carbonate‐Clastic Mud‐Dominated Basin Fill Successions: The Middle to Late Devonian Shelf Margin, Western Canada

Basin Research, Volume 37, Issue 6, November/December 2025.
The spatial interplay between updip clastic and carbonate depositional systems and downdip detrital and biogenic mud dominated depositional systems are mapped temporally using the sequence stratigraphic method to predict the occurrence of aquifers, petroleum reservoirs and organic‐rich deposits. ABSTRACT Middle to Upper Devonian strata preserved in the
Rene Jonk, Kevin Bohacs, Ken Potma
wiley   +1 more source

A new species of the antiarch Microbrachius from the Middle Devonian (Givetian) of Belarus [PDF]

Estonian Journal of Earth Sciences, 2017
A new antiarch species Microbrachius kedoae n. sp. is described from the Middle Devonian (Givetian) of Belarus. The species is based on isolated dermal plates recovered from a borehole near the village of Gavrilchitsy about 25 km southwest of the city of
Elga Mark-Kurik, Michael J. Newman, Ursula Toom, Jan L. den Blaauwen   +3 more
doaj   +1 more source

CONODONT BIOSTRATIGRAPHY AND LITHOSTRATIGRAPHY OF THE LATE GIVETIAN–EARLY FRASNIAN INTERVAL IN THE ARPI SECTION (CENTRAL ARMENIA)

Rivista Italiana di Paleontologia e Stratigrafia
The Givetian–Frasnian (G–F) transition marks a time of significant palaeoenvironmental perturbations and biotic turnover, yet its stratigraphic record in the southern Caucasus remains poorly constrained.
Vahram Serobyan, VACHIK HAIRAPETIAN, MELINE TSATRYAN, TANIEL DANELIAN, FRÉDÉRIC BOULVAIN, NUNE AVAGYAN, ARAYIK GRIGORYAN   +6 more
doaj   +1 more source

New data on Karksiodus (Chondrichthyes) from the Main Devonian Field (East European Platform) [PDF]

Estonian Journal of Earth Sciences, 2014
New teeth belonging to Karksiodus mirus Ivanov & Märss (Chondrichthyes) were found together with putative chondrichthyan scales in five new localities of the Leningrad Region, northwestern Russia, within the Aruküla and Burtnieki regional stages ...
Alexander Ivanov, Tiiu Märss
doaj   +1 more source