The Middle Cambrian paradoxidid trilobite Hydrocephalus from Jämtland, central Sweden
RUSHTON A.W.A.1, WEIDNER T.2
1The Natural History Museum, Cromwell Road, London SW7 5BD, UK.
A.Rushton@nhm.ac.uk
2Ravnholtvej 23, Rarup, DK-7130 Juelsminde, Denmark.
to.we@paradis.dk
ABSTRACT: A new paradoxidid species, Hydrocephalus vikensis, is described from the lower Middle Cambrian
praecurrens Zone in Jämtland, central Sweden. It is contrasted with typical Hydrocephalus species and shows
features that recall Paradoxides. The genus Hydrocephalus BARRANDE is discussed; the validity of the
related genus Rejkocephalus KORDULE is considered to be doubtful. The associated fauna is listed and
an agnostoid that differs slightly from Condylopyge regia (SJÖGREN) is illustrated.
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Coelacanths (Actinistia, Sarcopterygii) from the Famennian (Upper Devonian) of the Holy Cross Mountains, Poland
SZREK P.
Institute of Geology, University of Warsaw, Zwirki i Wigury Str. 93, PL-02-089 Warszawa. Poland.
piotr.szrek@uw.edu.pl
ABSTRACT: Coelacanth fishes from the Upper Devonian of the Holy Cross Mountains, Poland, are described. The
material consists of isolated incomplete lower jaws, gular plates, an entopterygoid and urohyal. The isolated
lower jaws belong to Diplocercides kayseri (VON KOENEN, 1895). The other coelacanth remains are
referred to Diplocercides sp. indet. All specimens are Famennian in age (Early Palmatolepis rhomboidea conodont
Zone), representing a time when almost all of the Holy Cross Mountains carbonate platform was
drowned. Because of the shallow-water living conditions preferred by the group it is assumed that these
coelacanths were restricted to isolated, small submarine swells, which still existed in that region in the latest
Devonian, and that their carcasses were then subjected to post-mortem transport into the deeper areas.
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Strike-slip faulting in the Kielce Unit, Holy Cross Mountains, central Poland
KONON A.
Institute of Geology, University of Warsaw, Zwirki i Wigury Str. 93, PL-02-089 Warszawa, Poland.
Andrzej.Konon@uw.edu.pl
ABSTRACT: Strike-slip faults and associated tectonic structures have been investigated in the Holy Cross Mountains
fold belt (HCM), which is located eastwards of the Variscan foreland basin. The strike-slip fault sets
form a complex network, which developed during two faulting stages: in Late Palaeozoic (I) and
Maastrichtian/Palaeocene (II) times.
The Late Palaeozoic fault pattern formed as a result of at least two strike-slip events: I-1 and I-2.
During the first event (I-1), a N-S-striking dextral strike-slip fault set and a NNE-SSW to NE-SW-striking
sinistral strike-slip fault set developed. During the next event (I-2), dextral strike slip occurred along
the WNW-ESE-striking longitudinal master faults and formed a NW-SE to NNW-SSE-striking sinistral
secondary strike-slip fault set. During this event, in zones north and south of the Holy Cross Fault, faultbounded
blocks developed which were rotated dextrally as a result of further displacements. The strikeslip
fault network was overprinted during the Maastrichtian/Palaeocene second strike-slip stage (II).
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First record of the late Campanian heteromorph ammonite Nostoceras hyatti from the Alpine Cretaceous (Grünbach, Gosau Group, Lower Austria)
SUMMESBERGER H.1, MACHALSKI M.2, WAGREICH M.3
1Naturhistorisches Museum Wien, Burgring 7, A-1010 Wien, Austria.
herbert.summesberger@nhm-wien.ac.at
2Institute of Paleobiology, Polish Academy of Sciences, ul. Twarda 51/55, PL-00-818 Warszawa, Poland.
mach@twarda.pan.pl
3Universitat Wien, Department für Geodynamik und Sedimentologie, Althanstr., 14, A-1090 Wien, Austria.
Michel.Wagreich@uni.vie.ac.at
ABSTRACT: The heteromorph ammonite Nostoceras (Nostoceras) hyatti is described for the first time from the
Piesting Formation (Gosau Group; Upper Cretaceous) at Grünbach along the eastern margin of the
Northern Calcareous Alps, Lower Austria. This record significantly extends the geographic range of this
late Campanian marker species; it was not previously known from the Alpine Cretaceous. Moreover, it
corroborates earlier age assignments as late Campanian of the (lower) part of the Piesting Formation.
A matrix sample taken from the specimen studied has yielded taxa whose range covers zones CC20 to
CC23, or UC 15tp to UC18, of the standard nannofossil zonation.
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The Upper Albian ammonite succession in the Montlaux section, Hautes-Alpes, France
KENNEDY W. J.1, LATIL J.-L.2
1Oxford University Museum of Natural History, Parks Road, Oxford, OX1 3PW, United Kingdom.
jim.kennedy@oum.ox.ac.uk
2Le Maupas, F-05300 Lazer, France.
ABSTRACT: A 100 metre succession of Upper Upper Albian sediments in the Montlaux section (les Gipieres-
Champfleury), Alpes-de-Haute Provence, France yielded a series of ammonites that provide unequivocal
evidence for a Mortoniceras (Subschloenbachia) rostratum ammonite Zone succeeded by a Mortoniceras
(Subschloenbachia) perinflatum ammonite Zone. On this basis, and evidence from successions described
previously, the classic Upper Upper Albian Stoliczkaia dispar Zone is replaced by a sequence, from oldest
to youngest, of Mortoniceras (Mortoniceras) fallax, Mortoniceras (Subschloenbachia) rostratum,
Mortoniceras (Subschloenbachia) perinflatum and Arrhaphoceras (Praeschloenbachia) briacensis Zones.
The following species are described: Anagaudryceras sacya (FORBES, 1846), Desmoceras latidorsatum
(MICHELIN, 1838), Puzosia (Puzosia) mayoriana (D'ORBIGNY, 1841), Pleurohoplites renauxianus
(D'ORBIGNY, 1840), Arrhaphoceras sp., Discohoplites simplex WRIGHT & WRIGHT, 1949, Discohoplites subfalcatus
(SEMENOV, 1899), Mortoniceras (Subschloenbachia) rostratum (J.SOWERBY, 1817), Mortoniceras
(Subschloenbachia) perinflatum (SPATH, 1922b), Stoliczkaia (Stoliczkaia) dispar (D’ORBIGNY, 1841),
Stoliczkaia (Stoliczkaia) clavigera NEUMAYR, 1875, Anisoceras armatum (J.SOWERBY, 1817), Anisoceras perarmatum
PICTET & CAMPICHE, 1861, Anisoceras pseudoelegans PICTET & CAMPICHE, 1861, Idiohamites elegantulus
SPATH, 1939, Hamites venetzianus PICTET, 1847, Lechites (L.) gaudini (PICTET & CAMPICHE, 1861),
Lechites (L.) moreti BREISTROFFER, 1936, Mariella (Mariella) bergeri (BRONGNIART, 1822), Ostlingoceras
(Ostlingoceras) puzosianum (D'ORBIGNY, 1842), and Scaphites (Scaphites) sp.
GRAY, 1840 are presented.
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Fold-thrust-belt geometry and detailed structural evolution of the Silesian nappe - eastern part of the Polish Outer Carpathians (Bieszczady Mts.)
RUBINKIEWICZ J.
Institute of Geology, University of Warsaw, Zwirki i Wigury Str., 93 PL-02-089 Warszawa, Poland.
Jacek.Rubinkiewicz@uw.edu.pl
ABSTRACT: On the basis of field studies of mesoscopic structures, and analysis of radar and aerial photos together with
seismic data, the structure and structural evolution of a part of the Silesian nappe was established. In the
study area the Silesian nappe comprises two tectonic units: the Central Carpathian Depression and the
Fore-Dukla thrust sheet, separated by a fault. The Central Carpathian Depression is built of several mapscale
slices. The slices comprise map-scale NE-verging anticlines, with additional synclines to the south-east.
The slices are separated by steeply dipping forelimb-thrusts, which connect together at a depth of ca. 6-7
km into a single sole thrust and form a leading imbricate fan. To the west of the Rabe-Baligród fault zone
the fault between the Central Carpathian Depression and the Fore-Dukla thrust sheet is a typical thrust.
Eastwards from this fault zone it becomes a steeply NE-dipping normal fault. The Silesian nappe is cut by
map-scale oblique and transverse, mainly strike-slip faults - some of them are tear faults. Longitudinal
strike-slip faults indicate dextral movement along the pre-existing thrusts. The structural evolution of the
Silesian nappe comprises here eight pre-, syn- and post-orogenic stages beginning with the formation of
clastic veins, followed by folding, thrusting, strike-slip faulting and terminating with normal faulting.
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The onset of orogenic activity recorded in the Krosno shales from the Grybow unit (Polish Outer Carpathians)
BOJANOWSKI M.J.
Faculty of Geology, University of Warsaw, Zwirki i Wigury Str. 93, PL-02-089 Warszawa, Poland.
mcbojan@uw.edu.pl
ABSTRACT: The Krosno shales were deposited synorogenically in front of an accretionary prism as interchannel flysch
facies on a north-dipping slope that constituted the southern marginal part of the Silesian basin. The
turbidite flows originated from channelised currents and probably also as separate sedimentation events
from slow, dilute "sheet" flows derived from a linear source (probably a shelf-edge). In the background
continuous hemipelagic deposition took place and there were two periods when pelagic sedimentation
prevailed. Mean accumulation rate of the entire succession was moderate: from 8 to 11 cm/ky. The
source rocks were Jurassic to Eocene sedimentary rocks. Geochemical data (La, Th and Sc contents)
point to a continental island arc as the original source of the detrital material. Soft-sediment deformations
and methane-related authigenic carbonates that are also present in this succession evidence the
migration of methane-charged fluids through the sediment column. This fluid expulsion was probably
provoked by orogenic activity, i.e. the formation of an accretionary prism.
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Placer gold and other economic minerals from the remnants of palaeofan deposits in the foreland of the East Sudetes, Poland
WIERCHOWIEC J.
Institute of Geology, University of Warsaw, Zwirki i Wigury Str. 93. PL-02-089 Warszawa. Poland.
Jan.Wierchowiec@uw.edu.pl
ABSTRACT: Gold-bearing palaeofan deposits in the East Sudetic Foreland region are associated with the White
Gravel series, which is the richest gold-bearing horizon. The remnants of the White Gravels in the vicinity
of Gieralcice and Slawniowice contain between 0.33 g/m3 Au near the base and <0.05 g/m3 Au in the
upper part. The gold is associated with other heavy minerals, such as Fe-Ti oxides (magnetite, ilmenite,
and hematite), zircon and rutile. Concentration of these minerals increases significantly with depth and
three-quarters of the total gold is found in the lower half of the palaeofan deposits. The alluvial palaeofan
placers were formed by repeated scouring and reconcentration of resistant heavy minerals from a
number of sources, including pre-existing placers and bedrock. The gold grains are composed of variable
proportions of Au and Ag with trace amounts of Cu, Te and Se. Rims have high gold (>93 wt %
Au) and low silver (<6 wt % Ag) contents, whereas cores contain average 85 wt % Au and 14 wt % Ag.
Porous gold grains are homogeneous and of high purity (>95 wt % Au). The bedrock source of gold is
probably related to quartz veins in Palaeozoic schist and quartzite. There are several local point sources
of gold, mainly quartz veins of the Zlaty Chlum Massif. Data presented for the Gieralcice–Slawniowice
palaeofan placers may be useful for prospecting and exploration for similar deposits.
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