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Reproducibility of 41 Unitary Associations from the investigated localities (output of UA-Graph program v. 0.27, Hammer et al., November 2008), with correlation to radiolarian zones and chronostratigraphic units. Black squares indicate Unitary Associations identified in a region or section. Grey squares indicate unions of Unitary Associations which are not individually reproducible. Several sections in one region were merged in a local zonation, if studied by one author (see chapter 3.3.) and are represented by a single column. Radiolarian inventory of all samples and the final dataset composed of local zonations are given in the electronic supplementary material (Appendices C and D respectively).
Source publication
Jurassic radiolarians from 220 samples in Queen Charlotte Islands, B.C., Williston Lake, B.C., east-central Oregon, Baja California Sur, southern Spain, Austria, Slovenia, Turkey, Oman, Japan and Argentina were studied in order to construct global zonation for the Pliensbachian, Toarcian and Aalenian stages. Well-preserved faunas from continuous st...
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Citations
... The Early Jurassic assemblage found in Sample 85-36-1 is of greatest interest, because no similar representative assemblages of this age were known within The Crucella miho is known from the Pliensbachian of Turkey (De Wever, 1981) and British Columbia (Carter et al., 1988(Carter et al., , 2010, Lower Jurassic of Argentina (Pujana, 1996), and Hettangian-Sinemurian of Peru (Suzuki et al., 2002). The Hagiastrum rudimentum occurs in the upper Sinemurian and lower Pliensbachian of British Columbia (Carter et al., 1998), Pliensbachian of Mexico (Whalen and Carter, 2002), and Hettangian-Sinemurian of Peru (Suzuki et al., 2002). ...
... The Katroma regina is known from Sinemurian of British Columbia (Carter et al., 1998). The Lantus praeobesus occurs in the Sinemurian and Pliensbachian of British Columbia (Goričan et al., 2006;Carter et al., 2010) and Hettangian-Pliensbachian of Japan (Hori, 1990). The Parahsuum edenshawi is known in the Pliensbachian of British Columbia (Carter et al., 1988), Austria (O'Dogherty and Gawlick, 2008), and Greece (Chiari et al., 2013), whereas P. simplum occurs from the Hettangian to Toarcian, in particular, in the Sinemurian-Pliensbachian of British Columbia (Carter et al., 1998(Carter et al., , 2010, Pliensbachian of Austria (O'Dogherty and Gawlick, 2008), Greece (Chiari et al., 2013), and Mexico (Whalen and Carter, 2002), Hettangian of Bavaria (Kozur and Mostler, 1990), and Hettangian-Toarcian of Japan (Hori, 1988). ...
... The Lantus praeobesus occurs in the Sinemurian and Pliensbachian of British Columbia (Goričan et al., 2006;Carter et al., 2010) and Hettangian-Pliensbachian of Japan (Hori, 1990). The Parahsuum edenshawi is known in the Pliensbachian of British Columbia (Carter et al., 1988), Austria (O'Dogherty and Gawlick, 2008), and Greece (Chiari et al., 2013), whereas P. simplum occurs from the Hettangian to Toarcian, in particular, in the Sinemurian-Pliensbachian of British Columbia (Carter et al., 1998(Carter et al., , 2010, Pliensbachian of Austria (O'Dogherty and Gawlick, 2008), Greece (Chiari et al., 2013), and Mexico (Whalen and Carter, 2002), Hettangian of Bavaria (Kozur and Mostler, 1990), and Hettangian-Toarcian of Japan (Hori, 1988). ...
The assemblages of the Early Jurassic (Hettangian-Pliensbachian) and Late Jurassic-Early Cre-taceous (Tithonian-Berriasian) radiolarians were described for the first time in the eastern part of the Ekonai Zone of the Koryak Highland. The Hettangian-Pliensbachian assemblage was found in siliceous rocks of the Ionai Nappe and this finding expands the stratigraphic interval of its siliceous sequences from the Carbonif-erous to the Early Jurassic. The Tithonian-Berriasian assemblage was found in volcanosiliceous rocks of the Yanranai accretionary complex. Both assemblages contain taxa abundant in the Tethyan regions.
... Талякаурхын (рис. 2, пункты 8, 9) с Laxtorum jurassicum [6] благодаря обилию губчатых форм и примитивно скульптурированных Praeparvicingula elementaria (Carter) [37,38], а также многочисленных парахзуумов [5], имеет суббореальные черты. Суббореальный ранне-среднебайосский комплекс с Pantanellium foveatum-Bagotum maudense из океанических кремней (бассейна р. ...
... Койвэрэлан) с обилием губчатых представителей рода Bagotum благодаря присутствию Pantanellium и многочисленных Eoxitus hungaricus Kozur указывают на тепловодную среду и приближенность к субэкваториальной области. Указанный комплекс радиолярий начала средней юры сходен с одновозрастными суббореальными радиоляриевыми ассоциациями Японии и Северной Америки [36,37]. Другое положение занимали в позднем байоссе кремнисто-вуканогенные толщи океанического ложа (рис. ...
Jurassic–Cretaceous siliceous–volcanogenic rocks from nappes of tectonostratigraphic sequences of the East Asia Middle Cretaceous Okhotsk–Koryak orogenic belt are represented by a wide range of geodynamic sedimentation settings: oceanic (near-spreading zones, seamounts, and deep-water basins), marginal seas, and island arcs. The taxonomic compositions of radiolarian communities are used as paleolatitude indicators in the Northern Pacific. In addition, a tendency toward climate change in the Mesozoic is revealed based on these communities: from the warm Triassic to the cold Jurassic with intense warming from the Late Jurassic to the Early Cretaceous. Cretaceous warming led to heating of ocean waters even at moderately high latitudes and to the development of Tethyan radiolarians there. These data are confirmed by a global Cretaceous temperature peak coinciding with a high-activity pulse of the planetary mantle superplume system, which created thermal anomalies and the greenhouse effect. In addition, the Pacific superplume attributed to this system caused accelerated movement of oceanic plates, which resulted in a compression setting on the periphery of the Pacific and the formation of the Okhotsk–Koryak orogenic belt on its northwestern framing in the Middle Cretaceous, where Mesozoic rocks of different geodynamic and latitudinal–climate settings were juxtaposed into allochthonous units.
... Studied Early and Middle Jurassic assemblages display clear Tethyan affinity and therefore we can determine many taxa with good stratigraphic potential (Table 1). It allows us to trace Tethyan biostratones proposed for this stratigraphic interval (Baumgartner et al., 1995b;Carter et al., 2010) (Table 2). ...
... It is worth of note that the Aalenian Stage is subdivided only into two parts in the zonation of Carter et al. (2010) despite common subdivision of the Aalenian into three substages (Gradstein et al., 2012). In the present paper we follow the subdivision of Aalenian after Gradstein et al. (2012). ...
... Sample 86-11-16. Hsuum exiguum Yeh and Cheng (Plate 1, fig. 1) has stratigraphic range from unitary associations (UA) 29 to 36 (Carter et al., 2010) which is equal to the interval from the middle-late Toarcian (Elodium pessagnoi -Hexasaturnalis hexagonus Zone) to the early-middle Aalenian (Higumastra transversa -Napora nipponica Zone) (Carter et al., 2010). ...
Lower and Middle Jurassic Radiolaria from cherts of the
Kiselevka-Manoma accretionary complex (lower flow of Amur
River, eastern Russia)
Nikita Yu. BRAGIN
Geological Institute of Russian Academy of Sciences, Pyzhevsky 7, Moscow,
& Liubov G. BRAGINA
119017, Russia. bragin.n@mail.ru; l.g.bragina@mail.ru
The Kiselevka-Manoma Complex is represented by Jurassic – Early Cretaceous cherts,
basic volcanics and limestones. It is the youngest accretionary complex of Sikhote-Alyn
accretionary system. It forms long, narrow and discontinuous band along lower flow of Amur
River, and it is located directly east from Amur Terrane composed of Lower Cretaceous
clastics (Khanchuk et al., 1994; Zyabrev, 1994, 1996; Zyabrev et al., 2005). Kiselevka-
Manoma Complex was repeatedly studied during long time interval. Units of this complex
exposed in type locality near Kiselevka Village were dated by ammonoids and bivalvs from
limestones as Lower Jurassic (most possibly Hettangian to Sinemurian) (Zhamoida, 1972),
and as Upper Triassic – Lower Jurassic by radiolarians studied from cherts in thin sections
(Zhamoida, 1972). Later studies substantionally changed and detalized the stratigraphy of the
Kiselevka-Manoma Complex. According to Zyabrev (1996) and Zyabrev & Anoikin (2013),
this complex consists of:
1. Basic volcanics and Liassic limestones in tectonic contact.
2. Cherts, mostly red, sometimes interbedded with cherty mudstones, with
radiolarian assemblages ranging from Lower Jurassic to Lower Cretaceous
(Hauterivian).
3. Olive-grey cherty mudstones, replaced upsection by dark-grey mudstones,
with radiolarians of Lower Cretaceous (Barremian – middle Aptian)
4. Clastic turbidites.
Cretaceous Radiolaria were illustrated by Zyabrev, but Jurassic ones still remained not
illustrated and even not studied, so that we have no exact knowledge of their age/composition
as well as of detailed stratigraphy of Jurassic part of the Kiselevka-Manoma Complex. The
aim of this work is to give first results on the Lower to Middle (Toarcian – Bajocian) Jurassic
radiolarians. We studied the chert units on the left bank of Amur River west from Izvestkovyi
Bay. Cherts exposed here are deformed into large synform complicated by thrusts and shear
zones. Cherts are characterized by abundant radiolarians that allow to reconstruct the part of
stratigraphic section starting from lower part:
Unit 1. Red to brownish-red clayey cherts intercalated with brownish-red cherty
mudstones with Pliensbachian to lower Toarcian Radiolaria: Canoptum sp. cf. C. anulatum
Pessagno & Poisson, Crucella sp., Hsuum sp. cf. H. exiguum Yeh & Cheng, Katroma clara
Yeh, Katroma sp. cf. K. ninstintsi Carter, Lantus sp. cf. L. obesus (Yeh), Parahsuum ovale
Hori & Yao, Paronaella sp. cf. P. corpulenta De Wever, Paronaella sp. cf. P. curticrassa
Carter & Dumitrica, Pleesus sp. cf. P. aptus Yeh. Upper part of unit is characterized by
Bistarkum sp. cf. B. rigidium Yeh, Citriduma sp. cf. C. hexaptera (Conti & Marcucci) and
Parahsuum sp. aff. P. edenshawi (Carter). Thickness is 20-25 m.
2. Red ribbon cherts with rare intercalations of grey cherts and red cherty mudstones
with the following radiolarian assemblages:
Middle Toarcian to lower Aalenian with Crucella sp. cf. C. angulosa (s.l.) Carter,
Hsuum exiguum Yeh & Cheng, Hsuum sp. aff. H. exiguum Yeh & Cheng, Hsuum sp. cf. H.
lucidum Yeh, Parasaturnalis sp. cf. P. yehae Dumitrica & Hori and Paronaella grahamensis
Carter;
Proceedings of 14th INTERRAD, March 22-26 2015, Antalya, Turkey
Session 3- Radiolarians in Geodynamics (Poster Session)
118
Lower Aalenian to lower-middle Bajocian with Hsuum matsuokai Isozaki & Matsuda,
Linaresia sp., Parahsuum ? sp. cf. P. hiconocosta Baumgartner & De Wever, Parahsuum ?
grande Hori & Yao, Parahsuum sp. cf. P. longiconicum Sashida and Parasaturnalis
diplocyclis (Yao);
Upper Aalenian to upper Bajocian with Hexasaturnalis hexagonus (Yao), Parahsuum ?
hiconocosta Baumgartner & De Wever, P. ? sp. cf. P. natorense (El Kadiri), P. ? sp. cf. P.
magnum Takemura and Tetraditryma sp. cf. T. praeplena Baumgartner;
Lower to middle Bajocian with Dictyomitrella (?) sp. aff. D. kamoensis Mizutani &
Kido, Emiluvia splendida Carter, Sella benilderkoulensis (El Kadiri), Sella chrafatensis (El
Kadiri), Mirifusus proavus Tonielli, Palinandromeda sp. cf. P. sognoensis Baumgartner,
Parahsuum sp. aff. P. izeense (Pessagno & Whalen), P. sp. cf. P. izeense (Pessagno &
Whalen), Transhsuum maxwelli (Pessagno), T. hisuikyoense (Isozaki & Matsuda) and
Tritrabs simplex Kito & De Wever. Thickness is 40-50 m.
These chert units are in tectonical contact with clastic turbidites in the west and are
limited by shear zone in the east, furthermore chert blocks in this shear zone have Early
Cretaceous age. Therefore we examined only fragment of Jurassic section and we still don’t
know the oldest age of the section as well as the composition of Upper Jurassic radiolarian
assemblages. At last the examined Lower and Middle Jurassic assemblages display clear
Tethyan affinity and they were analyzed utilizing the biozonations of Baumgartner et al.
(1995) and Carter et al. (2010).
References
Baumgartner, P.O., Bartolini A., Carter E.S. & others, 1995. Middle Jurassic to Early
Cretaceous radiolarian biochronology of Tethys based on unitary associations. Mem.
Geol. Lausanne. 23, 1013-1048.
Carter, E.S., Goriиan, Љ., Guex J. & others, 2010. Global radiolarian zonation for the
Pliensbachian, Toarcian and Aalenian. Palaeogeography, Palaeoclimatology,
Palaeoecology 297, 401-419.
Khanchuk, A.I., Ognyanov, N.V., Popova, I.M. & Filippov, A.N., 1994. New data on the Early
Cretaceous deposits of the Lower Amur region. Dokl. Ross. Akad. Nauk 338, 5, 666–
671.
Zhamoida, A.I., 1972. Biostratigraphy of the Mesozoic chert units of the East of USSR (on
the base of radiolarian study). Ministry of geology USSR. Trans. All Union Geological
Scientific Research Institute (VSEGEI), N.S. 183, 1-238.
Zyabrev, S.V., 1994. Early Cretaceous cherts of the Kiselevka–Manoma terrane—the
youngest oceanic deposits in the structure of southern continental part of Russian Far
East // Tikhookeanskaya Geologiya 6, 74–82.
Zyabrev, S.V., 1996. Cretaceous radiolarian fauna from the Kiselyovsky subterrane, the
youngest accretionary complex of the Russian continental far east: Paleotectonic and
paleogeographic implications. The Island Arc 5, 140-155.
Zyabrev, S.V. & Anoikin V.I., 2013. New age data on the deposits of the Kiselevka–Manoma
accretionary complex based on radiolarian fossils. Russian Journal of Pacific Geology 7
3, 217–225.
Zyabrev, S.V., Martynyuk, M.V. & Shevelev, E.K., 2005. Southwestern fragment of the
Kiselevka–Manoma accretionary complex, Sikhote-Alin: stratigraphy, subduction
accretion, and post-accretionary displacements. Tikhookeanskaya Geologiya 24 1, 45–
58.
Key words: Radiolaria, Lower Jurassic, Middle Jurassic, accretionary complex, eastern
Russia.
... The Pliensbachian/Toarcian boundary is correlated with the interval between bed number 1560 and 1580 in the Katsuyama section based on the uppermost part of P. simplum IV Subzone of Hori (1990Hori ( , 1997) (Trillus elkhornensis Assemblage zone) and the lower part of the H. hexagonus (Hh) Zone (Hori, 1990(Hori, , 1997Gröcke et al., 2010). These radiolarian zones equate to the radiolarian zones in Carter et al. (2010) of Eucyrtidiellum nagaiae-Praeparvicingula tlellensis to Elodium pessagnoi-H. hexagonus. ...
... hexagonus. The ages of these radiolarian zones were constrained as upper Pliensbachian and lower Toarcian, respec-tively, by ammonite biostratigraphy of Queen Charlotte Islands and other areas from North America (Carter et al., 2010). Thus, the uppermost part of the P. simplum IV Subzone of Hori (1990Hori ( , 1997 is equivalent to the Emaciaticeras emaciatum/Dactylioceras tenuicostatum ammonite Zone boundary of Europe, where the Pliensbachian/Toarcian boundary was assigned as 182.7 ± 0.5 Ma (Ogg and Hinnov, 2012). ...
... Its efficiency in resolving complicated biochronological problems has been demonstrated with taxonomic groups that are differing in the completeness of their fossil record (e.g. ammonites , brachiopods, mammals, nannoplankton or radiolarians ; Angiolini & Bucher 1999; Boulard 1993; Baumgartner et al. 1995; Guex & Martinez 1996; Monnet & Bucher 2002, 2007; Baumgartner 2006; Brühwiler et al. 2010; Carter et al. 2010). It usually leads to a significant improvement of biochronological resolution, even in the case of ammonites (e.g. ...
Monnet, C., Klug, C., Goudemand, N., De Baets, K. & Bucher, H. 2011: Quantitative biochronology of Devonian ammonoids from Morocco and proposals for a refined unitary association method. Lethaia, Vol. 44, pp. 469–489.
Based on a rich dataset, the biostratigraphy of the late Emsian and the Eifelian (Early–Middle Devonian) ammonoids from the Moroccan Tafilalt is re-evaluated. We processed this dataset (comprising 53 species from 15 sections) with the unitary association method (UAM), by means of the UA-graph freeware. This led to the construction of a sequence of 17 UAs (maximal sets of actually or virtually coexisting taxa), which are grouped into 10 laterally reproducible association zones. This biostratigraphical subdivision of this interval is in some parts finer than the classically used empirical stratigraphical scheme and than a previous graphic correlation analysis. It enabled us to measure regional ammonoid diversity of this interval in detail. The UAM is a powerful biochronological method, which benefits from complementary tools to analyse conflicting inter-taxon stratigraphical relationships inherent to complex biostratigraphical datasets. In cases of under-constrained superpositional relationships between the taxa, the UAM can yield results, which are not parsimonious in terms of reconstructed virtual coexistences. We suggest several additions to complement the algorithmic steps of the method. The most important is the exhaustive or heuristic reconstruction of possible solutions resolving the observed biostratigraphical contradictions (conflicting inter-taxon superpositional relationships and cycles between maximal cliques) and the selection among the solutions of the most-parsimonious one(s) in terms of reconstructed virtual coexistences. Multiple equivalent results may then be processed with standard consensus techniques. Finally, the robustness of the results can be tested by bootstrapping methods to provide confidence estimates on the ranges and associations of studied taxa. □Ammonites, Anti-Atlas, biostratigraphy, correlation, zonation, diversity.
Lithostratigraphy and radiolarian biostratigraphy in the Halashi
01 section of the Kermanshah area, west Iran
Mahin RAMI
& Mahmoud Reza MAJIDIFARD3
1, Seyed Hamid VAZIRI1, Atsushi MATSUOKA2
1) Department of Geology, North-Tehran Branch, Islamic Azad University,
Tehran, Iran. m_rami1385@yahoo.com; h_vaziri@iau-tnb.ac.ir
2) Department of Geology, University of Niigata, Japan.
matsuoka@geo.sc.niigata-u.ac.jp
3) Research Institute for Earth Sciences, Geological Survey and Mineral
Explorations. m_majidifard@yahoo.com
In order to study the biostratigraphy and paleoecology of Mesozoic deposits in the range
of the Kermanshah (Kermanshah Province) region, a stratigraphic section (the Halashi 01) in
the west Kermanshah area was selected. The section consists mainly of chert, siliceous
mudstone, marlstone, limestone and mudstone. A total of 143 rock samples were collected
from the Halashi 01 section. Identified taxa include 57 genera and 165 species from this
section; 50 genera and 155 species of radiolarians, 4 genera and 6 species of sponges, 2
genera and 3 species of planktonic foraminifera, and 1 genus and 1 species of benthic
foraminifera. These fossil records indicate that the study section is Tithonian (Late Jurassic)
to early Valanginian (Early Cretaceous) in age.
High diversity and abundant occurrence of radiolarians in the study section indicate that
a favorable condition was prevailed during the deposition of the strata in Tithonian to early
Valanginian time. Nassellarians are generally more abundant than spumellarians, which may
suggest the sediments were accumulated in a great depth.
Key words: Radiolarian, biostratigraphy, Iran, Tithonian, early Valanginian, Late Jurassic,
Early Cretaceous.
The study of the radiolarian ribbon chert is a key in determining the origins of associated Mesozoic oceanic terranes and may help to achieve a general agreement regarding the basic principles on the evolution of the Caribbean Plate. The Bermeja Complex of Puerto Rico, which contains serpentinized peridotite, altered basalt, amphibolite, and chert (Mariquita Chert Formation), is one of these crucial oceanic terranes. The radiolarian biochronology presented in this work is mainly based by correlation on the biozonations of Baumgartner et al. (1995) and O’Dogherty (1994) and indicates an early Middle Jurassic to early Late Cretaceous (late Bajocian–early Callovian to late early Albian–early middle Cenomanian) age. The illustrated assemblages contain about 120 species, of which one is new (Pantanellium karinae), and belonging to about 50 genera. A review of the previous radiolarian published works on the Mariquita Chert Formation and the results of this study suggest that this formation ranges in age from Middle Jurassic to early Late Cretaceous (late Aalenian to early–middle Cenomanian) and also reveal a possible feature of the Bermeja Complex, which is the younging of radiolarian cherts from north to south, evoking a polarity of accretion. On the basis of a currently exhaustive inventory of the radiolarite facies s.s. on the Caribbean Plate, a re-examination of the regional distribution of Middle Jurassic sediments associated with oceanic crust, and a paleoceanographic argumentation on the water currents, we come to the conclusion that the radiolarite and associated Mesozoic oceanic terranes of the Caribbean Plate are of Pacific origin. Eventually, a discussion on the origin of the cherts of the Mariquita Formation illustrated by Middle Jurassic to middle Cretaceous geodynamic models of the Pacific and Caribbean realms bring up the possibility that the rocks of the Bermeja Complex are remnants of two different oceans.
Oceanic anoxic events were time intervals in the Mesozoic characterized by widespread distribution of marine organic matter-rich sediments (black shales) and significant perturbations in the global carbon cycle. These perturbations are globally recorded in sediments as carbon isotope excur- sions irrespective of lithology and depositional environment. During the early Toarcian, black shales were deposited on the epi- and pericontinental shelves of Pangaea, and these sedi- mentary rocks are associated with a pronounced (ca. 7 ‰) negative (organic) carbon isotope excursion (CIE) which is thought to be the result of a major perturbation in the global carbon cycle. For this reason, the lower Toarcian is thought to represent an oceanic anoxic event (the T-OAE). If the T- OAE was indeed a global event, an isotopic expression of this event should be found beyond the epi- and pericontinen- tal Pangaean localities. To address this issue, the carbon iso- tope composition of organic matter (δ13Corg) of lower Toar- cian organic matter-rich cherts from Japan, deposited in the open Panthalassa Ocean, was analysed. The results show the presence of a major (>6‰) negative excursion in δ13Corg that, based on radiolarian biostratigraphy, is a correlative of the lower Toarcian negative CIE known from Pangaean epi- and pericontinental strata. A smaller negative excursion in δ13Corg (ca. 2 ‰) is recognized lower in the studied succes- sion. This excursion may, within the current biostratigraphic resolution, represent the excursion recorded in European epi- continental successions close to the Pliensbachian/Toarcian boundary. These results from the open ocean realm sug- gest, in conjunction with other previously published datasets, that these Early Jurassic carbon cycle perturbations affected the active global reservoirs of the exchangeable carbon cycle (deep marine, shallow marine, atmospheric).
