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Journal articles on the topic 'Radiolaria, Fossil'

Author: Grafiati

Published: 4 June 2021

Last updated: 30 January 2023

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1

Casey, Richard E. "Radiolaria." Notes for a Short Course: Studies in Geology 18 (1987): 213–47. http://dx.doi.org/10.1017/s027116480000155x.

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Radiolaria are marine holoplanktonic animal-like protists belonging to the Superclass Actinopodea of the Subphylum Sarcodina. When biologists speak of radiolarians they usually mean the subgroup Acantharia that are common in nearshore waters and are sometimes involved in plankton blooms. When paleontologists speak of radiolarians they usually mean the subgroups preserved in the fossil record; the Polycystina (or polycystine) encompassing Spumellaria and Nassellaria, which possess solid opaline skeletal structures, and the Phaeodaria (or phaeodarians), which possess hollow skeletal structures of an admixture of silica and organic matter.

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2

Zhang, Lei, Taniel Danelian, Qinglai Feng, Thomas Servais, Nicolas Tribovillard, and Martial Caridroit. "On the Lower Cambrian biotic and geochemical record of the Hetang Formation (Yangtze Platform, south China): evidence for biogenic silica and possible presence of Radiolaria." Journal of Micropalaeontology 32, no. 2 (July 1, 2013): 207–17. http://dx.doi.org/10.1144/jmpaleo2013-003.

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Abstract. Research on Lower Cambrian siliceous sedimentary rocks is important for understanding the origin and early involvement of polycystine Radiolaria in the silica cycle. During our study, thin sections and HF acid processing of black cherts and shales from the Hetang Formation that crops out in the Xintangwu section (west Zhejiang Province, south China) were made. We report on the presence of siliceous spherical microfossils (possibly Radiolaria) associated with sponge spicules and acritarchs. Their size and the presence of residual spines on some spherical siliceous microfossils observed in both residues and thin sections of cherts from the top of Member ‘a’ of the Hetang Formation argue for the possible presence of radiolarians. Based on the Small Shelly Fossil assemblages reported in previous studies, this interval should be considered as Qiongzhusian (Atdabanian–Early Botomian) in age. Finally, the values of the Ge/Si ratio measured on black cherts of the Hetang Formation point to a biogenic origin of the silica.

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3

Stanek, J., and W. Kiessling. "Sectioning of radiolarians under continuous observation." Fossil Record 5, no. 1 (January 1, 2002): 45–49. http://dx.doi.org/10.5194/fr-5-45-2002.

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A new method to study the internal structure of fossil radiolarians in presented. The core of the method is (1) freezing the radiolarian in a drop of water using a Peltier module and (2) slicing the radiolarian with a specially equipped electric tooth-brush under an optical microscope. With this method the internal structure of diagenetically altered radiolarians can be studied even if internal sediment cannot be removed. <br><br> Eine neue Methode zur Analyse der Internstrukturen von Radiolarien wird vorgestellt. Die Methode beinhaltet (1) Einfrieren einzelner Radiolarien in einem Wassertropfen mit Hilfe eine Peltier-Elements und (2) Schleifen der Radiolarien mit Hilfe eine modifizierten elektrischen Zahnbürste unter einem Binokular. Mit dieser Methode ist es möglich Internstrukturen von Radiolarien zu untersuchen, selbst wenn diese diagenetisch verändert sind oder fest verbackenes Internsediment aufweisen. <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.20020050104" target="_blank">10.1002/mmng.20020050104</a>

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4

Izumi, Kentaro, and Kazuko Yoshizawa. "Star-shaped trace fossil and Phymatoderma from Neogene deep-sea deposits in central Japan: probable echiuran feeding and fecal traces." Journal of Paleontology 90, no. 6 (October 11, 2016): 1169–80. http://dx.doi.org/10.1017/jpa.2016.95.

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AbstractA co-occurrence of the ichnogenus Phymatoderma and a star-shaped horizontal trace fossil was discovered from Neogene deep-marine deposits (Misaki Formation, central Japan), and is described herein for the first time. Phymatoderma consists of a straight to slightly curved tunnel that shows first- or second-order branches. The tunnels are 5.30–27.25 mm in diameter and are filled with ellipsoidal pellets. The relatively well-preserved star-shaped trace fossil is a large horizontal structure (~18 cm×19 cm) that consists of at least 10 spokes with diameters ranging from 11.49–20.96 mm. As compared to modern analogous surface-feeding traces produced by abyssal echiuran worms and their burrow morphology, it is highly likely that the star-shaped trace fossil and Phymatoderma found from the Misaki Formation are feeding and fecal traces of ancient deep-sea echiurans, respectively. Difference in preservation potential between surface and subsurface traces may result in rare occurrence of star-shaped trace fossils as compared to Phymatoderma. Microscopic observation of the pelletal infill of Phymatoderma also reveals that the trace-maker fed on organic debris and microorganisms such as diatoms and radiolaria.

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5

Streiker, Scott, and Rachel Smith. "The NEST Laboratory: The Art of a Multi-User Facility." Microscopy Today 14, no. 6 (November 2006): 52–55. http://dx.doi.org/10.1017/s1551929500058909.

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Radiolaria are marine protozoa that have thrived in the world's oceans for millions of years. They are particularly unique among marine plankton in that they build silica skeletons, which have allowed them to be preserved in the fossil record. These skeletons are ornate and complex and often demonstrate perfect geometric form and symmetry. The complex and beautiful glass-like structures are visually interesting when examined with electron microscopy. These attributes, coupled with their availability, size, ease of mounting and preparation make them superb specimens for introducing students to the use of electron microscopy (EM).

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6

O'Connor, Barry. "Confocal Laser Scanning Microscopy: A New Technique for Investigating and Illustrating Fossil Radiolaria." Micropaleontology 42, no. 4 (1996): 395. http://dx.doi.org/10.2307/1485963.

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7

TRUBOVITZ, SARAH, JOHAN RENAUDIE, DAVID LAZARUS, and PAULA NOBLE. "Late Neogene Lophophaenidae (Nassellaria, Radiolaria) from the eastern equatorial Pacific." Zootaxa 5160, no. 1 (July 4, 2022): 1–158. http://dx.doi.org/10.11646/zootaxa.5160.1.1.

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Lophophaenidae is a clade of polycystine radiolarians that was highly abundant and diverse in the Late Neogene–Recent eastern equatorial Pacific (EEP). Despite their importance in fossil plankton assemblages, lophophaenids have been neglected because of their generally small size, complex morphology, and weak taxonomic framework. These challenges have left many lophophaenid concepts poorly defined or lacking formal description. Here we address this with a review of 101 lophophaenid taxa observed in EEP Middle Miocene–Recent marine sediments. We discuss existing lophophaenid genera Amphiplecta Haeckel 1881, Arachnocorallium Haeckel 1887, Arachnocorys Haeckel 1860, Botryopera Haeckel 1887, Ceratocyrtis Bütschli 1882, Lithomelissa Ehrenberg 1847, Lophophaena Ehrenberg 1847, and Peromelissa Haeckel 1881, including full species lists. We describe Pelagomanes n. gen., 23 new species: Amphiplecta kikimorae n. sp., Arachnocorys jorogumoae n. sp., Botryopera amabie n. sp., Botryopera babayagae n. sp., Botryopera bolotniki n. sp., Ceratocyrtis? chimii n. sp., Ceratocyrtis vila n. sp., Lithomelissa alkonost n. sp., Lithomelissa babai n. sp., Lithomelissa dybbuki n. sp., Lithomelissa sirin n. sp., Lophophaena arie n. sp., Lophophaena casperi n. sp., Lophophaena domovoi n. sp., Lophophaena gozui n. sp., Lophophaena ikiryo n. sp., Lophophaena ikota n. sp., Lophophaena kaonashii n. sp., Lophophaena leshii n. sp., Lophophaena rusalkae n. sp., Lophophaena shishigae n. sp., Lophophaena ushionii n. sp., and Pelagomanes ibburi n. sp., and one new subspecies, Arachnocorys pentacantha wanii n. subsp. In addition, we document 35 taxa in open nomenclature, and revise generic assignments of 10 species. The names of 32 previously-described species are upheld, but with clarified synonymies, discussion, and illustrations. This work contributes a practical framework for identifying tropical Late Neogene–Recent lophophaenid taxa, and demonstrates their rich morphological diversity.

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Smits, Peter, and Seth Finnegan. "How predictable is extinction? Forecasting species survival at million-year timescales." Philosophical Transactions of the Royal Society B: Biological Sciences 374, no. 1788 (November 4, 2019): 20190392. http://dx.doi.org/10.1098/rstb.2019.0392.

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A tenet of conservation palaeobiology is that knowledge of past extinction patterns can help us to better predict future extinctions. Although the future is unobservable, we can test the strength of this proposition by asking how well models conditioned on past observations would have predicted subsequent extinction events at different points in the geological past. To answer this question, we analyse the well-sampled fossil record of Cenozoic planktonic microfossil taxa (Foramanifera, Radiolaria, diatoms and calcareous nanoplankton). We examine how extinction probability varies over time as a function of species age, time of observation, current geographical range, change in geographical range, climate state and change in climate state. Our models have a 70–80% probability of correctly forecasting the rank order of extinction risk for a random out-of-sample species pair, implying that determinants of extinction risk have varied only modestly through time. We find that models which include either historical covariates or account for variation in covariate effects over time yield equivalent forecasts, but a model including both is overfit and yields biased forecasts. An important caveat is that human impacts may substantially disrupt range-risk dynamics so that the future will be less predictable than it has been in the past. This article is part of a discussion meeting issue ‘The past is a foreign country: how much can the fossil record actually inform conservation?’

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9

Zeiss, Arnold. "The Upper Jurassic of Europe: its subdivision and correlation." Geological Survey of Denmark and Greenland (GEUS) Bulletin 1 (October 28, 2003): 75–114. http://dx.doi.org/10.34194/geusb.v1.4649.

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In the last 40 years, the stratigraphy of the Upper Jurassic of Europe has received much attention and considerable revision; much of the impetus behind this endeavour has stemmed from the work of the International Subcommission on Jurassic Stratigraphy. The Upper Jurassic Series consists of three stages, the Oxfordian, Kimmeridgian and Tithonian which are further subdivided into substages, zones and subzones, primarily on the basis of ammonites. Regional variations between the Mediterranean, Submediterranean and Subboreal provinces are discussed and correlation possibilities indicated. The durations of the Oxfordian, Kimmeridgian and Tithonian Stages are reported to have been 5.3, 3.4 and 6.5 Ma, respectively. This review of the present status of Upper Jurassic stratigraphy aids identification of a number of problems of subdivision and definition of Upper Jurassic stages; in particular these include correlation of the base of the Kimmeridgian and the top of the Tithonian between Submediterranean and Subboreal Europe. Although still primarily based on ammonite stratigraphy, subdivision of the Upper Jurassic is increasingly being refined by the incorporation of other fossil groups; these include both megafossils, such as aptychi, belemnites, bivalves, gastropods, brachiopods, echinoderms, corals, sponges and vertebrates, and microfossils such as foraminifera, radiolaria, ciliata, ostracodes, dinoflagellates, calcareous nannofossils, charophyaceae, dasycladaceae, spores and pollen. Important future developments will depend on the detailed integration of these disparate biostratigraphic data and their precise combination with the abundant new data from sequence stratigraphy, utilising the high degree of stratigraphic resolution offered by certain groups of fossils. This article also contains some notes on the recent results of magnetostratigraphy and sequence chronostratigraphy.

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10

Lazarus, Dave. "Morphometric studies of radiolarian evolution." Paleontological Society Special Publications 6 (1992): 178. http://dx.doi.org/10.1017/s2475262200007383.

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Radiolarians are the most diverse of the 4 major fossil forming plankton groups, with several hundred living species, and an equally diverse range of biologic specializations for planktonic existence. Studies of radiolarian evolution are mostly from the Cenozoic, where the opaline silica skeletons of radiolarians are well preserved in most areas of the world's oceans. Cenozoic radiolarian skeletons are mostly too small (50-150 μm) and delicate to easily manipulate individually. Washed sieved skeletons are strewn at random orientations onto glass microslides and viewed in transmitted light. At the required magnifications, most skeletons cannot be viewed in their entirety within a single focus-plane. Many (perhaps the majority) of taxonomic characters in radiolarians are not visible in the skeleton outline, but are internal. These characteristics make normal image analysis techniques more difficult to employ. Computer assisted manual digitizers (one version working in 3 dimensions) have sometimes been used to measure skeletons. Distance, angle, area, and shape outline measurements have all been used to quantify radiolarian morphology.Radiolarian skeletal growth is determinate, and relatively little ontogenetic or within-population allometric variation is seen. Geographic variation in radiolarian species morphology is common, but little studied. Perhaps due to the effort involved, most ordinary taxonomic work does not employ morphometric data: its use has largely been in species-level evolutionary studies. Phyletic trends in size, shape, and in other characters have long been used to delineate stratigraphically useful chronospecies, and some of these anagenetic series have been morphometrically measured. Cladogenesis has also been morphometrically quantified in a few cases. Most studies of both cladogenesis and anagenetic evolution have documented gradual rates of morphologic change.Integrated studies of paleogeographic variation and temporal change are still needed, as is better information on modern radiolarian biology. Much more efficient measurement tools are also needed, to handle the very large number of specimens required by integrated studies.

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11

Xiping, Dong, Andrew H. Knoll, and Jere H. Lipps. "Late Cambrian Radiolaria from Hunan, China." Journal of Paleontology 71, no. 5 (September 1997): 753–58. http://dx.doi.org/10.1017/s002233600003571x.

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Well-preserved polycystine radiolarians, representing a new species in the family Entactiniidae, were recovered from subtidal micrites and bioclastic micrites of the Upper Cambrian (Glyptagnostus reticulatustrilobite zone) Bitiao Formation, western Hunan, China. Confirming earlier, questionable reports of Cambrian Radiolaria, these fossils place the first appearance of the group somewhat before its Ordovician emergence as a principal constituent of the oceanic silica cycle, but long after the Proterozoic diversification of protists.

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12

Noble, P. J., and J. C. Aitchison. "Status of Ordovician and Silurian Radiolarian Studies in North America." Short Courses in Paleontology 8 (1995): 19–30. http://dx.doi.org/10.1017/s2475263000001409.

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Polycystine radiolaria that produce siliceous tests are known to range from Cambrian to Holocene. They have proven to be enormously useful in providing age control for siliceous marine sequences of Middle Devonian and younger ages, particularly for cherts and shales that are commonly devoid of other biostratigraphically useful fossils. The utility of radiolarian biostratigraphy became widely recognized in the 1970s and 1980s when it was applied in dating deformed marine siliceous sequences in orogenic belts around the world, most notably in Cordilleran North America and other areas along the Pacific rim (e.g., Jones and Murchey, 1986; Aitchison and Murchey, 1992; Ichikawa et al., 1990).

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13

Kocsis, Ádám T., Wolfgang Kiessling, and József Pálfy. "Radiolarian biodiversity dynamics through the Triassic and Jurassic: implications for proximate causes of the end-Triassic mass extinction." Paleobiology 40, no. 4 (2014): 625–39. http://dx.doi.org/10.1666/14007.

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Within a ∼60-Myr interval in the Late Triassic to Early Jurassic, a major mass extinction took place at the end of Triassic, and several biotic and environmental events of lesser magnitude have been recognized. Climate warming, ocean acidification, and a biocalcification crisis figure prominently in scenarios for the end-Triassic event and have been also suggested for the early Toarcian. Radiolarians, as the most abundant silica-secreting marine microfossils of the time, provide a control group against marine calcareous taxa in testing selectivity and responses to changing environmental parameters. We analyzed the origination and extinction rates of radiolarians, using data from the Paleobiology Database and employing sampling standardization, the recently developed gap-filler equations and an improved stratigraphic resolution at the substage level. The major end-Triassic event is well-supported by a late Rhaetian peak in extinction rates. Because calcifying and siliceous organisms appear similarly affected, we consider global warming a more likely proximate trigger of the extinctions than ocean acidification. The previously reported smaller events of radiolarian turnover fail to register above background levels in our analyses. The apparent early Norian extinction peak is not significant compared to the long-term trajectory, and is probably a sampling artifact. The Toarcian Oceanic Anoxic Event, previously also thought to have caused a significant radiolarian turnover, did not significantly affect the group. Radiolarian diversity history appears unique and complexly forced, as its trajectory parallels major calcareous fossil groups at some events and deviates at others.

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14

Culver, Stephen J. "Evolution Caught in the Act: Evidence from Microfossil Morphology." Paleontological Society Special Publications 11 (2002): 127–38. http://dx.doi.org/10.1017/s2475262200009862.

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Microfossils are of prime importance in documenting patterns of evolution due to their great abundance (often tens of thousands to millions of specimens in a hand sample) and widespread distribution (in both time and space) in the fossil record. The term “microfossil” is often used for paleontological material that requires a microscope for its study, no matter what its biological affinities. For the purposes of this article we will be looking at the remains of protists (single-celled organisms). The several examples I discuss in this chapter are of three groups of planktonic (floating) protists: the calcareous nannoplankton (tiny plant-like protists whose single cell is covered in minute calcitic scales), the radiolaria (animal-like protists with siliceous shells), and the planktonic foraminifera (animal-like protists with calcitic shells). These organisms have been the subject of extensive study because the material from which they are often extracted, cores of deep-sea sediments, are usually comprised of a more complete sedimentological record (i.e., have fewer breaks) than shallow shelf deposits. Hypotheses of evolutionary history have been constructed for many groups (lineages) of microfossils using specimens from deep-sea cores. Ancestor-descendent relationships have been recognized by tracking shape and form (morphologic) changes through time. This approach to reconstruction of evolutionary history provides an empirical record of morphologic evolution; that is, a record based on observations.

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15

Culver, Stephen J. "Evolution Caught in the Act: Evidence from Microfossil Morphology." Paleontological Society Special Publications 9 (1999): 155–70. http://dx.doi.org/10.1017/s2475262200014064.

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Microfossils are of prime importance in documenting patterns of evolution due to their great abundance (often tens of thousands to millions of specimens in a hand sample) and widespread distribution (in both time and space) in the fossil record. The term “microfossil” is often used for paleontological material that requires a microscope for its study, no matter what its biological affinities. For the purposes of this article we will be looking at the remains of protists (single-celled organisms). The several examples I discuss in this chapter are of three groups of planktonic (floating) protists, the calcareous nannoplankton (tiny plant-like protists whose single cell is covered in minute calcitic scales), the radiolaria (animal-like protists with siliceous shells) and the planktonic foraminifera (animal-like protists with calcitic shells). These organisms have been the subject of extensive study because the material from which they are often extracted, cores of deep-sea sediments, are usually comprised of a more complete sedimentological record (i.e., fewer breaks) than shallow shelf deposits. Hypotheses of evolutionary history have been constructed for many groups (lineages) of microfossils using specimens from deep-sea cores. Ancestor-descendent relationships have been recognized by tracking shape and form (morphologic) changes through time. This approach to reconstruction of evolutionary history provides an empirical record of morphologic evolution; that is, a record based on observations.

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16

Etherington, Raymond L., and Ronald L. Austin. "Note on the use of hydrofluoric acid for the recovery of conodonts from Ordovician cherts in the Southern Uplands of Scotland and the significance of the conodonts." Journal of Micropalaeontology 12, no. 2 (December 1, 1993): 194. http://dx.doi.org/10.1144/jm.12.2.194.

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Abstract. Procedures have been described for the recovery of conodonts from cherts by dissolution in hydrofluoric acid (see Stone, 1987 for a review), but this technique rarely has been applied. Cherts are more widely distributed in southern Scotland than are limestones which have been the focus of most research on conodonts. The HF technique thus opens a new and possibly more widely applicable avenue for conodont research for southern Scotland than the traditional methods.Ordovician conodonts on the surfaces of red cherts were reported from several localities near Peebles by Lamont and Lindström (1957), and the same authors found conodonts in yellow silt-stones interbedded with cherts south of Abington. These localities were visited to obtain samples that we believed to have a high probability of containing conodonts in order to test the HF procedure on Scottish rocks. We found conodonts in red rocks like those reported by Lamont and Lindström at their Noblehouse and Ruddenleys localities. Unfortunately the rocks there are not cherts as they reported, but are red mudstones instead. Such rocks are not amenable to the HF techniques.Microscopic examination of grey cherts collected loose below Ravengill Burn (Grid Reference 26/921199, one of Lamont and Lindstrom’s localities) showed that they contained radiolaria, a common fossil in the cherts of Scotland. Small pieces of these cherts, aggregating about 50 g, were placed in dilute (10% by volume) HF. The acid was decanted episodically after periods ranging from 8 hours to 73 hours, and the undissolved material was wet-screened through a . . .

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17

Ślączka, Andrzej, M. Gasiñski, Marta Bąk, and Godfrid Wessely. "The clasts of Cretaceous marls in the conglomerates of the Konradsheim Formation (Pöchlau quarry, Gresten Klippen Zone, Austria)." Geologica Carpathica 60, no. 2 (April 1, 2009): 151–64. http://dx.doi.org/10.2478/v10096-009-0010-7.

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The clasts of Cretaceous marls in the conglomerates of the Konradsheim Formation (Pöchlau quarry, Gresten Klippen Zone, Austria)Investigations were carried out on foraminiferids and radiolaria from redeposited clasts within the conglomerates of the Konradsheim Formation (Gresten Klippen Zone) in the area of the Pöchlau hill, east of Maria Neustift. These shales and marls are of Middle to Late Jurassic and Early Cretaceous age. In the latter clasts, foraminiferal assemblages withTritaxiaex gr.gaultinaas well as radiolaria speciesAngulobracchia portmanniBaumgartner,Dictyomitra communis(Squinabol),Hiscocapsa asseni(Tan),Pseudodictyomitra lodogaensisPessagno,Pseudoeucyrtis hanni(Tan),Rhopalosyringium fossile(Squinabol) were found. In one block from the uppermost part of the sequence there is an assemblage withCaudammina(H)gigantea, Rotalipora appenninicaandGlobotruncana bulloides.However, the brecciated character of this block and occurrence near a fault suggest that it was probably wedged into the conglomerates of the Konradsheim Formation during tectonic movements. In pelitic siliceous limestones below the Konradsheim Limestone radiolarian assemblages of Middle Callovian to Early Tithonian age were found. They enable correlation with the Scheibbsbach Formation. In a marly sequence, above the conglomeratic limestone, the foraminiferal assemblages contain taxa from mid-Cretaceous up to Paleocene. The present biostratigraphic investigation confirmed the previous stratigraphic assignments and imply clearly that the sedimentation of deposits similar to the Konradsheim Formation also occurred at the end of the Early Cretaceous and deposition of conglomeratic limestones within the Gresten Klippen Zone, and especially within the Konradsheim Formation, was repeated several times during the Late Jurassic and Early Cretaceous.

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18

Goričan, Špela, Martin Đaković, Peter O. Baumgartner, Hans-Jürgen Gawlick, Tim Cifer, Nevenka Djerić, Aleksander Horvat, Anja Kocjančič, Duje Kukoč, and Milica Mrdak. "Mesozoic basins on the Adriatic continental margin – a cross-section through the Dinarides in Montenegro / Mezozojski bazeni na kontinentalnem robu Jadranske plošče – presek čez Dinaride v Črni gori." Folia biologica et geologica 63, no. 2 (September 7, 2022): 85–150. http://dx.doi.org/10.3986/fbg0099.

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The Dinarides, together with the Albanides and Hellenides, preserve stratigraphic successions derived from the eastern margin of the Adriatic microplate and remnants of ophiolites obducted from the Maliac-Vardar branch of the Neotethys Ocean. The main stages in the Mesozoic geodynamic history are: 1) rifting leading to opening of the Maliac Ocean in the Late Anisian, 2) onset of an east-dipping intra-oceanic subduction in the Early-Middle Jurassic and sea-floor spreading in a supra-subduction setting (Vardar Ocean), 3) formation of ophiolitic mélanges in trench-like basins, westward obduction of young supra-subduction ophiolites in the Middle-Late Jurassic and accumulation of flysch-type deposits in foreland basins in the latest Jurassic to Early Cretaceous, 4) subaerial exposure of the newly formed nappes followed by middle to Late Cretaceous transgression, and 5) continental collision in the Maastrichtian and Paleogene. On the continental margin, the Middle Triassic to Early Jurassic extension created a complex horst-and-graben geometry that is apparent in the stratigraphic record. The present day NW-SE striking tectonic units are in rough accordance with the Mesozoic paleogeography. Hence, the inferred configuration for the most complete SW to NE transect through Montenegro and Serbia is as follows: The Dalmatian Carbonate Platform, the Budva Basin, the High Karst Carbonate Platform, the Bosnian Basin, the Durmitor High, the Lim Basin, the Drina-Ivanjica High, and the deep-marine distal continental-margin domain. We present a short description of the stratigraphy for these tectonic/paleogeographic units and discuss their possible connection with other units of the Dinarides and Hellenides. The field guide focuses on deep-water deposits, in which radiolarians are the crucial tool for dating. We describe the complete Mesozoic succession of the Budva Zone, the Middle Triassic pelagic episode of the High Karst Zone, the Upper Triassic and Jurassic pelagic rocks of the Lim Zone and two localities with radiolarites associated with ophiolites. The largest part of the guide is devoted to the Budva Zone, a deeply rifted trough in the continuation of the Pindos Basin. The Budva Zone with its external location in the Dinaric orogen was a site of continuous pelagic sedimentation from the Middle Triassic to the end Cretaceous. Radiolarites characterize the Middle Triassic, Hettangian–Sinemurian, Aalenian to Tithonian, and Hauterivian–Barremian to lower Turonian; pelagic limestones prevail in the Upper Triassic, Berriasian–Valanginian and upper Turonian to Maastrichtian. Calcareous turbidites from the adjacent High Karst Carbonate Platform are interstratified in all units and completely replace radiolarites in the Pliensbachian. Pelagic sequences also occur in the High Karst Zone, but are confined to the Middle Triassic syn- and early post-rift deposits. A 20 m thick unit of Middle Triassic nodular limestone and radiolarite within shallow-water carbonates is a typical example. More internally, the western Ćehotina Subzone of the Lim Zone records pelagic sedimentation from the Middle Triassic to early Cretaceous, when synorogenic mixed carbonate-siliciclastic deposition began. This zone has been less investigated than the Budva Zone. A 100 m thick Norian to Rhaetian succession of limestone with chert nodules is dated with conodonts. A Callovian-early Oxfordian age of lime-free cherts is determined with radiolarians. The Mihajlovići Subzone that may have been part of the Drina-Ivanjica paleogeographic unit shows Triassic shallow-water carbonates and a Jurassic deepening upward sequence ending with Oxfordian radiolarites. The last two field-trip stops show upper Bathonian-lower Callovian radiolarites in an ophiolitic mélange and upper Anisian radiolarites in direct contact with basalt. These ages, obtained in the south-westernmost ophiolite remnants of the Dinarides, agree with previously documented ophiolite ages in the wider region. In comparison with the Southern Alps and the Apennines, pelagic deposits of the Dinarides are characterized by an earlier onset and considerably higher proportions of silica with respect to carbonate throughout the Mesozoic. The Dinaric basins were connected with the central Neotethys, where the high fertility of surface waters enabled radiolarite formation since the oceanisation (Anisian or earlier) until the early Late Cretaceous, when planktonic foraminifera and calcareous nannoplankton began to dominate worldwide. Key words: Dinarides, Neotethys, radiolarites, continental margin, ophiolitic mélange IZVLEČEK V Dinaridih, Albanidih in Helenidih so ohranjena stratigrafska zaporedja vzhodnega roba Jadranske mikroplošče in ostanki ofiolitov, narinjenih na kontinent iz oceana Maliak-Vardar, ki je bil del Neotetide. Glavne stopnje v mezozojski geodinamični evoluciji tega ozemlja so bile: 1) rifting, ki je v zgornjem aniziju privedel do odprtja oceana Maliak, 2) v spodnji do srednji juri začetek intraoceanske subdukcije in raztezanje oceanskega dna v suprasubdukcijskem okolju Vardarskega oceana, 3) v srednji do zgornji juri formacija ofiolitnega melanža v jarkom podobnih bazenih in obdukcija mladih suprasubdukcijskih ofiolitov proti zahodu ter na koncu jure in v spodnji kredi akumulacija flišnih sedimentov v predgornih bazenih, 4) emerzija novo nastalih pokrovov in nato transgresija v srednji do zgornji kredi, 5) kolizija kontinentov v maastrichtiju in paleogenu. Kontinentalni rob se je med ekstenzijo od srednjega triasa do spodnje jure diferenciral na horste in grabne, kar se odraža v stratigrafskem zapisu. Današnje NW-SE usmerjene tektonske enote v Dinaridih se v grobem ujemajo z mezozojsko paleogeografijo, iz česar sklepamo, da je bila konfiguracija kontinentalnega roba v prečnem preseku čez Črno goro in Srbijo naslednja: Dalmatinska karbonatna platforma, Budvanski bazen, karbonatna platforma Visokega Krasa, Bosanski bazen, Durmitorski prag, Limski bazen, prag Drina-Ivanjica in globokomorski distalni kontinentalni rob. V članku je najprej na kratko opisan stratigrafski razvoj tektonskih oziroma paleogeografskih enot tega preseka in domnevna povezava z drugimi enotami v Dinaridih in Helenidih. V nadaljevanju so opisane ogledne točke ekskurzije s poudarkom na globokomorskih sedimentnih kamninah, ker so za določanje starosti teh kamnin radiolariji najpomembnejši in pogosto edini fosili. Podrobno predstavljamo celotno mezozojsko zaporedje Budvanske cone, srednjetriasno pelagično epizodo v coni Visokega Krasa, zgornjetriasne in jurske pelagične kamnine Limske cone in dve lokaliteti z radiolariti v ofiolitih. Največji del vodnika je posvečen Budvanski coni v Zunanjih Dinaridih. V mezozoiku je bila ta cona globokomorski jarek v nadaljevanju bazena Pindos s kontinuirano pelagično sedimentacijo od srednjega triasa do konca krede. Radiolariti so značilni za obdobje srednjega triasa, hettangija in sinemurija, aalenija do tithonija ter hauterivija-barremija do spodnjega turonija. Pelagični apnenci prevladujejo v zgornjem triasu, berriasiju in valanginiju ter od zgornjega turonija do maastrichtija. Karbonatni turbiditi, prinešeni s sosednje karbonatne platforme Visokega Krasa, so interstratificirani v vseh formacijah, v pliensbachiju pa prevladujejo in popolnoma izpodrinejo pelagične sedimente. Pelagična zaporedja v coni Visokega Krasa so omejena na sinriftne in zgodnje postriftne sedimente. Kot tipičen primer predstavljamo 20 m debelo zaporedje srednjetriasnih gomoljastih apnencev in radiolaritov znotraj plitvovodnih karbonatov. V bolj interni Limski coni je za podcono Ćehotina značilna pelagična sedimentacija od srednjega triasa do začetka krede, ko so se začeli odlagati sinorogeni mešani karbonatno-siliciklastični sedimenti. Stratigrafsko zaporedje te podcone do sedaj ni bilo podrobneje proučeno. V članku je prvič datiran 100 m debel profil apnencev z gomolji roženca, ki smo ga s konodonti uvrstili v norij in retij. Z radiolariji smo dokazali callovijsko do spodnjeoksfordijsko starost plastovitih rožencev brez karbonata. V podconi Mihajlovići je stratigrafski razvoj podoben kot v enoti Drina-Ivanjica. Triasnim plitvovodnim karbonatom sledijo jurski apnenci, ki kažejo na postopno poglabljanje sedimentacijskega okolja. Zaporedje se konča z oxfordijskimi radiolariti. V Črni gori so ohranjeni najbolj jugozahodno ležeči ostanki ofiolitov v Dinaridih. Zadnji dve točki prikazujeta bathonijske do spodnjecallovijske radiolarite v ofiolitnem melanžu in zgornjeanizijske radiolarite v kontaktu z bazaltom. Te starosti se ujemajo z do sedaj znanimi datacijami v ofiolitih širše regije. V primerjavi z Južnimi Alpami in Apenini je za pelagične sedimente Dinaridov značilno, da so se začeli odlagati prej in da so skozi ves mezozoik vsebovali znatno višji delež kremenice glede na karbonat. Dinarski bazeni so bili povezani s centralno Neotetido, kjer je visoka produktivnost površinskih voda omogočala nastanek radiolaritov od oceanizacije (v aniziju ali še prej) do sredine zgornje krede, ko so po vsem svetu začeli prevladovati foraminifere in kalcitni nanoplankton. Ključne besede: Dinaridi, Neotetida, radiolariti, kontinentalni rob, ofiolitni melanž

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Orchard, M. J., F. Cordey, L. Rui, E. W. Bamber, B. Mamet, L. C. Struik, H. Sano, and H. J. Taylor. "Biostratigraphic and biogeographic constraints on the Carboniferous to Jurassic Cache Creek Terrane in central British Columbia." Canadian Journal of Earth Sciences 38, no. 4 (April 1, 2001): 551–78. http://dx.doi.org/10.1139/e00-120.

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Conodonts, radiolarians, foraminiferids, and corals provide constraints on the geology and tectonics of the Nechako region. They also support the notion that the Cache Creek Terrane is allochthonous with respect to the North American craton. The 177 conodont collections, assigned to 20 faunas, range in age from Bashkirian (Late Carboniferous) to Norian (Late Triassic); 70 radiolarian collections representing 12 zones range from Gzhelian (Late Carboniferous) to Toarcian (Early Jurassic); 335 collections assigned to 11 fusulinacean assemblages (with associated foram-algal associations) range from Bashkirian to Wordian (Middle Permian); and two coral faunas are of Bashkirian and Wordian age. The fossils document a long but sporadic history of sedimentary events within the Cache Creek Complex that included two major carbonate buildups in the Late Carboniferous (Pope limestone) and Middle Permian (Copley limestone), punctuated by intervening Early Permian deepening; basaltic eruptions during the mid Carboniferous and mid Permian; the onset of oceanic chert sedimentation close to the CarboniferousPermian boundary and its persistence through the Late Triassic (Sowchea succession); latest Permian and Early Triassic mixed clastics and volcanics (Kloch Lake succession); Middle and Late Triassic reworking of carbonates (Whitefish limestone), including cavity fill in older limestones (Necoslie breccia), and fine-grained clastic sedimentation extending into the Early Jurassic (Tezzeron succession). Tethyan, eastern Pacific, and (or) low-latitude biogeographic attributes of the faunas are noted in the Gzhelian (fusulines), Artinskian (conodonts, fusulines), Wordian (fusulines, corals, conodonts), and Ladinian (conodonts, radiolarians). The Cache Creek Terrane lay far to the west of the North American continent during these times.

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Danelian, Taniel, Patrick De Wever, and Michel Durand-Delga. "Revised radiolarian ages for the sedimentary cover of the Balagne ophiolite (Corsica, France). Implications for the palaeoenvironmental evolution of the Balano-Ligurian margin." Bulletin de la Société Géologique de France 179, no. 3 (May 1, 2008): 289–96. http://dx.doi.org/10.2113/gssgfbull.179.3.289.

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Abstract The age of radiolarites covering the Balagne ophiolite is reassessed based on new and revised radiolarian fossil evidence. The oldest radiolarian cherts are dated as upper Bathonian-lower Callovian in two tectonic units: San Colombano and Novella. These are amongst the oldest ages available so far from ophiolites of the Ligurian ocean. An important stratigraphic gap, spanning the Callovian-early Kimmeridgian interval, is specified between radiolarites and the overlying (and locally gullying) San Colombano shallow-water limestones (sub-unit I). We can now specify that radiolarian ooze accumulated until the late Kimmeridgian in the distal parts of the Balagne margin (sub-unit SC III and Novella unit), while fragments of Hercynian basement fell into the Balagne basin during the late Kimmeridgian-Tithonian.

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Prössl, Klaus F., and Joachim R. Grösser. "Pyritized microfossils in palynological slides from the Late Cretaceous of Colombia." Journal of Micropalaeontology 28, no. 1 (May 1, 2009): 45–52. http://dx.doi.org/10.1144/jm.28.1.45.

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Abstract. Palynological investigations of Late Cretaceous to Tertiary sediments of the Andes in Colombia yielded some distinct groups of palynoclasts recovered as pyritized remains of diatoms, radiolaria and foraminifera. The different processes of pyritization are illustrated and the palaeontological use of these fossils is discussed. Techniques for investigating such opaque microfossils are also suggested.

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Conway Morris, S., and Chen Menge. "Blastulospongia polytreta n. sp., an enigmatic organism from the Lower Cambrian of Hubei, China." Journal of Paleontology 64, no. 1 (January 1990): 26–30. http://dx.doi.org/10.1017/s0022336000042207.

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Blastulospongia is an enigmatic siliceous fossil with affinities proposed amongst both the sphinctozoan-grade sponges and radiolarians. Blastulospongia polytreta n. sp. extends the record of this genus into the Lower Cambrian (Shuijingtuo Formation) and represents its first occurrence in China (Taishanmiao section, Hubei Province). It differs from previously described species in size and pore spacing. The first evidence for benthic attachment is presented. A relationship with sphinctozoan-grade sponges is considered unlikely, but firm support for a place in the radiolarians is lacking.

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NAKASEKO, Kojiro. "An essential role of radiolarian fossils in biostratigraphy." Journal of Geography (Chigaku Zasshi) 93, no. 7 (1985): 508–14. http://dx.doi.org/10.5026/jgeography.93.7_508.

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Haslett, Simon K. "Annotated bibliography of fossil radiolarian occurrences in the British Isles." Proceedings of the Geologists' Association 107, no. 4 (January 1996): 281–86. http://dx.doi.org/10.1016/s0016-7878(96)80015-0.

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Pascher, K. M., C. J. Hollis, S. M. Bohaty, G. Cortese, R. M. McKay, H. Seebeck, N. Suzuki, and K. Chiba. "Expansion and diversification of high-latitude radiolarian assemblages in the late Eocene linked to a cooling event in the southwest Pacific." Climate of the Past 11, no. 12 (December 7, 2015): 1599–620. http://dx.doi.org/10.5194/cp-11-1599-2015.

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Abstract. The long-term cooling trend from middle to late Eocene was punctuated by several large-scale climate perturbations that culminated in a shift to "icehouse" climates at the Eocene–Oligocene transition. We present radiolarian micro-fossil assemblage and foraminiferal oxygen and carbon stable isotope data from Deep Sea Drilling Project (DSDP) sites 277, 280, 281, and 283 and Ocean Drilling Project (ODP) Site 1172 to identify significant oceanographic changes in the southwest Pacific through this climate transition (~ 40–30 Ma). We find that the Middle Eocene Climatic Optimum at ~ 40 Ma, which is truncated but identified by a negative shift in foraminiferal δ18O values at Site 277, is associated with a small increase in radiolarian taxa with low-latitude affinities (5 % of total fauna). In the early late Eocene at ~ 37 Ma, a positive oxygen isotope shift at Site 277 is correlated with the Priabonian Oxygen Isotope Maximum (PrOM). Radiolarian abundance, diversity, and preservation increase within this cooling event at Site 277 at the same time as diatom abundance. A negative δ18O excursion above the PrOM is correlated with a late Eocene warming event (~ 36.4 Ma). Radiolarian abundance and diversity decline within this event and taxa with low-latitude affinities reappear. Apart from this short-lived warming event, the PrOM and latest Eocene radiolarian assemblages are characterised by abundant high-latitude taxa. High-latitude taxa are also abundant during the late Eocene and early Oligocene (~ 38–30 Ma) at DSDP sites 280, 281, 283 and 1172 and are associated with very high diatom abundance. We therefore infer a northward expansion of high-latitude radiolarian taxa onto the Campbell Plateau in the latest Eocene. In the early Oligocene there is an overall decrease in radiolarian abundance and diversity at Site 277, and diatoms are scarce. These data indicate that, once the Antarctic Circumpolar Current was established in the early Oligocene (~ 30 Ma), a frontal system similar to present day developed, with nutrient-depleted Subantarctic waters bathing the area around DSDP Site 277, resulting in a more restricted siliceous plankton assemblage.

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Dzulkafli, Muhammad Ashahadi, Che Aziz Ali, and Mohd Basril Iswadi Basori. "Radiolaria Perm Awal daripada Ladang Harmoni, Pos Blau, Baratdaya Kelantan." Sains Malaysiana 51, no. 7 (July 31, 2022): 1979–92. http://dx.doi.org/10.17576/jsm-2022-5107-03.

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Radiolaria berusia Sakmarian Awal (Perm Awal) ditemui dalam jujukan rijang yang berselang lapis dengan batu lumpur bertuf daripada Ladang Harmoni, Pos Blau, Gua Musang. Sebanyak 21 spesies radiolaria telah dikenal pasti, terdiri daripada Pseudoalbaillella lomentaria Ishiga & Imoto, Pseudoalbaillella sakmarensis (Kozur), Pseudoalbaillella scalprata postscalprata Ishiga, Pseudoalbaillella cf. internata Wang, Pseudoalbaillella sp. A, Pseudoalbaillella sp. B, Hegleria mammilla (Sheng & Wang), Hegleria sp. A, Ruzhencevispongus rotundus Feng, Ruzhencevispongus girtyi Nazarov & Ormiston, Ruzhencevispongus triradiatus Wang, Latentifistula patagilaterala Nazarov & Ormiston, Latentifistula texana Nazarov & Ormiston, Latentifistula crux Nazarov & Ormiston, Latentibifistula triacanthophora Nazarov & Ormiston, Quinqueremis robusta Nazarov & Ormiston, Pseudotormentus kamigoriensis De Wever & Caridroit, Ormistonella robusta De Wever & Caridroit, Copicyntra sp., Copielintra sp. dan Stigmosphaerostylus itsukaichiensis (Sashida & Tonishi). Kesemua spesies daripada singkapan ini boleh dimasukkan ke dalam Zon Himpunan Pseudoalbaillella lomentaria mewakili usia Sakmarian Awal (Perm Awal). Jujukan ini turut mengandungi beberapa serpihan fosil ammonoid Agathiceras sp.

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KUWAHARA, Kiyoko, and Akira YAO. "Analysis of Radiolarian Fossil Assemblages Using "Model of Steady Faunal Change"." GEOINFORMATICS 15, no. 3 (2004): 151–57. http://dx.doi.org/10.6010/geoinformatics.15.151.

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BOZKURT, ERDIN, BRIAN K. HOLDSWORTH, and ALI KOÇYIGˇIT. "Implications of Jurassic chert identified in the Tokat Complex, northern Turkey." Geological Magazine 134, no. 1 (January 1997): 91–97. http://dx.doi.org/10.1017/s0016756897006419.

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The Tokat Complex is a strongly deformed tectono-sedimentary mixture of low-grade metamorphic rocks with abundant recrystallized limestone and relatively rare serpentinite and radiolarian chert in blocks of variable size. Samples from the radiolarian chert blocks, found in highly crushed zones, each of which corresponds to a thrust sheet within an imbricate thrust zone, have yielded a Tithonian fossil assemblage. They are interpreted as tectonic inclusions emplaced within the Tokat Complex after its main post-early Permian–pre-Liassic metamorphism, and were derived from the rifting and opening of a Neotethyan ocean. The presence of Tithonian blocks within low-grade metamorphic rocks of the Tokat Complex shows that Tethys ocean was in existence in this region by latest Jurassic time. We also suggest that the presence of ophiolitic slices imbricated with the Pontide basement, Tokat Complex, explains the swarm of North Anatolian Fault Zone (NAFZ) splays in this region where the NAFZ likely followed a major pre-existing crustal weakness.

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Wu, Gui-chun, Zhan-sheng Ji, Wei-hua Liao, and Jian-xin Yao. "New biostratigraphic evidence of Late Permian to Late Triassic deposits from Central Tibet and their paleogeographic implications." Lithosphere 11, no. 5 (June 27, 2019): 683–96. http://dx.doi.org/10.1130/l1046.1.

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Abstract Triassic deposits in the Bangong-Nujiang Suture Zone are important for understanding its tectonic nature and evolutionary history, but have not been systematically studied due to a lack of biostratigraphic data. For a long time, the Upper Triassic Quehala Group featuring clasolite has been regarded as the only rocky unit. In recent years, the silicite-dominated Gajia Formation that bears radiolarian fossils was suggested to represent Ladinian to Carnian deposits. The Upper Permian and Lower Triassic rocks have never been excavated and thus are considered to be absent. This research, however, reveals that fossils aged from the Late Permian to Anisian of the Middle Triassic and Norian of the Late Triassic have been preserved in the central Bangong-Nujiang Suture Zone, which provides evidence of Upper Permian to early Middle Triassic deposits and provides new insights on the Upper Triassic strata as well. A new Triassic strata succession is thus proposed for the Bangong-Nujiang Suture Zone, and it demonstrates great similarities with those from Lhasa to the south and Qiangtang to the north. Therefore, we deduce that the Bangong-Nujiang Suture Zone was under a similar depositional setting as its two adjacent terranes, and it was likely a carbonate platform background because limestones were predominant across the Triassic. The newly acquired biostratigraphic data indicate that Lhasa and Qiangtang could not have been located on two separate continents with disparate sedimentary settings; therefore, the Bangong-Nujiang Suture Zone likely did not represent a large ocean between them. This conclusion is supported by lithostratigraphic and paleomagnetic research, which revealed that Lhasa and Qiangtang were positioned at low to middle latitudes during the Early Triassic. Combining this conclusion with fossil evidence, we suggest that the three main Tibetan terranes were in the same palaeobiogeographic division with South China, at least during the Latest Permian to Early Triassic. The Early Triassic conodont species Pachycladina obliqua is probably a fossil sign of middle to low latitudes in palaeogeography.

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Ohba, Hotaka. "Mesozoic radiolarian fossils from Kamishima Island, Mie Prefecture, southwest Japan." Journal of the Geological Society of Japan 103, no. 11 (1997): 1085–88. http://dx.doi.org/10.5575/geosoc.103.1085.

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Kakuwa, Yoshitaka, and James D. Floyd. "Trace fossils in Ordovician radiolarian chert successions in the Southern Uplands, Scotland." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 107, no. 1 (March 2016): 13–22. http://dx.doi.org/10.1017/s1755691017000044.

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ABSTRACTRadiolarian chert and associated siliceous claystone in the Southern Uplands of Scotland are examined, in order to study the Great Ordovician Biodiversification Event of benthic animals on the pelagic ocean bottom. Trace fossils which are uncommon, but convincing, are found in the grey chert and siliceous claystone of Gripps Cleuch. These observations constitute firm evidence that large benthic animals which could leave visible trace fossils had colonised the Iapetan Ocean by the late Middle Ordovician, confirming previous studies from Australia for Panthalassa, the other huge ocean. Red chert is, however, a poor recorder of trace fossils, probably because the highly oxidising environment breaks down organic matter, both inhibiting high-density activity of large benthic animals and removing clear traces of benthic animal life.

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KUWAHARA, Kiyoko, and Akira YAO. "Analysis of origination and extinction of radiolarian fossil assemblages from the Mino Belt." Geoinformatics 11, no. 2 (2000): 90–91. http://dx.doi.org/10.6010/geoinformatics1990.11.2_90.

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Zhang, Kexin, Jichun Huang, Hongfu Yin, Guocan Wang, Yongbiao Wang, Qinglai Feng, and jun Tian. "Application of radiolarians and other fossils in non-Smith strata." Science in China Series D: Earth Sciences 43, no. 4 (August 2000): 364–74. http://dx.doi.org/10.1007/bf02959447.

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Kakuwa, Yoshitaka. "Trace fossils of Ordovician radiolarian chert and siliceous mudstone in Newfoundland, Canada." Sedimentary Geology 358 (August 2017): 176–86. http://dx.doi.org/10.1016/j.sedgeo.2017.07.001.

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Rigby, J. Keith, and James L. Goedert. "Fossil sponges from a localized cold-seep limestone in Oligocene rocks of the Olympic Peninsula, Washington." Journal of Paleontology 70, no. 6 (November 1996): 900–908. http://dx.doi.org/10.1017/s0022336000038580.

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A limited fauna of relatively simple, thin-walled, hexactinellid sponges, including moderately coarse-textured, funnellike Hexactinella(?) conica new species, fine-textured, tubular to branched Hexactinella(?) tubula new species, fragments of delicate Eurete goederti(?) Rigby and Jenkins, 1983, and Farrea(?) species, has been found in the Oligocene Lincoln Creek Formation on Canyon River, in the southcentral part of the Olympic Peninsula, Washington. These sponges dominate a chemosynthetic invertebrate assemblage that included the gastropod Provanna antigua Squires, 1995; the polyplacophoran Leptochiton alveolus (Lovén, 1846), and radiolarians. Most of the sponges are preserved as silica in a localized cherty and botryoidal, calcareous cement-filled limestone formed at bathyal depths by bacterial oxidation of methane at a cold seep. This is the third known report of sponges from ancient chemosynthetic deposits.

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Chang, Shan, Qinglai Feng, and Lei Zhang. "New Siliceous Microfossils from the Terreneuvian Yanjiahe Formation, South China: The Possible Earliest Radiolarian Fossil Record." Journal of Earth Science 29, no. 4 (August 2018): 912–19. http://dx.doi.org/10.1007/s12583-017-0960-0.

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Kawatani, Ayako, Katsuo Sashida, Sachiko Agematsu, and Naoki Kohno. "Radiolarian fossils from the Miocene Tsurushi Formation distributed in Sado Island, Niigata Prefecture, Japan." BULLETIN OF THE GEOLOGICAL SURVEY OF JAPAN 70, no. 1-2 (March 29, 2019): 91–99. http://dx.doi.org/10.9795/bullgsj.70.91.

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Parkhaev, P. Yu, Yu E. Demidenko, and M. A. Kulsha. "The Problematic Fossil Mobergella radiolata as an Index Species of the Lower Cambrian Stages." Stratigraphy and Geological Correlation 28, no. 2 (March 2020): 135–56. http://dx.doi.org/10.1134/s0869593820020057.

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Dzulkafli, Muhammad Ashahadi, Basir Jasin, Mohd Shafeea Leman, and Norasiah Sulaiman. "Fosil Radiolaria daripada Batuan Bersilika-Rijang di Pos Blau (Singkapan PB-1), Baratdaya Kelantan, Semenanjung Malaysia." Sains Malaysiana 47, no. 10 (October 31, 2018): 2259–68. http://dx.doi.org/10.17576/jsm-2018-4710-03.

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Haggart, James W., J. Brian Mahoney, Michelle Forgette, Elizabeth S. Carter, Claudia J. Schröder-Adams, Catherine I. MacLaurin, and Arthur R. Sweet. "Paleoenvironmental and chronological constraints on the Mount Tatlow succession, British Columbia: first recognition of radiolarian and foraminiferal faunas in the Intermontane Cretaceous back-arc basins of western Canada1This article is one of a series of papers published in this Special Issue on the theme of New insights in Cordilleran Intermontane geoscience: reducing exploration risk in the mountain pine beetle-affected area, British Columbia.2Geological Survey of Canada Contribution 20100279." Canadian Journal of Earth Sciences 48, no. 6 (June 2011): 952–72. http://dx.doi.org/10.1139/e11-019.

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The Cretaceous succession at Mount Tatlow, British Columbia, is a cornerstone of Cordilleran stratigraphy, preserving a mostly continuous record of upper Lower Cretaceous to lower Upper Cretaceous sedimentary strata. The succession is capped by volcanic strata of the Powell Creek formation. Lithofacies assemblages within the Mount Tatlow succession reflect sedimentation in a deep-water submarine fan system at the base of the section, to overlying submarine-fan and to pro-deltaic deposition, and, finally, to delta-plain sedimentation at the top of the succession. Radiolarian and foraminifer fossils from the lower part of the Mount Tatlow section are the first recovered from the Intermontane basins of British Columbia and indicate a middle Albian to Cenomanian age, most likely Cenomanian. The presence of these fossils indicates that open-marine conditions existed locally in the basin at this time, but the strongly altered and pyritized nature of the fauna suggests that a reducing environment fostered early diagenetic pyritization processes in the subsurface sediments. Detrital zircon populations collected from the succession are in agreement with the paleontological ages.

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41

MATSUOKA, Atsushi, and Tatsuo OJI. "Middle Jurassic radiolarian fossils from the Magisawa Formation in the Taro Belt, North Kitakami Mountains." Journal of the Geological Society of Japan 96, no. 3 (1990): 239–41. http://dx.doi.org/10.5575/geosoc.96.239.

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42

Kazuka, Takuro, Tanio Ito, and Yoshiaki Aita. "Eocene Radiolarian fossils from the Sarugawa Formation, the Hidaka foreland fold-and-thrust belt, Hokkaido, Japan." Journal of the Geological Society of Japan 108, no. 7 (2002): 474–77. http://dx.doi.org/10.5575/geosoc.108.474.

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43

Saito, Makoto, Yoji Teraoka, Kazuhiro Miyazaki, and Seiichi Toshimitsu. "Radiolarian fossils from the Nishikawauchi Formation in the Onogawa Basin, east Kyushu, and their geological significance." Journal of the Geological Society of Japan 99, no. 6 (1993): 479–82. http://dx.doi.org/10.5575/geosoc.99.479.

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44

Ueda, Hayato, Makoto Kawamura, and Keiji Iwata. "Occurrence of the Paleocene radiolarian fossils from the Idon'nappu Belt, central part of Hokkaido, Northern Japan." Journal of the Geological Society of Japan 99, no. 7 (1993): 565–68. http://dx.doi.org/10.5575/geosoc.99.565.

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Zyabrev, S. V., and V. I. Anoikin. "New age data on the deposits of the Kiselevka-Manoma accretionary complex based on radiolarian fossils." Russian Journal of Pacific Geology 7, no. 3 (May 2013): 217–25. http://dx.doi.org/10.1134/s1819714013030081.

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TAKAHASHI, Osamu, Naoko HAYASHI, and Atsushi ISHII. "Radiolarian fossils from the Masutomi Group, southwestern part of the Kanto Mountains, central Japan, and their significance." Journal of the Geological Society of Japan 95, no. 12 (1989): 953–55. http://dx.doi.org/10.5575/geosoc.95.953.

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Saito, Makoto, and Hitoshi Tsukamoto. "Chert breccia, its occurrence and radiolarian fossils in the Hichiso-Mugi area, central Mino Terrane, central Japan." Journal of the Geological Society of Japan 99, no. 2 (1993): 117–33. http://dx.doi.org/10.5575/geosoc.99.117.

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Ueda, Hayato, Miwako Mori, and Izumi Sato. "Early Jurassic radiolarian fossils from mudstone within an accretionary complex south of Hirosaki City, Aomori Prefecture, Japan." Journal of the Geological Society of Japan 115, no. 11 (2009): 610–13. http://dx.doi.org/10.5575/geosoc.115.610.

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Uchino, Takayuki, and Rie S. Hori. "Early Jurassic radiolarian fossils from mudstone of the Ashio Terrane in the Kambara Mountains, Niigata Prefecture, Japan." Journal of the Geological Society of Japan 116, no. 8 (2010): 441–46. http://dx.doi.org/10.5575/geosoc.116.441.

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Kamikuri, Shin-ichi. "Evolutionary changes in the biometry of the fossil radiolarian Stichocorys peregrina lineage in the eastern equatorial and eastern North Pacific." Marine Micropaleontology 90-91 (June 2012): 13–28. http://dx.doi.org/10.1016/j.marmicro.2012.04.003.

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