Late Campanian and Early Maastrichtian
ammonites from the white chalk of Kronsmoor (northern Germany) -taxonomy
and stratigraphy
NIEBUHR B.1
in collaboration with ESSER K.
1Bayerische Julius-Maximilians-Universität,
Institut für Paläontologie, Pleicherwall 1, D-97070 Würzburg,
Germany.
niebuhr@mail.uni-wuerzburg.de
ABSTRACT: Hypophylloceras (Neophylloceras)
velledaeforme (Schlüter, 1872), Anagaudryceras lueneburgense
(Schlüter, 1872), Saghalinites wrighti Birkelund, 1965,
Pachydiscus (Pachydiscus) neubergicus (von Hauer,
1858), Menuites cf. wittekindi (Schlüter, 1872),
Diplomoceras cylindraceum (Defrance, 1816), Baculites vertebralis
Lamarck, 1801, Baculites knorrianus Desmarest, 1817, Acanthoscaphites
tridens (Kner, 1848), and Hoploscaphites constrictus (J.
Sowerby, 1877) are described for the first time from Kronsmoor, the
only continuous Campanian-Maastrichtian boundary succession of northern
Germany. Combined with the
slightly younger section at Hemmoor (30 km SW of Kronsmoor), thirteen
ammonites species in all are known to date from the Maastrichtian. The
material studied comprises species from the Upper Campanian Belemnitella
langei to the Lower Maastrichtian Belemnella sumensis zones.
Three species (Baculites vertebralis, Baculites knorrianus,
Hoploscaphites constrictus) occur earlier here than elseswhere
(e.g., Denmark). Menuites cf. wittekindi, formerly known
only from the Nostoceras polyplocum Zone (Upper Campanian), occurs
in the Belemnella lanceolata Zone at Kronsmoor. Pachydiscus
neubergicus and Diplomoceras cylindraceum, two of twelve
markers for the base of the Maastrichtian at Tercis (GSSP, southwestern
France), have their first occurrences at Kronsmoor significantly above
that of Belemnella lanceolata, the belemnite marker for the base
of the stage. Compared with Tercis, were the stage boundary was recommended
between the FOs of both ammonite species, the Campanian - Maastrichtian
boundary at Kronsmoor seems to be located within the Belemnella pseudobtusa
Zone. Thus, the first occurrence of the genus Belemnella
is of Late Campanian age, appearing c. 540 ky earlier than the base
of the Maastrichtian as defined at the GSSP at Tercis.
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Integrated correlation of Late Silurian
(Pridoli s.l.) - Devonian chitinozoans and miospores in the Solimoes
Basin, northern Brazil
GRAHN Y.1, LOBOZIAK S.2,
DE MELO J. H. G.3
1Universidade do Estado do Rio
de Janeiro, Faculdade de Geologia, Bloco A - Sala 4001, Rua Sao Francisco
Xavier 524, Maracana, 20550-013 Rio de Janeiro, R.J., Brazil
2deceased
3Applied Biostratigraphy and Paleoecology
Management of PETROBRAS R & D Center (CENPES/PDEXP/BPA), Ilha do Fundao,
21949-900 Rio de Janeiro, RJ, Brazil
ABSTRACT: Chitinozoans from the Late Silurian
(Pridoli s.l.) and Devonian, and miospores from the Middle and Late
Devonian, have been investigated from the Solim›es Basin in northern
Brazil. Of the 37 chitinozoan species encountered, 16 are retained in
open nomenclature, because of an insufficient number of well-preserved
specimens, and Ramochitina jutaiense is newly described. Three
or four miospore zones have been recognized: the LE - LN and VH zones
of late to latest Famennian age, and a poorly characterized interval
not older than the AP zone of latest Emsian - early Eifelian age. A
regional chitinozoan biozonation, consisting of six zones, is proposed
for the investigated interval. These zones are, from the oldest to the
youngest: concurrent range zone of Ancyrochitina ancyrea and
Ancyrochitina aff. A. libyensis (Pridoli s.l.); interval
range zone of Angochitina filosa (early Lochkovian); concurrent
range zone of Urochitina loboi and Ramochitina jutaiense
sp. nov. (late Lochkovian); concurrent range zone of Ancyrochitina
arirambaense and Alpenachitina eisenacki (Eifelian s.l. -
early Givetian); interval range zone of Angochitina mourai (Frasnian
- middle Famennian); and total range zone of Fungochitina ultima
(late Famennian).
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The Jurassic crinoid genus Cyclocrinus d'Orbigny, 1850:
still an enigma
RADWANSKA U., RADWANSKI A.
Institute of Geology, Warsaw University, Al. Zwirki i Wigury 93, PL-02-089 Warszawa, Poland.
ularadw@geo.uw.edu.pl
ABSTRACT: A rich collection of isolated columnals
and fragmentary pluricolumnals, varying considerably in size, shape,
and sculpture, from the Upper Oxfordian of the Couiavia region (northwestern
Central Poland), is the basis for a critical discussion of the crinoid
genus Cyclocrinus and its species. These are all based on dissociated
columnals with tuberculate articular faces, and all with similar if
not identical arrays of tubercles. The collection studied contains tuberculate
columnals, as well as those with plain articular faces, which acquire
tuberculation when etched with acids. This indicates the corrosional
nature of tuberculation in the newly established species,
Cyclocrinus couiavianus sp.nov., and in all other Cyclocrinus
material. The structure of fragmentary pluricolumnals, whose arching
and branching are reminiscent of root systems of some bourgueticrinids,
would suggest that all Cyclocrinus material represents nothing
else but modified radicular cirrals of unrecognizable members of the
order Bourgueticrinida Sieverts-Doreck, 1953, rather than Cyrtocrinida
or Millericrinida as previously assumed.
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Sievertsella, a replacement
name for Sievertsia Radwanska, 1987 (Echinodermata, Crinoidea),
preoccupied by Sievertsia Smith & Paul, 1982 (Echinodermata,
Cyclocystoidea)
RADWANSKA U.
Institute of Geology, Warsaw University, Al. Zwirki i
Wigury 93, PL-02-089 Warszawa, Poland.
ularadw@geo.uw.edu.pl
ABSTRACT: Over a dozen years ago, in a monograph
on stalkless crinoids from the Korytnica Basin (Middle Miocene; Holy
Cross Mountains, Central Poland), I established (Radwanska 1987) the
genus Sievertsia (type species: Palaeocomaster seranensis
Sieverts, 1933) to include two species of Neogene comasterid comatulids.
This new generic name was proposed in honour of Hertha Sieverts-Doreck,
whose paramount effort and experience in the recognition of some extinct
echinoderms, and crinoids in particular, has remained monumental. Dr.
John W.M. Jagt (Natuurhistorisch Museum Maastricht) has kindly
pointed out to me recently (in litt.) that this name is preoccupied
by Sievertsia Smith & Paul, 1982, erected for a Palaeozoic
cyclocystoid, a member of those enigmatic echinoderms which Sieverts-Doreck
(1951) was also interested in. To comply with ICZN rules (1999; Articles
53.2 and 60.1), I here propose the generic replacement name Sievertsella
nom.nov., preserving the sound of the name of honoured Hertha Sieverts-Doreck
(1899-1991). To date, the genus Sievertsella comprises two species:
Sievertsella seranensis (Sieverts, 1933), being the type by original
designation (Radwanska 1987), from the Pliocene of the Isle of Ceram
(= Seran in German) in the Moluccas, Indonesia (see Sieverts 1933),
and Sievertsella polonica (Radwanska, 1987) from the Miocene of Poland.
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Changes in Paratethyan marine molluscs
at the Early/Middle Miocene transition: diversity, palaeogeography and
palaeoclimate
HARZHAUSER M.1, MANDIC O.2,
ZUSCHIN M.2
1Department of Geology and Palaeontology,
Museum of Natural History, Burgring 7, A-1014, Wien, Austria.
mathias.harzhauser@nhm-wien.ac.at
2Institute of Palaeontology, University
of Vienna, Althanstraße 9, A-1090, Wien, Austria.
ABSTRACT: The transition from the Early Miocene
to the Middle Miocene is a crucial point for the development of mollusc
faunas (gastropods and bivalves) in the Central Paratethys. Here, we
first discuss the confusing and partly contradictory stratigraphic concepts
and correlations of Paratethyan and Mediterranean reference faunas.
Then we show that the interplay of sea level fluctuations, climatic
amelioration, immigrations, and blooms in autochthonous elements causes
a complex pattern of faunal development. We focus on the so-called "Grund
Fauna", which flourished during the Early Badenian and is here
treated as transitional between typical late Early Miocene and typical
Middle Miocene faunas. This faunal type, originally defined in Austria,
is represented within the entire Central Paratethys and is strictly
stratigraphically determined. It developed during the early Middle Miocene
and is interpreted by us to mirror a phase of optimal climatic conditions.
This is most plausible in respect to the marginal position of the Central
Paratethys. As a northern appendix of the early Mediterranean Sea, it
spans a north-south gradient of about 4° latitude and is suggested
to re- present a type of "palaeo-thermometer", which reflects
slight expansions or restrictions of climatic belts. The Langhian climatic
optimum, for example, seems to be reflected within Paratethyan mollusc
faunas by the northward migration of Mediterranean thermophilic species
during the Early Badenian.
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Age, sedimentary environment and palaeogeographical
position of the Late Silurian oolitic beds in the Holy Cross Mountains
(Central Poland)
KOZLOWSKI W.
Institute of Geology, Warsaw University, Al. Zwirki i
Wigury 93, PL-02-089 Warszawa, Poland.
woko@uw.edu.pl
ABSTRACT: A thin sandy-oolitic formation [Jadowniki
Formation (JF)] is described from the Upper Silurian of the Lysogory
Unit, Holy Cross Mountains (Central Poland). Its numerous trilobites
(e.g. Homalonotus knighti, Acastella spinosa) and position
in the lithological column testify for the late Ludfordian age of this
formation. The sedimentary environment of the Jadowniki Formation is
interpreted as extremely shallow - barrier environments with episodes
of emersion and subaerial early diagenesis and erosion. However, these
shallows were not connected with the nearshore belt of Baltica land
and were separated from them by a belt of deep basin sedimentation -the
graptholitic shales. Silurian shallow marine sediments of the Lysogory
Unit were deposited on top of a clastic wedge, which in the Ludlovian
infilled the offshore - deep basin of the SW margin of the East European
Craton. The wedge was probably connected with the process of dockage
of new terranes onto the south-west periphery of the East European Craton.
The second factor that led to the development of shallow marine environments
was probably the uppermost Ludfordian regressive event.
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Nassariid assemblages from the Korytnica
Clays - a useful tool for local stratigraphic correlation
ZLOTNIK M.
Institute of Geology, Warsaw University, Al. Zwirki i
Wigury 93, PL-02-089 Warszawa, Poland.
M.Zlotnik@uw.edu.pl
ABSTRACT: Analysis of the distribution of species
of the family Nassariidae (Gastropoda, Prosobranchia) in the Middle
Miocene Korytnica Clays (Holy Cross Mountains, central Poland) enabled
five nassariid assemblages to be distinguished, viz. the (1) Nassarius
restitutianus, (2) N. restitutianus-korytnicensis, (3) N.
korytnicensis, (4) N. korytnicensis-limatus and (5) Nassarius
schoenni assemblages. The schoenni and korytnicensis-limatus
assemblages occupied the littoral zone of the Korytnica Basin. The remaining
nassariid assemblages inhabited different offshore environments. Nassariid
assemblages appear to be a useful tool for local stratigraphic
correlation as their succession is identical within almost the entire
study area, excluding the littoral zone. The lower limit of one of the
most widespread nassariid assemblages (korytnicensis assemblage)
is proved to be an isochronous surface. The isochronous nature of other
boundaries between the nassariid assemblages recognised in the succession
is also postulated. The entire nassariid sequence is interpreted as
a record of temporal changes in the relative size of two large gastropod
populations: the population of Nassarius restitutianus and the
population of Nassarius korytnicensis. Environmental requirements
of the most abundant nassariids are described in detail.
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