radiolaria - Marum

Radiolaria 14 Bibliography - 1990
The Triassic to Jurassic sedimentary complex in the northern
part of the Tamba Belt, Southwest Japan, is divided into the
Yuragawa, Tsurugaoka, Hisasaka Complexes and the Furuya
Formation. These complexes are composed mainly of melange,
forming a pile of nappes. These melanges, chaotically mixed rock
bodies, have been composed of the constituent element of the
Triassic to Jurassic chert-clastics sequences ranging from pelagic
siliceous rock upward to terrigenous clastic rock. On the basis of
radiolarian biostratigraphy, the age of clastic rocks of these
complexes indicates younging overall toward the structural lower,
namely from the Hisasaka Complex to the Yuragawa Complex. Many
deformation structures are recognized in the melange; layer-parallel
extension and shearing produced disruption of the original layering in
the clastic rocks. Asymmetric deformation structures originating
during the layer-parallel shearing are inferred to have been formed
as a result of the compression probably associated with a northward
underthrusting or southward overthrusting. These lithologic and
structural features suggest that the sedimentary complex in this
area is interpreted to have primarily been formed at an ancient
subduction zone.
Nelson, D.M. & Gordon, L.I. 1990. Distributions of
biogenic silica and dissolved silicic acid in the surface waters
of the Ross Sea, January and February 1990. Antarct. J. U. S.,
25/5, 98-99.
Global mass balances indicate that approximately 75-85
percent of the modern accumulation of biogenic silica in marine
sediments takes place south of the Antarctic Convergence (De
Master 1981; Ledford-Hoffman, De Master, and Nittrouer 1986).
The antarctic and subantarctic are nowhere near this important
quantitatively in the global deposition pattern of organic carbon
(Lisitzin 1972; Holland 1978), and appear to account for no more
than 5 percent of the global-scale photosynthetic production of
organic carbon by phytoplankton (Smith and Nelson 1986). These
mass-balance calculations combine to suggest that the cycles of
siliceous and organic biogenic material in the southern ocean are
decoupled to an extent that is not true in most other oceanic
regions, and that this decoupling makes the Antarctic the main site
of long-term removal of silica from the oceans.
Nishimura, H. 1990. Taxonomic study on Cenozoic
Nassellaria (Radiolaria). Sci. Rep. Inst. Geosci., Univ.
Tsukuba, Sect. B: geol. Sci., 11, 69-172.
Well-preserved and highly diversified Cenozoic nassellarians
extracted from the following formations and deep-sea sediments are
comprehensively studied: Hatatate Formation of Miyagi Prefecture,
Isozaki Formation of Ibaraki Prefecture; Zushi and Kinugasa
Formations of Kanagawa Prefecture; deep-sea bottom sediments at
Lat. 0° 58' S, Long. 18° W, depth 5359 m and at Lat. 0° 55.96' S,
Long. 166°15.77' W, depth 5,405 m. The present author observed
the ultramicrostructures of cephalic wall and skeleton of these
radiolarians with a scanning electron microscope. As a result, the
following three lines of evidence are clarified; (1) three patterns of
growth lines are recognized; (2) traces of the vertical, apical, dorsal,
lateral and secondary lateral rays are detected; (3) elongated rays
of the cephalic skeleton are recognized within the cephalic wall. This
evidence shows that the cephalic skeletal structures are formed in
the earliest growth stage of shell and gradually covered by lamellae.
Therefore, the cephalic skeletal structures are considered to be the
most important criterion for higher taxonomy of nassellarians.
Fifteen types of the cephalic skeletal structures are distinguished in
Cenozoic nassellarians, which are classified into 15 families.
In the present study, 58 genera and 112 species of
nassellarians are studied, of these 6 genera and 4 species are newly
proposed and 52 genera are emended herein. Based upon the
cephalic skeletal structures, 13 families are emended and 2 new
families are proposed herein.
Noble, P. & Renne, P. 1990. Paleoenvironmental and
biostratigraphic significance of siliceous microfossils of the
Permo-Triassic Redding Section, Eastern Klamath Mountains,
California. Mar. Micropaleontol., 15/3-4, 379-391.
Permo-Triassic rocks of the Redding Section, Eastern Klamath
Mountains represent a vertical succession from a shallow water
carbonate environment of the McCloud Limestone to a deeper water
environment of the Pit Formation. This resulted from an episode of
subsidence which started in the Early Permian and continued through
the Middle Triassic. Subsidence is demonstrated by the existence of
a set of progressively deepening lithofacies in Dekkas and basal Pit
cherts. Dekkas cherts are hematitic with abundant sponge spicules
and radiolarians indicative of highly oxygenated waters in full
communication with oceanic circulation. Basal Pit cherts are pyritic,
spicule-poor and fine grained, indicative of poorer circulation and
greater depths. Extensive pyritic black shales of the Pit and Modin
Formations overlie the basal Pit cherts and correspond to a
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restriction of circulation resulting in the stagnation of bottom water
and the development of anoxic conditions. Normal marine circulation
returned briefly in the Late Triassic as evidenced by the Hosselkus
Limestone, a fossiliferous micritic limestone containing abundant
marine fauna, including radiolarians.
Radiolarians recovered from Dekkas cherts are sufficiently well
preserved to yield an age of early Guadalupian, based on Albaillellid
fauna. This fauna was calibrated with a fusulinid fauna collected 7
km south in the lower section of the same member. One new genus
and three new species are described.
O'Dogherty, L. & Martínez-Gallego, J. 1990.
Radiolarios del Cretácico Inferior (Barremense-Albense) en el
sector de Campillo de Arenas (Subbético Medio). Acta
Salmanticensia, 68, 263-275.
The Barremian-Lower Albian Radiolaria fauna from the Campillo
de Arenas area (Middle Subbetic) is studied for the first time. Three
faunal assemblages have been recognized. A lower one (Barremianlower
Aptian) which is dominated by, Sphaerostylus septemporatus,
S. Ianceola, Eucyrtis hanni and Archaeodictyomitra lacrimula. A
middle (upper Aptian) where Thanarla conica and Thanarla pulchra
are the more characteristic species; and a upper one (lower Albian)
with Kozurium ssp. These Radiolarian faunas bear great affinities to
the North California and Central America ones.
Okada, M. 1990. Occurrence of Permian radiolarians from
Ujitawara-cho, southern Kyoto Prefecture. J. geol. Soc.
Japan, 96/11, 937-939. (In Japanese)
Osozawa, S., Sakai, T. & Naito, T. 1990. Miocene
subduction of an active mid-ocean ridge and origin of the
Setogawa ophiolite, Central Japan. J. Geol., 98/5, 763-771.
The Setogawa subduction complex represents the subduction of
an active mid-ocean ridge (the Kula Pacific Ridge) under the Japan
Arc about 20 m.y. ago in the early Miocene. The basalt is youngest in
subzone B3 of the Setogawa Belt and becomes older in both landward
and oceanward subzones. Accumulation time for pelagic sediments
overlying the basalt lengthens in the same two directions. The basalt
of subzones B2 and B3 is directly overlain by or contemporaneous
with the hemipelagic sediments. In subzone B3. the Setogawa
dismembered ophiolite, including basalt, ultramafic rocks, gabbro,
tonalite, and trondhjemite was emplaced from the mid-ocean ridge
near the subduction zone.
Ozvoldová, L. 1990. Radiolarian microfauna from
radiolarites of the Varin part of the west Carpathian Klippen
Belt. Geol. Sb. (Bratislava), 41/3, 295-310.
In the drillhole Smolinske 17 at a depth of 1399—1605 m,
marlstones, marly shales and limestones of Albian age with
radiolarian ostracod and foraminifer microfauna have been found
under Neogene sediments of the Vienna Basin (BieIy et al., 1973).
The composition of the foraminifer microfauna determined by SamueI
(ibidem) suggests its Albian age. The analysis of the well-preserved
pyritized radiolarian microfauna from a depth of 1498-1499 m
indicates also the Albian, probably its middle to upper part.
Ozvoldová, L. 1990. Occurrence of Albian radiolaria in
the underlier of the Vienna Basin. Geol. Sb. (Bratislava),
41/2, 137-154.
Microfaunistic analysis of samples from radiolarites and
radiolarian limestones of the Kysuca succession in the western part
of the Varin stretch of the Klippen Belt at localities Brodno, Sneznica
and Lopusne Pazite has proved the presence of radiolarian
microfauna which can be correlated, according to biostratigraphic
zoning of Baumgartner (1984), with U.A. 7 and U.A. 8
stratigraphically corresponding (Baumgartner, 1987) to the upper
part of the Lower to Upper Oxfordian. A new species ?
Angulobracchia cava n. sp. has been described in the assemblage of
the sample S-4 (Sneznica).
Pessagno, E.A. & Blome, C.D. 1990. Implications of
New Jurassic stratigraphic, geochronometric, and
paleolatitudinal data from the western Klamath terrane (Smith
River and Rogue Valley subterranes). Geology, 18, 665-668.
Combined biostratigraphic, chronostratigraphic, and
geochronometric studies of the Rogue and Galice Formations (Rogue
Valley subterrane, southwestern Oregon) indicate that the
Oxfordian-Kimmeridgian boundary should be placed at 154 +1.5 Ma
rather than at 156 +6 Ma as advocated in the Decade of North
American Geology 1983 geologic time scale. In the Smith River
subterrane (northwestern California, southwestern Oregon), well-