radiolaria - Marum

Bibliography - 1993 Radiolaria 14
Osozawa, S. & Okamura, M. 1993. New radiolarian
ages from the Troodos ophiolite and their tectonic
implications. Island Arc, 2/1, 1-6.
Newly obtained radiolarian biostratigraphic age combined with
previous isotopic age of the Troodos ophiolite shows that the
ophiolite becomes systematically younger from east to west:
Turonian, early Campanian, and late Campanian. The youngest late
Campanian part of the ophiolite is directly covered by the
volcaniclastic sediment derived from an active island arc, whereas
the older part is covered by pelagic radiolarite. These facts
constitute evidence that the Troodos ophiolite was probably
emplaced during the subduction of an active spreading ridge.
Pessagno, E.A., Blome, C.D., Hull, D.M. & Six,
W.M. 1993. Jurassic Radiolaria from the Josephine
ophiolite and overlying strata, Smith River subterrane
(Klamath Mountains), northwestern California and
southwestern Oregon. Micropaleontology, 39/2, 93-166.
This report deals with me radiolarian assemblage occurring
within the Josephine ophiolite and in overlying sedimentary strata in
the Western Klamath terrane, Smith River subterrane, northwestern
California. Twenty-seven new species, eight new genera, and one new
family (Bernoulliidae, n. fam.) are described from this succession. An
emended definition is given for Parvicingula Pessagno and a new
name is given for Andromeda Baumgartner. In addition, a revised
radiolarian zonation is presented for the Middle and Upper Jurassic.
This new zonal scheme can be linked to both zonal schemes in Japan
and Europe via first or last occurrence biohorizons of diagnostic
taxa. Radiolarian biostratigraphic data from the Smith River and
Rogue Valley subterranes is related to co-occurring megafossil
chronostratigraphic data and to U/Pb geochronometry. Range,
occurrence, and relative abundance of the more important taxa are
shown in the text-figures. This investigation also establishes that
well-preserved Radiolaria can be extracted from strata exposed to
prehnite-pumpellyite facies metamorphism. Moreover,
paleobiogeographic data are presented to substantiate tectonic
transport of the Western Klamath terrane from low latitudes to high
latitudes during the course of the Middle and Late Jurassic
(Oxfordian-Callovian).
Popova, I.M. 1993. Significance and paleoecological
interpretations of early-middle Miocene radiolarians from
south Sakhalin, Russia. In: Radiolaria of giant and subgiant
fields in Asia. Nazarov Memorial Volume. (Blueford, J.R. &
Murchey, B.L., Eds.), Micropaleontology, special
Publication vol. 6. Micropaleontology Press, American
Museum of Natural History, New York. pp. 161-174.
Radiolarians from the deposits of five south Sakhalins sections
were studied. Taxa found indicated a late early Miocene to early
middle Miocene age of the Maruyamskaya, Kurashiidkaya, and
Sertunaiskaya suites. The comparison of the South Sakhalin
radiolarian assemblages with the same age assemblages from the
Deep Sea Drilling Project Holes 436 (Leg 58) and 438B (Leg 57)
show a large taxonomic similarity especially from the Larcopyle
polyacantha, Sphaeropyle rohusta and Eucyrtidium inflatum zones.
Facies changes and radiolarian assemblages in sections from the
Krilyon Peninsula and the central part of Sakhalin Island show that
early middle Miocene represents a phase of peak paleobasin
transgression. Comparing radiolarians from similar age deposits
from the Kuril, Japanese and Sakhalin Islands suggest a global
oceanic level rise. The comparison of this data with the available
scale of sea level fluctuations of the eastern Pacific near North
America indicates possible synchronisms of middle Miocene
transgressive phases in the northwest and northeast Pacific
sectors.
Saito, M. 1993. Geological significance of the "Toishitype"
shale in the evolution of the Jurassic melanges in the
Kuze area, western Mino Terrane, central Japan. Bull. geol.
Surv. Japan, 44/9, 571-596. (in Japanese)
Saito, M., Sugiyama, K. & Sato, Y. 1993.
Cretaceous radiolarians from the Shimanto Supergroup in
eastern Kagoshima Prefecture, and their geological
significance. J. geol. Soc. Japan, 99/12, 1037-1040. (in
Japanese)
Saito, M., Teraoka, Y., Miyazaki, K. &
Toshimitsu, S. 1993. Radiolarian fossils from the
Nishikawauchi formation in the Onogawa Basin east Kyushu,
and their geological significance. J. geol. Soc. Japan, 99/6,
479-482. (in Japanese)
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Saito, M. & Tsukamoto, H. 1993. Chert breccia, its
occurrence and radiolarian fossils in the Hichiso-Mugi area,
central Mino Terrane, central Japan. J. geol. Soc. Japan,
99/2, 117-133. (in Japanese)
A detailed geological survey has revealed that the chert breccia
conformably covers the Jurassic sandstone in the Hichiso-Mugi area.
It shows that the chert-clastic sequence in the Kamiaso Unit
consists of Early Triassic banded claystone, Middle Triassic to early
Middle Jurassic chert, Middle Jurassic siliceous shale and shale, late
Middle to Late (?) Jurassic turbidite and sandstone, and chert
breccia in the ascending order. On the basis of field and laboratory
evidence and the knowledge of the currently active subduction
zones, the sedimentary process of chert and chert-limestone
breccia formation is discussed. Clasts of the breccias came from
the uppermost part of accretionaly complex and were supplied to the
trench by submarine current in a submarine canyon or gravitational
sliding on it.
Sakakibara, M., Hori, R.S. & Murakami, T. 1993.
Evidence from radiolarian chert xenoliths for post-Early
Jurassic volcanism of the Mikabu greenrocks, Okuki area,
western Shikoku, Japan. J. geol. Soc. Japan, 99/10, 831-
833. (in Japanese)
Sakakibara, M., Isozaki, Y., Nanayama, F. &
Narui, E. 1993. Radiolarian age of greenrock-chertlimestone
sequence and its accretionary prodess of the Nikoro
Group in the Tokoro belt, eastern Hokkaido, Japan. J. geol.
Soc. Japan, 99, 615-627. (in Japanese)
Sarnthein, M. & Faugères, J.C. 1993. Radiolarian
contourites record Eocene AABW circulation in the equatorial
East Atlantic. In: Contourites and bottom currents. (Stow,
D.A.V. & Faugeres, J.C., Eds.), vol. 82/1-4. Sedimentary
Geology, pp. 145-155.
50 m of Middle Eocene pure radiolarian ooze were drilled at ODP
Site 660 in the equatorial East Atlantic, 80 km northeast of the
Kane Gap. The oozes comprise a 10 m high and 2 km broad mound of
seismic reverberations, covered by manganese-rich sediment, and
contain trace amounts of sponge spicules and diatoms, negligible
organic carbon (0.15%), clay, and variable amounts of pyrite. The
yellow to pale brown silty sediments are relatively coarse-grained
(30-45% coarser than 6 µm), little bioturbated, and commonly
massive or laminated on a cm-scale. The unlithified radiolarian ooze
may indicate an interval of high oceanic productivity, probably linked
to a palaeoposition of Site 660 close to the equatorial upwelling belt
during Middle Eocene time. The absence of organic matter, however,
and both the laminated bedding and the mound-like structure of the
deposit on the lower slope of a continental rise indicate deposition
by relatively intense contour currents of oxygen-rich deep water,
which passed through the Kane Gap, winnowed the fine clay fraction,
and prevented the preservation of organic carbon. The ooze may be
either a contourite-lag deposit, or a contourite accumulation of
displaced radiolarians, originating south of the Kane Gap and being
deposited in its northern lee, thus documenting the passage of a
strong cross-equatorial bottom-water current formed near
Antarctica. These Eocene contourites may be an analogue for
ancient radiolarites in the Tethyan Ocean.
Sashida, K., Igo, H., Adachi, S., Koike, T.,
Hisad, K.I. & Nakornsri, N. 1993. Occurrences of
Paleozoic and Mesozoic radiolarians from Thailand and
Malaysia and its geologic significance (preliminary report).
N. Osaka Micropaleont. spec. Vol., 9, 1-17. (in Japanese)
Sashida, K., Igo, H., Hisada, K.I., Nakornsri, N.
& Amponmaha, A. 1993. Occurrence of Paleozoic and
early Mesozoic Radiolaria in Thailand (preliminary report). J.
Southeast Asian Earth Sc., 8/1-4, 97-108.
Paleozoic and Early Mesozoic radiolarians are newly recovered
from chert and associated fine-grained clastic rocks in Thailand.
This study clarifies the geologic age of these radiolarian rocks ant
their paleogeographical and geotectonic significance. Devonian,
Early Carboniferous ant Permian radiolarians were found in the "Fang
Chert" which outcrops along the Chiang Mai-Fang Road, upper north
Thailand. Early Carboniferous radiolarians were recovered from a
sequence of tuffaceous shale ant chert exposed in the Pak Chom
area along the Mekong River, and well-preserved Late Devonian ant
Early Carboniferous radiolarians were also recovered from cherts
exposed along the Pak Chom-Loei Road near Phu Laem, north of Loei,
in northeast Thailant. These Devonian to Carboniferous radiolarian
faunas are apparently identical with those reported from eastern and
western Australia. Well-preserved Early Triassic conodonts and