Article
Paleontology
Martina Aubrechtova, Vojtech Turek, Stepan Manda
Summary: This study describes two well-preserved cephalopod species of the order Tarphyceratida from the Ordovician of the Prague Basin. One species, Trocholites fugax, has been found in coeval strata of Iberia, France, and Bohemia, supporting the hypothesis of interchange of faunas between different regions during the Middle/Late Ordovician boundary. The other species, Trocholites chaloupkai sp. nov., is one of the stratigraphically youngest Trocholites known in peri-Gondwana.
ACTA PALAEONTOLOGICA POLONICA
(2023)
Article
Geosciences, Multidisciplinary
Zisang Huang, Zhongquan Li, Wenrui Shi, Xiyan Yang, Xingzhi Wang, Steven Young
Summary: This study reconstructs the sedimentary mechanisms of shale in the southern Sichuan Basin by combining logging, mineralogy, and geochemistry. The study found that the shale in the area can be divided into different sequences, which are influenced by factors such as volcanic eruption and glaciation, leading to different sedimentary environments and lithofacies. This has significant implications for the development and exploration of shale gas.
MARINE AND PETROLEUM GEOLOGY
(2023)
Article
Geography, Physical
Yi-long Liu, Ruo-ying Fan, Rui-wen Zong, Yi-ming Gong
Summary: This article reports a new species of caryocaridids from the Late Ordovician of Inner Mongolia, China, expanding the distribution of caryocaridids in the northern part of China. Morphological and morphometric studies on the specimens reveal different ontogenetic stages. The taphonomic features show in-situ and parautochthonous preservation. The Ordovician caryocaridids were likely stenothermic and preferred cool- to cold-water environments, displaying the polar emergence phenomenon.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Duo Wang, Zhidi Liu
Summary: This study investigates the influence of the lamina effect on the tensile strength of shallow marine shales and improves the existing Brazilian standard disc splitting method by selecting the Laminashale of the Upper Ordovician Wulalik Fm as the experimental object. The study determines the direction of crustal stress through the radial wave velocity anisotropy test and drills standard cores. The Brazilian standard disc splitting experiment was designed and carried out on Lamina shale with different loading angles. The results show that the presence of lamina makes the tensile strength of shallow marine shale exhibit significant anisotropy and the fracture surface morphology of standard discs varies greatly under different loading angles.
Review
Geography, Physical
James C. Lamsdell
Summary: Over the past century, palaeobiological studies have focused on understanding how evolutionary lineages occupy or are excluded from new regions of morphological, ecological, and geographic space. It is increasingly recognized that a hierarchical approach incorporating genealogical processes and external ecological factors is necessary to understand the mechanisms driving phenotypic change. The unresolved question remains whether the evolution of novel morphologies facilitates expansion to new environments (a developmental push mechanism) or whether ecological shifts lead to subsequent morphological change (an ecological pull mechanism).
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2021)
Article
Energy & Fuels
Yuping Wu, Chenglin Liu, Yongjun Liu, Hongwei Gong, Rizwan Sarwar Awan, Guoxiong Li, Qibiao Zang
Summary: The study of organic matter enrichment in a section of the Upper Ordovician Tanjianshan Group in the Qaidam Basin revealed elevated total organic carbon content, mature organic matter, and hot-arid paleoclimatic conditions. Factors such as paleoredox conditions and paleowater depth were found to play significant roles in the enrichment of organic matter in the rocks.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Ecology
Harriet B. Drage, David A. Legg, Allison C. Daley
Summary: This study describes the moulting behavior and adaptive characteristics of a species of extinct euarthropods called marrellomorphs found in the Early Ordovician Fezouata Shale Lagerstatte of Morocco. The research suggests that these marrellomorphs exhibited similar moulting behaviors to extant lobster-like arthropods, which could be attributed to their complex morphology and the need for extracting complex spines. This study expands our understanding of important characteristics of extinct euarthropods.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2023)
Article
Paleontology
Jana Bruthansova, Jiri Bruthans, Heyo Van Iten, Stepan Rak, Jana Schweigstillova
Summary: This study describes five quartzose sandstone slabs containing Anaconularia anomala from the Letna Formation in the Prague Basin. The slabs contain adjacent conulariids and other fossils buried in a single bedding plane. The investigated conulariids show strong alignment and suggest burial by unidirectional currents. The growth pattern of the conulariids does not indicate clonal budding.
Article
Geosciences, Multidisciplinary
Yanni Zhang, Rongxi Li, Hexin Huang, Tian Gao, Lei Chen, Bangsheng Zhao, Xiaoli Wu, Ahmed Khaled
Summary: The silica in the Wulalike shale mainly consists of biogenic and detrital silica, with a positive correlation between total organic carbon and biogenic silica, indicating a link to paleoproductivity. Biogenic silica is mainly distributed at the bottom of the formation, forming a rigid framework to improve shale hardness and brittleness, making it easier to fracture for shale gas extraction.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Geology
Christopher R. C. Paul, Ursula Toom
Summary: This study reexamined the structure of Cystoblastus and found discrepancies between previous descriptions and actual specimens. Attempt was made to identify plate homologies between glyptocystitoid and hemicosmitoid rhombiferans.
ESTONIAN JOURNAL OF EARTH SCIENCES
(2021)
Article
Geosciences, Multidisciplinary
Chaoyong Wang, Zaitian Dong, Xuehai Fu, Qing Chen, Xiaofan Liu, Mengmeng Tang, Zetang Wang
Summary: This study investigates the spatiotemporal variation and potential controlling factors of marine redox conditions in the Upper Yangtze Basin during the Late Ordovician to Early Silurian Transition, highlighting the potential control effects of sea level change, continental weathering, and upwelling on the development of euxinic water columns. The findings suggest that the development of anoxic water, especially euxinia, in the area exhibits obvious spatiotemporal heterogeneity, with different factors influencing the prevalence of ferruginous and euxinic water columns in different water depths.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Paleontology
Aram Bayet-Goll, Alfred Uchman, Mehdi Daraei, Carlos Neto de Carvalho
Summary: The abundant occurrence of Trichophycus venosus trace fossils in the Tremadocian-to-Floian siliciclastic deposits in central Iran indicates an increase in exploitation of offshore infaunal ecospace, which negatively affects the preservation of shallow-tier trace fossils, particularly those produced by trilobites. The development of the Crowded Trichophycus ichnofabric (CTI) suggests stable habitats with high food and oxygen content in muddy substrates above the storm wave base. The ethology and morphology of Trichophycus point to a combined dwelling-feeding activity of the resident producer, indicating an infaunalization related to the Great Ordovician Biodiversification Event.
Article
Evolutionary Biology
Jeffrey R. Thompson, Laura J. Cotton, Yves Candela, Manfred Kutscher, Mike Reich, David J. Bottjer
Summary: The echinoids of the order Bothriocidaroida represent an important phase in the diversification of sea urchins. Through detailed phylogenetic analyses and the description of a new species, Neobothriocidaris pentlandensis sp. nov., this study sheds light on the phylogenetic relationships, diversity dynamics, and paleobiogeographical distribution of the Bothriocidaroida. The findings suggest that Bothriocidaroids originated in the Dapingian or Darriwilian, diversified during the Darriwilian to Sandbian periods, and reached peak diversity in the Sandbian and Katian.
JOURNAL OF SYSTEMATIC PALAEONTOLOGY
(2022)
Article
Geography, Physical
Mark W. Hounslow, Samuel E. Harris, Krystian Wojcik, Jerzy Nawrocki, Kenneth T. Ratcliffe, Nigel H. Woodcock, Paul Montgomery
Summary: Magnetostratigraphic studies of the Ordovician provide evidence for the nature of core-mantle boundary interactions, and the new data contribute to a near-complete magnetic polarity chronostratigraphic scale through the Middle and Upper Ordovician. The magnetic signal is carried by both haematite and magnetite, with correlations between lithologies and local magnetic susceptibility, providing validation of a primary palaeomagnetic signal. The reversal frequencies for the mid and late Ordovician are estimated to be 1.7 and 1.5 Myr (-1) respectively.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2021)
Article
Geosciences, Multidisciplinary
Linna Zhang, Junxuan Fan, Bo Wang, Yuandong Zhang, Jianbo Liu, Hao Huang, Qing Chen
Summary: High-resolution, quantitative paleogeographical reconstruction based on geological big data and GIS is crucial for visualizing regional and global paleogeographical features and their evolution, as well as understanding the interaction of lithosphere, hydrosphere, and biosphere. This study collected and standardized a comprehensive dataset of 807 Ordovician sections in South China, and reconstructed lithofacies paleogeographical maps and stratigraphical thickness isopach maps for ten consecutive time intervals. Precise timing and processes of land-sea distribution and basin basement transformation were revealed, showing distinct paleogeographical processes among different terranes. The study recognized a new evolutionary process of the paleogeographical pattern in South China and provided insights into depositional centers, provenance regions, and the effects of tectonic movement and sea-level changes.
EARTH-SCIENCE REVIEWS
(2023)