New data on stratigraphy of the Silurian strata of Tagil structure in the Northetrn Urals by G. A. Petrov, G. N. Borozdina, N. I. Tristan, G. A. Il’Yasova

“…Volcanic rocks in researching area were formed during period from Late Ordovician to Early Devonian and were attributed to Palnikshor (Vyja), Shemur, Pavda, Imennya and Sos’va (Tura) formations. …”
Get full text

Zircon ages delimit the provenance of a sand extrudite from the Botucatu Formation in the Paraná volcanic province, Iraí, Brazil by VITER M. PINTO, LÉO A. HARTMANN, JOÃO O.S. SANTOS, NEAL J. MCNAUGHTON

“…The zircon U-Pb ages reflect four main orogenic cycles: Mesoproterozoic (1155-962 Ma), latest Proterozoic-early Cambrian (808-500 Ma) and two Palaeozoic (Ordovician- 480 to 450 Ma, and Permian to Lower Triassic- 296 to 250 Ma). …”
Get full text

The Distribution Law of Floor Fracture Zone of No.16 Coal Mining Face in Limin Coal Mine by LIU Dongming

“… To avoid the water inrush from the floor of the working face, according to the characteristics of large mining height and long working face of 1603 first mining face of 16 coal above Ordovician limestone in Limin Mine, theoretical calculation and numerical simulation method were used to study the distribution of the rupture zone of the 1603 working face. …”
Get full text

Geophysical exploration methods on bauxite reservoirs in L gasfield, Ordos Basin by Qi Yu, Li Dan, Yu Shanshan, Li Qixin

“…As the overlying strata of Majiagou Formation of Lower Ordovician in Lower Paleozoic, bauxite has always been considered a regional cap rock and has not been widely followed with interest. …”
Get full text

Regarding the age and composition of gneisses from the basement of West-Siberian Plate’s north-western part by K. S. Ivanov, Yu. V. Erokhin, D. V. Elizarov, S. P. Shokal'sky

“…U-Pb, Sm-Nd, Rb-Sr plagiogneiss datings point with the biggest possibility to the following main events of geological history of these rocks formation: 1) magmatic intrusion of plagiogranites in Vendian; Sm-Nd isochrone 691 ± 58 Ma also points to neoproterozoic age of the plagiogneiss initial substance; 2) the metamorphism of plagiogranites and its turning into plagiogneisses involved in early Ordovician (486 Ma); 3) the latest tectonothermal events (292 ± 23 Ma), fixed by Rb-Sr system are associated possibly with collision processes.…”
Get full text

Gypsum karst of the Baltic Republics by Paukstys B., Narbutas V.

“…In the north, within the Republic of Estonia, Ordovician and Silurian limestones and dolomites crop out, or are covered by glacial Quaternary sediments. …”
Get full text

Lithofacies palaeogeography as a guide to petroleum exploration by Feng Zengzhao, Bao Hongping, Jia Jinhua, Wang Yigang, Deng Xiuqin

“…These examples include the dolostone of the Lower Ordovician Majiagou Formation 5 in the Ordos area, the Donghe Sandstone of the Upper Devonian and Lower Carboniferous in the Tarim Basin, the reef of the Upper Permian Changxing Formation in the Sichuan Basin, the oolitic bank of the Lower Triassic Feixianguan Formation in the Sichuan Basin, and the lacustrine delta sediments and gravity flow sediments of the Middle and Upper Triassic Yanchang Formation in the Ordos Basin.…”
Get full text

COMPOSITION OF GOLD AND FORMATION CONDITIONS OF ORES FROM THE KOPTO HYDROTHERMAL DEPOSIT (NORTHEAST TUVA) by R.V. Kuzhuget, N.N. Ankusheva, Sh.N. Oorzhak, Yu.V. Butanaev

“…Gold mineralization is confined to granite-porphyry dikes of the Early Ordovician Early Tannuola complex and associated beresite-listvenite metasomatites. …”
Get full text

Examining abnormal Silurian trilobites from the Llandovery of Australia by Russell D.C. Bicknell, Patrick M. Smith

“…This indicates a possible change in the trophic position of trilobites when compared to Cambrian and Ordovician palaeoecosystems.…”
Get full text

Fine detection of collapse columns based on controlled source audio-frequency magnetotelluric method by REN Chenfeng, CHENG Jiulong, LIU Bin, XIN Chengtao, CHENG Peng, ZHANG Yuqi, JIANG Chenglin

“…The collapse column is mainly developed in the 6# upper coal seam near the Ordovician limestone, and the diameter is about 30 m at the corresponding 6# coal seam position(depth 395 m), and the diameter increases to the deep. …”
Get full text

Evolutionary dynamics of mycorrhizal symbiosis in land plant diversification by Frida A. A. Feijen, Rutger A. Vos, Jorinde Nuytinck, Vincent S. F. T. Merckx

“…It has long been hypothesized that the Glomeromycotina, the mycorrhizal symbionts of the majority of plants, facilitated colonization of land by plants in the Ordovician. This view was recently challenged by the discovery of mycorrhiza-like associations with Mucoromycotina in several early diverging lineages of land plants. …”
Get full text

A sparsely encrusted hardground with abundant Trypanites borings from the Llandovery of the Velise River, western Estonia (Baltica) by Olev Vinn, Ursula Toom

“…The Päärdu hardground is more sparsely encrusted than common for the Late Ordovician and Silurian hardgrounds, but this may be a characteristic feature of the hardgrounds of Baltica. …”
Get full text

Preserved appendages in a Silurian binodicope: implications for the evolutionary history of ostracod crustaceans by Siveter, DJ, Briggs, DEG, Siveter, DJ, Sutton, MD

“…A male specimen provides the first evidence of the appendages of Binodicopina, a major group of Palaeozoic ostracods comprising some 135 Ordovician to Permian genera. The appendage morphology of D. paparme, but not its shell, indicates that binodicopes belong to Podocopa. …”

Ostracods in the Palaeozoic? by Siveter, D

“…In the absence of soft parts the case that leperditicopids (Ordovician-Devonian) are ostracods remains uncertain. …”

Preserved appendages in a Silurian binodicope: implications for the evolutionary history of ostracod crustaceans by Siveter, DJ, Briggs, DEG, Siveter, DJ, Sutton, MD

“…A male specimen provides the first evidence of the appendages of Binodicopina, a major group of Palaeozoic ostracods comprising some 135 Ordovician to Permian genera. The appendage morphology of D. paparme, but not its shell, indicates that binodicopes belong to Podocopa. …”

Marine origin of retroviruses in the early Palaeozoic Era by Aiewsakun, P, Katzourakis, A

“…Our phylogenetic analyses suggest that this major retroviral lineage, and therefore retroviruses as a whole, have an ancient marine origin and originated together with, if not before, their jawed vertebrate hosts >450 million years ago in the Ordovician period, early Palaeozoic Era.…”

Global climate stabilisation by chemical weathering during the Hirnantian glaciation by von Strandmann, P, Desrochers, A, Murphy, M, Finlay, A, Selby, D, Lenton, T

“…Here we use lithium isotopes (δ7Li) to assess the impact of silicate weathering across a significant climate-cooling period, the end-Ordovician Hirnantian glaciation (~445 Ma). We find a positive δ7Li excursion, suggestive of a silicate weathering decline. …”

Reply to Dewey and Ryan Comment on Searle, MP (2021) ‘Tectonic evolution of the Caledonian orogeny in Scotland: a review based on the timing of magmatism, metamorphism and deformat... by Searle, MP

“…I argue that the Caledonian geology of Scotland can be explained by a Laurentia – Midland valley arc-microcontinent collision, progressing from NW-directed ophiolite obduction in the Late Cambrian to crustal thickening and regional metamorphism during the Ordovician and Silurian, across the Dalradian and Moine metamorphic rocks. …”

The late Palaeozoic relations between Gondwana and Laurussia by McKerrow, W, Mac Niocaill, C, Ahlberg, P, Clayton, G, Cleal, C, Eagar, R

“…There were several continental collisions: the Tornquist Sea (between Baltica and Avalonia) closed in Late Ordovician time, the Iapetus Ocean (between Laurentia and the newly merged continents of Baltica and Avalonia) closed in Silurian time, and the Rheic Ocean (between Avalonia and Gondwana and the separate parts of the Armorican Terrane Assemblage) closed (at least partially) towards the end of Early Devonian time. …”

Subphylums of Arthropoda / by Dowdell, Gertrudis, author 648561

“…They originated as marine animals, possibly in the Cambrian period, but the first confirmed chelicerate fossils, eurypterids, date from 445 million years ago in the Late Ordovician period. The surviving marine species include the four species of Xiphosurans (horseshoe crabs), and possibly the 1,300 species of Pycnogonida (sea spiders), if the latter are chelicerates. …”
Get full text