Middle to Late Cretaceous radiolarian zonation of the Bering region, U.S.S.R.

139

Marine Micropaleontology, 11 (1986): 139--149 Elsevier Science Publishers B.V., Amsterdam -- Printed in The Netherlands

MIDDLE TO LATE CRETACEOUS RADIOLARIAN ZONATION OF THE BERING REGION, U.S.S.R.

VALENTINA S. VISHNEVSKAYA

Institute of the Lithosphere of the U.S.S.R. Academy of Sciences, Moscow (U.S.S.R.) (Received January 15, 1985; accepted August 15, 1985)

Abstract Vishnevskaya, V.S., 1986. Middle to Late Cretaceous radiolarian zonation of the Bering regmn, U.S.S.R. Mar. Micropaleontol., 11: 189--149. The Middle--Upper Cretaceous volcanogenic-siliceous geological sections of the Koryak highland, the submerged Shirshov Ridge, and northern, central and eastern Kamchatka are investigated micropaleontologically. Radiolarians were extracted from siliceous rocks by means of HF. Their preservation is satisfactory. As a result of biostratigraphical research, six radiolarian assemblages are distinguished. The oldest is the Albian--Turonian assemblage with Pseudodictyomitra pseudomacrocephala. The age of this complex is controlled by planktonic foraminifers co-occurring with radiolarians. The following is the Coniacian--Early Santonian assemblage with Archaeospongoprunum bipartitum, which is accompanied by Early Santonian planktonic foraminifers. The Late Santonian--Early Campanian age of the assemblage with Pseudoaulophacus floresensis is confirmed by macrofossils. A Middle--Late Campanian age of the Amphipyndax enesseffi assemblage is proved by the widespread Inoceramus schmidti. A Late Campanian--Early Maastrichtian age of the radiolarian assemblage with Clathrocyclas diceros is in good agreement with diatoms and silicoflagellates. A Late Maastrichtian--Danian age of the assemblage with Bothryopyramis sanjoaquinensis is proved by foraminifers. These radiolarian assemblages can be considered as zonal for the boreal area of the northeast of the U.S.S.R. and as a key for further biostratigraphic research.

Introduction

and especially the radiolarians, play important role in biostratigraphy.

The Bering region is situated in the northeast of the U.S.S.R. in the transitional zone between the Euroasian continent and the Pacific Ocean (Fig. 1). It includes the AnadyrKoryak structures in the northwest, the Olutor--Kamchatka structures in the south and submerged structures of the marginal Bering Sea in the east. All Late Cretaceous formations, including the siliceous-volcanogenic sequences studied are tectonized and form a complicated system of nappes. Because of the complicated geological structure of the Cretaceous formations, as well as the lithographic resemblance of the siliceous-volcanogenic rocks, the microfossils, 0377-8398/86/$03.50

an

Previous Investigations Cretaceous radiolarians of the northeast of the U.S.S.R. have been studied by many scientists. Lipman (1952) was the first to distinguish a Late Cretaceous assemblage with Dictyomitra in rocks later to be called the Vatynsky complex, referring to the homonym river in the Koryak highland. Zhamoida (1972) biostratigraphically subdivided all the siliceous sequences of the Far East of the U.S.S.R. by means of radiolarians. He suggested that three consecutive radiolarian assemblages should be dis-

© 1986 Elsevier Science Publishers B.V.

140

BERING SEA

56

?

~O

o

fP

Fig. 1. Map showing the location of assemblages found in the Bering region. Assemblage with: 1 = Dictyomitra pseudomacrocephala; 2 ffi Archaeospongoprunum bipartitum; 3 = Pseudoauiophacus florensis; 4 = Amphipyndax enesseffi; 5 ffi Chlathrocyclas diceros; 6 ffi Bathropyramis sanjoaquinensis.

tinguished in the Late Cretaceous of the Koryak highland, namely: the Vatynsky (Cenomanian--Campanian or Santonian-Campanian), the Inetyvayamsky (Maastrichtian-Danian) and the Votchvinaky (Danian), previously described by R. Lipman (Zhamoida, 1972). Later on, Kasinzova (1979} repeatedly studied the Cretaceous Radiolaria of the Koryak highland and differentiated two new radiolarian assemblages in the Pengin (Albian-Coniacian} and Mametchin (Albian-Cenomanian) suites. She continued to describe the Inetyvayamsky radiolarian assemblage (Maastrichtian--Danian) and redescribed the Vatynian radiolarian as the Ilpinsky, narrowing down the age of the Vatynian assemblage to the Campanian. Such a conclusion has many contradictions, which resulted in discussions. Earlier workers studied radiolarian skeletal remnants of the Far East of the U.S.S.R. traditionally, in sections. Since the probability of accurate diagnostics of Mesozoic radiolarian species in thin sections is very low, a discrepancy in age determinations of volcanogenic-sfliceous sequences often

PLATE I 1. Archaedictyomitra squinaboli, x 250, Coniacian--Early Campanian. 2. Sethocyrtis ambiguus sp. nov., x 350, Coniacian--Early Santonian. 3. Amphipyndax stocki var. A, X 340, Coniacian--Early Santonian. 4. Pseudoaulophacus florcnsensis, x 300, Late Santonian--Early Campanian. 5. Dictyomitra densicastata, X 250, Late Santonian--Early Campanian. 6. Dictyomitra striata, X 150, Middle--Late Campanian. 7. Dictyomitra andersoni, × 250, Late Campanian--Early Maastrichtian.

PLATE II (see p. 142) 1,3. A m p h i p y n d a x stocki vat. A.I: × 175, 3: x 260, Campanian. 2,4. A m p h i p y n d a x stocki vat. B, 2: X 150, 4: × 230, Campanian. 5. Amphipyndax stocki vat. C, × 230, Late Campanian--Danian. 6. Stichomitra alamedaensis, × 380, Late Campanian--Early Maastrichtian.

PLATE III (see p. 143) 1. Spongurus mollis sp. nov., x 350, Late Maastrichtian--Danian. 2. Clathrocyclas gravis sp. nov., x 350, Late Carnpanian--Early Maastrichtian. 3. Theocampe altamontensis, x 315, Late Maastrichtian--Danian. 4. Bathropyramis sanjoaquinensis, × 455. Late Maastrichtian--Danian. 5. Cornutella californica var. B, X 250, Campanian--Early Maastrichtian. 6. Cornutella californica vat. A, x 250, Late Maastrichtian--Danian.

141

PLATE I

142

PLATE II

(for explanation see p. 140)

143

PLATE III

(for explanation see p. 140)

144

TABLE I Cretaceous radiolarian assemblages of the Bering region of the U.S.S.R. Species

Acaeniotyle umbilicata (Rust) Alievium helenae Schaaf Excentropylomma cenomana Dumitrica Pseudodictyomitra pseudomacrocephala Squinabol Pseudodictyomitra pentacolensis Pessagno Thanarla veneta (Squinabol) Thanarla elegantissima (Cita) Holocryptocapsa hindei Tan Sin Hok Holocryptocanium barbui Dimitrica Holocryptocanium astiensis Pessagno Pseudoaulophacus praefloresensis Pessagno Patellula planoconvexa (Pessagno) Amphibrachium cf. concentricum Lipman Archaeospongoprunum bipartitum Pessagno Archaeospongoprunum aff. vascoensis Pessagno Orbiculiforma monticelloensis Pessagno Orbiculiforma cf. vacaensis Pessagno Dictyomitra napaensis Pessagno Dictyomitra ? duodecimcostata (Squinabol) Neosciadiacapsa jencinsi Pessagno Cyrtocalpis crassitestata Rust Amphipyndax stocki (Campbell and Clark) var..~ Vish. Sethocyrtis ambiguus sp. nov. Orbiculiforma quadrata Pessagno Cromyodruppa concentrica Lipman Amphibrachium ex gr. ornatum Lipman Archaeodictyomitra squinaboli Pessagno Archaeodictyomitra lamellicostata Foreman Theocapsomma aft. amphora Campbell and Clark Pseudoaulophacus lenticulatus (White) Pseudoaulophacus floresensis Pessagno Pseudoaulophacus colburni Pessagno Amphibrachium spongiosum Lipman Phaseliforma subcarinata Pessagno Phaseliforma meganosensis Pessagno Orbiculiforma campbellensis Pessagno Orbiculiforma sacramentoensis Pessagno Prunobrachium kennetti Pessagno Prunobrachium longum Pessagno Prunobrachium aucklandensis Pessagno Prunobrachium crassum (Lipman) Prunobrachium ex. gr. sibericum (Lipman) Alievium myrphyi Pessagno Dictyomitra koslovae Foreman Dictyomitra densicostata Pessagno Dictyomitra striata Lipman Dictyomitra torquata Foreman Amphipyndax stocki (Campbell and Clark) vat. B Vish. Theocapsomma comys Foreman Spongosaturnalis ? yaoi Foreman

Assemblage 1 2

3

4

5

m

m

m

i

m

D

m

m

m

m

m

_

_

m

_

_

m

_

_

m

m

m

D

m

D

D

m

m

m

6

145

TABLE I Continued Assemblage

Species

1 Spongosaturnalis hueyi Pessagno Stauralastrum euganeum Squinabol Amphipyndax enesseffi Foreman A mphipyndax plousios Foreman Amphipyndax pyrgodes Renz Foremanina schona Empson-Morin Sciadioeapsa rumseyensis Pessagno Lithostrobus punctulatus Pessagno Lithostrobus rostovzevi Lipman Lithostrobus zhamoidai Kasinzova Stylosphaera pusilla Campbell and Clark Patulibacchium lawsoni Pessagno Stichomitra manifesta Foreman Stichomitra asymbatos Foreman Amphipyndax tylotus Foreman Amphipyndax stocki (Campbell and Clark) var. C Vish. Dictyomitra andersoni (Campbell and Clark) Dictyomitre erassispina (Squinabol) Cornutella californica Campbell and Clark vat. A Renz Cornutelia californica Campbell and Clark var. B Renz Staurodictya fresnoensis Foreman Dictyomitra regina (Campbell and Clark) Dictyomitra rhadina Foreman Dictyomitra pseudoscalaris (Tan Sin Hok) Lithocampe ? eureia Foreman Stichomitra livermorensis Campbell and Clark Stichomitra compsa Foreman Sciadiocapsa ? petasus Foreman Coniforma ? antiochensis Pessagno Clathrocyclas diceros Foreman Clathrocyelas cf. titinnaeformis Campbell and Clark Clathrocyclas ex. gr. lepta Foreman Clathrocyclas hyronia Foreman Clathrocyclas gravis sp. nov. Theocampe vanderhoofi Campbell and Clark Theocampe altamontensis (Campbell and Clark) Theocampe cf. yaoi Taketani Orbiculiforma renillaeformis (Campbell and Clark) Stylosphaera ? minor Clark and Campbell Stylosphaera goruna Sanfilippo and Riedel Protoxiphotractus aft. perplexus Pessagno Amphibrachium cf. mucronatum Lipman Prunobrachium ? incisum Koslova Spongurus moUis sp. nov Stichomitra alamedaensis (Campbell and Clark) Anthocyrtella ? limbata (Koslova) Bathropyramis sanjoaquinensis Campbell and Clark Cromyosphaera vivenkensis Lipman Dictyomitra multicostata Zittel I = D. pseudomacrocephala. aquinensis

2

3

4

5

6

m

D

m

m

m

m

D

m

D

D

m

D

n

m

m

m

m

n

m

m

m

m

m

m

m

m

D

m

m

m

2 = A. bipartitum. 3 = Ps. florens~. 4 = A. enesseff~. 5 = C L diceros. 6 = B. sanjo-

146

occurred, resulting in a distrust of Radiolaria as biostratigraphic markers. At present, significant progress in the elaboration of the Mesozoic radiolarian stratigraphy within the framework of the Pacific region is being made. New work by many Soviet specialists, as well as by Japanese radiolarists, provides good evidence of this advance. Such striking progress in the study of the radiolarians of this region, as well as of many others, first resulted in new methods of extracting radiolarians from hard rocks by means of hydrofluoric acid which were discovered by Dumitrica (1970), and described by Pessagno and Newport (1972), De Wever et al. (1979), De Wever (1982) and other radiolarists. This allowed the study of radiolarians with the scanning electron microscope. Secondly, it resulted in numerous radiolarian-bearing sediments being obtained during the Deep Sea Drilling Project.

Cretaceous radiolarian assemblages of the Bering region Radiolaria were extracted from volcanogenic siliceous rocks (jaspers, cherts, tuffs) by means of hydrofluoric acid. The samples studied are from the Middle--Upper Cretaceous, they have been collected in sections from the Bering Sea region: the Econaic and Olutor tectonic zones of the Koryak highland, the submerged Shirshov Ridge and the northern (Cumrotch Ridge), central (Valagin Ridge) and eastern (Kronozky peninsula) parts of Kamchatka. The preservation of microfossils is satisfactory. The material obtained is illustrated in Plates I--III. Six radiolarian assemblages which appear to be independent of lithofacies have been distinguished. The oldest is the Albian-Turonian radiolarian assemblage with

Pseudodictyomitra

pseudomacrocephala

(Table I). The age of this complex is controlled by planktonic foraminifers such

as: Globigerinelloides ultramicrus, Hedbergella globigerinellinoides, H. aft. amabilis co-occurring with radiolarians. It is possibly a moderate deep-water assemblage as compared with that of the Cuban warm-water zone, because it is characterized by dominant cyrtoidea with thick shell walls and subordinate dicoidea (Vishnevskaya et al., 1982). The following Coniacian--Early Santonian radiolarian assemblage with Archaeospongoprunum bipartitum includes 20 species (Table I). The abundance of polyspheric and spongy skeletons probably points to a peculiar sedimentary environment or is a result of the paleoenvironment (cold aggresive waters) by analogy with the geographic distribution of radiolaria (Kruglikova, 1984). Early Santonian planktonic foraminifers were found together with the radiolarians. The radiolarian assemblage is similar to the Coniacian--Santonian Patellula planoconvexa--Artostrobium urna assemblage of Japan and is well comparable with the assemblage described by Taketani (1982) within Archaeospongoprunum triplum and Orbiculiforrna quadrata zones assigned to the Coniacian--Santonian. The Late Santonian--Early Campanian assemblages with Pseudoaulophacus floresensis contain 30 species (Table 1). The age is confirmed by the following inoceramids: Inoceramus pinniformis, T. cf. transpacificus and ammonites: Gaudryceras cf. tenuiliratum, Sachalinites cf. sachalinensis. The complex is probably of moderate depth, judging by the abundance of spongy skeletons (Prunobrachium, Orbiculiforma, and other) as shown by Empson-Morin (1984). The Middle--Late Campanian assemblage with Amphipyndax enesseffi comprises 30 species. Its age is shown by the widespread Inoceramus schmidti. Plenty of small shells among coarse skeletons are likely an evidence of cold water (Zukanov et al., 1983). The Late Campanian--Early Maastrichtian radiolarian assemblage with Clathrocyclas diceros amounts to 32 species (Table I). The

147

°~

I

I

I

I

o

I

I

I

0

'1 o

I

148

age based on radiolarians is in good agreement with diatoms: Coscinodiscus morenoensis, C. cf. steinyi, Stephanopyxis turris, S. grunowii, Biddulphia cf. primordialis,

Tricertatium deciusi, Hemiaulus polymorphus, Pyxilla speciosa, Micrampula parvula, and silicoflagellates: Luramula furcula, Vallacerta hortoni. It is possibly a cold-water assemblage; this is suggested by the morpholigical structure of the shells: thick-walled shells with rare pores, thick bars, short and sharp spines, massive skeleton. The Late Maastrichtian--Danian assemblage with Bothryopyramis .sanjoaquinensis is represented by 16 species (Table I). A striking peculiarity of this complex are the coarselatticed shells and the predominance of small shells. There is also a Paleocene--Eocene radiolarian assemblage. It differs markedly from the previous one. We suggest that the established radiolarian assemblages are to be used as informal zones for the northeast of the U.S.S.R. A comparison of this radiolarian zonation with previous works is partly given in papers by Vishnevskaya (1985a,b) and shown in Table II. Systematic Three

paleontology species

are

described

as

new.

Clathrocyclas gravis Vishnevskaya sp. nov. (Plate III, 1).

Description: test bell-shaped conical in the third proximal part (cephalo-thorax) and cylindrical in the distal part (abdomen). Cephalis with horn. Abdomen with large pores arranged hexagonally in five transversal rows. The size of the pores gradually increases from cephalis to abdomen. Pores circular to hexagonal in outline with frames. Vertical horn conical, short with sharp tip and the basal 1/4 with four ascending, apically decurrent ridges and circular-ellipsoidal depressions between ridges. Two opposite depressions are very large as for the basal pores, the t w o others are smaller.

Measurements (in #m, made on 8 specimens): total length 2 4 0 - 3 0 0 ; diameter of base of cephalis 90--100; diameter of cephalis near the horn 3 0 - 4 0 ; thorax in widest plane 1 2 0 - 1 5 0 ; in narrowest plane 1 0 0 - 1 1 0 ; length of horn 50; width of abdomen 2 0 0 230; height of abdomen 1 8 0 - 2 0 0 ; diameter of pores 5--25. Remarks: Clathrocyclas gravis sp. nov. differs from Clathrocyclas (Clathrocyclia) tintinnaeformis Campbell and Clark by having a subconical shell, from Clathrocyclas hyronia Foreman by lacking subdivision into segments of abdomen, from the others by having a distinct shape of shell. Holotype: 0297/1, No. 14, U.S.S.R. Bering region. Range (in Bering region): Late Campanian-Maastrichtian. Etymology: from gravis (Latin) pompous.

Sethocyrtis ambiguus Vishnevskaya sp. nov. (Plate I, 2).

Description: test is two-chambered. Cephalis subconical with massive sharp apical horn, thorax subspherical with longitudinal ribs and large circular pores between ribs, not regular in size. Aperture is narrow with thick roller-inner shelf. Horn is vertical subconical near its end with six thin ridges at the base. Cephalis with six pores in a transverse row in upper part and twelve pores near the base, 2--3 pores in one longitudinal row. Pores in thorax with a b o u t 28--30 longitudinal rows, 8 pores for each row. The inner part of the roller is smooth, externally porous. Pores are in 2 irregular rows. Measurements (in pm, made on 4 specimens): total length 40--50; width of cephalis 60--70; length of thorax 8 0 - 1 0 0 ; diameter of the widest part of thorax 1 8 0 - 2 0 0 ; length of horn 45--55; diameter of base of cephalis 8 0 - 9 0 , of thorax 1 5 0 - 1 6 0 , of roller 8 0 90 and of pores 1 0 - 1 5 . Remarks: The species differs from all other species of Sethocyrtis by having different apertural characters, especially thick roller and longitudinal ribs.

149

Holotype: 0 1 3 2 ,

No

15.

U.S.S.R.

Bering

References

region.

Range (in Bering region): C o n i a c i a n - - E a r l y Santonian.

Etymology: f r o m ambiguus (latin) = ambiguous, m y s t e r i o u s .

Spongurus

mollis V i s h n e v s k a y a

sp.

nov.

(Plate III, 1)

Description:

t e s t s p o n g y ellipsoidal-cylindrical, spindle-shape, a b o u t 2.5 t i m e s longer t h a n w i d e , t h r e e - j o i n t e d w i t h t w o equal r o u n d e d lobes f o r m i n g the t w o ends and the central r e g i o n gradually swelling f r o m t h e n e c k o f its w i d e s t level at t h e middle. T h e lobes s e p a r a t e d f r o m t h e central region b y a sulcus. Shells have a s p o n g y f r a m e w o r k o f t h e same s t r u c t u r e , m e s h e s are small and s u b h e x a g o n a l . T h e p o l a r lobe w i t h t w o v e r y s h o r t spines. P y l o m e w i t h o u t spines. Measurements ( i n / z m , m a d e o n 3 specimens): length 2 0 0 - - 2 5 0 ; w i d t h across the widest central p a r t 1 0 0 - - 1 3 0 ; w i d t h in place o f sulcus 8 0 - 9 0 ; across lobes 7 0 - 8 0 ; d i a m e t e r o f p y l o m e 25--30. Remarks: Spongurus mollis n. sp. differs f r o m all o t h e r species o f Spongurus b y having subcylindrical f o r m . Holotype: CH 237, No. 3, U.S.S.R. Bering region. Range (in Bering region): L a t e Maastrichtian-Danian. Etymology: f r o m mollis (adj., latin) = t e n d e r . Acknowledgements

T h e a u t h o r wishes t o t h a n k his colleagues f r o m t h e Oceanic D e p a r t m e n t o f t h e I n s t i t u t e o f t h e L i t h o s p h e r e o f t h e U.S.S.R. A c a d e m y of Sciences and all participants in E U R O R A D - I V f o r t h e i r valuable help. I also wish to express m y g r a t i t u d e t o Drs. P. De Wever and P. D u m i t r i c a f o r reviewing the d r a f t o f t h e above p a p e r and v e r y f r u i t f u l criticism a n d editorial w o r k .

De Wever, P., 1982. Radiolaires du Trias et du Lias de Turquie (Systfimatique, Stratigraphie). Soc. G~ol. Nord Lille Publ., 7, 599 pp. De Wever, P. et al., 1979. Recherches actuelles sur les Radiolaixes en Europe. Ann. Soc. G~ol. Nord Lille, 98: 205--222. Dumitrica, P., 1970. Cryptocephalic and cryptothoracic Nassellaria in some Mesozoic deposits of Romania. Rev. Roum. geol. geophys, geogr., Geol., 14(1):45--124. Empson-Morin, K.M., 1984. Depth and latitude distribution of Radiolaria in Campanian (Late Cretaceous) tropical and subtropical oceans. Micropaleontology, 30(1):87--115. Foreman, H., 1968. Upper Maastrichtian Radiolaria of California. Spec. Pap. Paleontol., 3:1--82. Kasinova, L.I., 1979. Cretaceous Radiolaria of Koryak highland. Soy. Geol., 4:80--85 (in Russian). Kruglikova, S.B., 1984. Paleoecological reconstructions on the base of the radiolarians. In: Morphology, Ecology and Evolution of Radiolarians. Nauka, Leningrad, pp. 41--53 (in Russian). Lipman, R.C., 1952. New date about age of siliceous rocks from the Far East. Rep. Acad. Sci. U.S.S.R., 136(2):23--47 (in Russian). Pessagno Jr., E.A. and Newport, R.L., 1972. A technique for extracting Radiolaria from cherts. Micropaleontology, 13(2): 231--234. Taketani, Y., 1982. Cretaceous radiolarian biostratigraphy of the Urakawa and Obira areas, Hokkaido. Tohoku Univ. Sci. Rep., 2nd Set. (Geol.), 52(1--2): p. 1--76. Vishnevskaya, V.S. et al., 1982. Edad y condiciones de formationes de las silicitas de la zona de Camajuani (Cuba). Cienc. Tierra Espacio, 6: 113--117. Vishnevskaya, V.S., 1985a. Biostratigraphy of Cretaceous volcanogenic-siliceous rocks of U.S.S.R. Bering region on the basis of radiolarians. Pac. Geol., 4:84--93 (in Russian). Vishnevskaya, V.S., 1985b. Comparison of Mesozoic zonal scales of the continents and oceans by radiolarians. Quest. Micropaleontol., 27:188--200 (in Russian). Zhamoida, A.I., 1972. Biostratigraphy of the Mesozoic siliceous series of the East of the U.S.S.R. by study of Radiolaria. Tr. VSEGEI, nov. ser., 183:1--243 (in Russian). Zukanov, N.V., et al., 1984. Composition and age of Shirshov Ridge siliceous rocks (Bering sea). Izv. Acad. Sci. U.S.S.R., Ser. Geol., 11:80--85 (in Russian).