radiolaria - Marum

Radiolaria 14 Bibliography - 1990
recorded in the middle to upper Albian, from scattered occurrences
,and subsequently throughout most of the Cenomanian-Turonian
succession. Spumellarian forms are dominant in all the sections.
Nassellarian forms seem to have thrived in relatively deep-water
environments, in middle neritic to upper bathyal pelagic biotopes,
and have been recovered from upper Albian and uppermost
Cenomanian to middle Turonian sediments. Diatom frustules are only
recorded from upper Cenomanian and lower Turonian deposits. These
seem to have been more abundant in shallower neritic environments.
The onset of the radiolarian assemblages in middle-late Albian times
(with waning low-oxygen pelagic conditions) is thought to be a
response to better developed oceanic circulation pasterns and to a
water mass saturated in dissolved silica, perhaps generated by
deep-sea volcanic processes in the formation of early oceanic crust
and the mid-oceanic ridge in the northern South Atlantic. On the
other hand, the record of radiolarian and diatom tests throughout the
Cenomanian-Turonian succession is commonly associated with
dysaerobic to quasi-anaerobic bottom conditions. This is not only in
keeping with high epipelagic primary productivity in well-oxygenated
surface waters and that the sea water apparently contained a high
level of dissolved silica, but also suggests that the bottom and
interstitial waters were enriched in carbon dioxide, had a low pH and
slightly negative redox-potential (Eh). The overall conditions would
have favoured the biomineralization and post-mortem preservation
of siliceous organisms increasing, therefore, the radiolaria+diatom
/foraminifera ratio in the sediments, which supports the conclusions
of several previous authors.
Kozur, H. & Mostler, H. 1990. Saturnaliacea Deflandre
and some other stratigraphically important radiolaria from
the Hettangian of Lenggries/Isar (Bavaria, Northern
Calcareous Alps). Geol. Pälont. Mitt. Innsbruck, 17, 179-
248.
In the Kirchstein Limestone of the type locality 6.5 km WSW of
Lenggries/Isar (Bavaria) rich radiolarian and sponge spicule
associations have been discovered about 1 m above the Rhaetian
Dachstein Limestone. The radiolarians indicate Hettangian age. All
discovered species of the Saturnaliacea DEFLANDRE, 1953 have
been described. Additionally, the stratigraphically important species
of other radiolarian families have been described. 2 families, 7
genera and 63 species have been newly established.
Lazarus, D. 1990. Middle Miocene to Recent radiolarians
from the Weddell Sea, Antarctica, ODP leg 113. In:
Proceedings of the Ocean Drilling Program, Scientific
Results. (Barker, P.F., Kennett, J.P. et al., Eds.), vol. 113.
College Station, TX (Ocean Drilling Program), pp. 709-727.
Well preserved middle Miocene to Recent radiolarians were
recovered from several sites in the Weddell Sea by ODP(Ocean
Drilling Program) Leg 113. Low rates of sedimentation, hiatuses, and
poor core recovery in some sites are offset by the nearly complete
recovery of a late middle Miocene to late Pliocene section at Site
689 on the Maud Rise. Although a hiatus within the latest Miocene
exists, this site still provides an excellent reference section for
Antarctic biostratigraphy. A detailed radiolarian stratigraphy for the
middle Miocene to late Pliocene of Site 689 is given, together with
supplemental stratigraphic data from ODP Leg 113 Sites 690, 693,
695, 696, and 697. A refined Antarctic zonation for the middle
Miocene to Recent is presented, based on the previous zonations of
Hays (1965), Chen (1975), Weaver(1976b), and Keany (1979).
The late Miocene radiolarian Acrosphaera australis n. sp. is
described and used to define the A. australis zone, ranging from the
first appearance of the nominate species to the last appearance of
Cycladophora spongothorax (Chen) Lombari and Lazarus 1988. The
species Botryopera deflandrei Petrushevskaya 1975 is transferred
to Antarctissa deflandrei (Petrushevskaya) n. comb.
Ling, H.Y. & Lazarus, D.B. 1990. Cretaceous
radiolaria from the Weddell Sea: Leg 113 of the Ocean
Drilling Program. In: Proceedings of the Ocean Drilling
Program, Scientific Results. (Barker, P.F., Kennett, J.P. et
al., Eds.), vol. 113. College Station, TX (Ocean Drilling
Program), pp. 353-363.
Unusually well preserved Cretaceous radiolarians are observed
in the subsurface sections from two drilled sites in the Weddell Sea
collected during Leg 113 of the Ocean Drilling Program. Radiolarians
from the lithified calcareous chalk of Hole 689B represent the first
Campanian-Maestrichtian assemblage which is characterized by
abundant Cromyodruppa ? concentrica, Dictyomitra multicostata,
and Protostichocapsa stocki. Abundant Pseudodictyomitra
pentacolaensis and Diacanthocapsa sp. I, on the other hand, are the
main constituents of the assemblage from the latest Aptian/earliest
Albian diatomite of Hole 693B. These represent the oldest and the
highest-latitude reported radiolarian occurrences from the Atlantic
sector of the Antarctic Ocean. The assemblages are marked by their
low diversity and an absence of low- to mid-latitude zonal indices.
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Marcucci, M. & Marri, C. 1990. Radiolarian
assemblages in ophiolite sequences of southern Tuscany: new
data. Ofioliti, 15/1, 185-190.
The ophiolites of the Northern Apennines are topped by a
siliceous sedimentary formation: the M. Alpe Cherts (Abbate and
Sagri, 1970). This paper concerns the age of the base of this
formation in Southern Tuscany, that is the onset of siliceous
deposition above the ophiolite sequence in this area. Datings are
based on radiolarian biostratigraphy of Baumgartner (1984; 1987).
Three new sections of the M. Alpe Cherts are examined: Il Romito,
near Leghorn (Fig. 2a), Capannelle, near Paganico (Fig. 2b), Sovana-
Elmo, SE of M. Amiata (Fig. 2c). Other sections in Southern Tuscany
have been previously studied: Elba Island (Baumgartner, 1984; Conti
and Marcucci, 1986), M. Vitalba (Picchi, 198S), Riparbella and
Quercianella (Nozzoli, 1986), Murlo (Conti and Marcucci, 1986),
(Fig. 1).
Margulis, L., Corliss, J.O., Melkonian, M. &
Chapman, D.J. 1990. Handbook of Protoctista: the
structure, cultivation, habitats, and life histories of the
eukaryotic microorganisms and their descendants exclusive of
animals, plants and fungi: a guide to the algae, ciliates,
foraminifera, sporozoa, water molds, slime molds, and the
other protoctists. The Jones and Barlett Series in Life
Sciences, Jones and Barlett Publishers Boston. , 914 p.
Matsuoka, A. 1990. Explanatory Notes, Shipboard
Scientific Party. In: Proceedings of the Ocean Drilling
Program, Initial Reports. (Larson, R.L., Lancelot, Y. et al.,
Eds.), vol. 129. College Station, TX (Ocean Drilling
Program), pp. 5-29.
In this chapter, we have assembled information that will help
the reader understand the basis for our preliminary conclusions and
also help the interested investigator select samples for further
analysis. This information concerns only shipboard operations and
analyses described in the site chapters in the Initial Reports volume
of the Leg 129 Proceedings of the Ocean Drilling Program. Methods
used by various investigators for shore-based analysis of Leg 129
data will be detailed in the individual scientific contributions
published in the Scientific Results volume.
Cenozoic Zonation: Radiolarian zonal assignments of Cenozoic
samples were based on the tropical zonation of Riedel and Sanfilippo
(1978) and subsequent modification in Sanfilippo et al. (1985).
Calibration of this zonation with chronostratigraphy and
geochronology follows Berggren et al. (1985a, 1985b).
Mesozoic Zonation: Figures 9 and 10 show the radiolarian
zonation scheme adopted during Leg 129 for Middle Jurassic to
Cretaceous sediments and the calibration with the geochronology of
Kent and Gradstein (1985). The zonation of Sanfilippo and Riedel
(198S) was applied to the Cretaceous sediments except for the
Berriasian and early Valanginian. For the Middle Jurassic to early
Valanginian interval, the radiolarian zonation of Matsuoka and Yao
(1985, 1986) was adopted with modifications. The lowermost
Cretaceous Pseudodictyomitra carpatica Zone is here defined as an
interval zone, although it was originally defined as an assemblage
zone (Matsuoka and Yao, 1985). Its base and top are limited by the
first occurrences of P. carpatica and Cecrops septemporatus,
respectively. The top of the uppermost Jurassic Pseudodictyomitra
primitiva Zone is defined by the first occurrence of P. carpatica .
Age determinations of sediments for the Middle Jurassic to
early Valanginian interval are tentative because radiolarian zones of
this interval are not sufficiently dated by other age diagnostic
fossils. Age assignments of sediments depended largely on
correlation of Matsuoka and Yao's zonation with Baumgartner's
(1984, 1987) zonation. His zonation was based primarily on his
research of Atlantic and Mediterranean Tethys regions where
radiolarian-bearing sequences contain other age diagnostic fossils.
Matsuoka, A. & Oji, T. 1990. Middle Jurassic radiolaria
fossils from the Magisawa Formation in the Taro Belt, North
Kitakami Mountains. J. geol. Soc. Japan, 96/3, 239-241. (in
Japanese)
Matsuoka, A. & Yao, A. 1990. Southern Chichibu
Terrane. In: Pre-Cretaceous Terranes of Japan. Publication of
IGCP Project No. 224: Pre-Jurassic Evolution of Eastern Asia.
(Ichikawa, K., Mizutani, S., Hara, I., Hada, S. & Yao, A.,
Eds.). IGCP Project 224, Osaka, Japan. pp. 203-216.
The Southern Chichibu Terrane (Fig. l) occupies southern
marginal portion of the Jurassic-early Cretaceous terranes of
Southwest Japan. Until 1970s, rocks in the terrane were believed to
contain a small amount of age-diagnostic fossils except for late