The Devonian ofWestern Karakorum (Pakistan)
GAETANI M.1, MAWSON R.2, SCIUNNACH D.3, TALENT J.A.2
1Dipartimento di Scienze della Terra, Universita di Milano, Via Mangiagalli 34, 20133 Milano, Italy.
maurizio.gaetani@unimi.it
2Department of Earth and Planetary Sciences, Macquarie University, NSW 2109, Australia
3Regione Lombardia, Infrastruttura per l' Informazione Territoriale, Via Sassetti 32, 20124 Milano, Italy
ABSTRACT: Devonian rocks crop out in several thrust sheets in the sedimentary belt of North-Western Karakorum, both to the
south and to the north of the Reshun Fault.Gentlymetamorphosed Devonian dolostones and volcanics are also present
in the Tash Kupruk Zone north of the thrust sheet system. The most complete succession is found in the Karambar
Thrust sheet where dolostones and recrystallized limestones (Vandanil Formation) lie above the black shales
and siltstones of the Baroghil Group. The age of theVandanil Formation is poorly defined, approximating latest Silurian
or earliest Devonian at its base and proven to be Pragian in the 4th of its 5 lithozones. The overlying Chilmarabad
Formation is divided into two members. The lower member is a mixed siliciclastic-carbonate package, present in
most southern and western thrust sheets. The upper member is ubiquitous; it consists of dolostones, often stromatolitic.
The calcareous part of the Tash Kupruk Zone consists of similar facies. The carbonate flats of the Chilmarabad
Formation display a trend towards emersion towards the top, and are overlain, with regional unconformity, by the
basal unit of the Shogram Formation. The base of the latter consists of arenite and fine conglomerate (deposited in
an alluvial setting) overlain by alternating marine bioclastic limestones and litharenites with one or two coral bafflestones
in the middle to upper part. The age of the lowermost part of the Shogram Formation is Givetian, extending
through the Frasnian and seemingly into the Famennian, but the last is poorly documented (contrasting with the
classic Shogram and Kuragh sections of Chitral); it reflects a return to fine terrigenous input.
The inferred palaeogeography accords with the Northern Karakorum having been part of the Gondwana margin
during the Devonian.Awide,mostly calcareous platform, characterised extensive areas of the Karakorum, Central
Pamir, Badakhshan and, in a minor way, Central Afghanistan (Helmand Block). The sandstone petrography
suggests that clastics polluting the carbonates originated from erosion of a pre-existing sedimentary cover. During
theGivetian a first rifting episode, possibly echoing the opening of an ocean to the east, affected thewhole area,with
volcanic outpourings in the rifts, while eroding shoulders fed the basins, though never extending as deep as the crystalline
basement. A minor volcanic input is also recorded. The tectonic pulse almost ceased during the Frasnian,
gradually resuming towards the end of the Devonian.
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The mid-Frasnian subsidence pulse in the Lublin Basin (SE Poland): sedimentary record, conodont biostratigraphy and regional significance
NARKIEWICZ K., NARKIEWICZ M.
Polish Geological Institute, Rakowiecka 4, PL-00-975 Warszawa, Poland.
Katarzyna.Narkiewicz@pgi.gov.pl
Marek.Narkiewicz@pgi.gov.pl
ABSTRACT: Most of the thickness of Frasnian sediments in the central segment of the Lublin Basin, i.e. up to 300 metres, is
represented by a single transgressive-regressive Cycle VIa, developed in the carbonate-sulphate platform facies.
The age of the transgressive part falls into the interval between the upper part of the Upper hassi Zone and the jamieae
Zone, whereas the upper boundary runs between the upper part of the Lower rhenana Zone and the lower part of
the Upper rhenana Zone. Basin architecture and conodont biostratigraphic data confirm the tectonic nature of the
cycle, which represents a short-termincrease in Frasnian subsidence and depositional rates. Based on the conodont
data, it is plausible that the onset of the tectonic subsidence in the Lublin Basin and the incipient Pripyat Graben
rifting correspond closely in age. They can thus be attributed to the common tectonic mechanism of regional extension
in the south-west part of the East European Platform. The lack of any Late Devonian magmatic activity in
the Lublin Basin and the synchronous development of this basin with the Pripyat Graben favour the idea that intraplate
stresses were the primary factors controlling subsidence in both depocentres during themid Frasnian to Famennian.
The hypotheticalmantle plume could havemerely amplified the effects of crustal extension in the Pripyat
Graben, thus facilitating a typical rift development.
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Growth forms and distribution patterns of stromatoporoids exposed on Devonian palaeobottom surfaces; Holy Cross Mountains, central Poland
LUCZYNSKI P.
Warsaw University, Institute of Geology, Al. Zwirki i Wigury 93, 02-089 Warszawa, Poland.
Piotr.Luczynski@uw.edu.pl
ABSTRACT: Well preserved palaeobottomsurfaceswith stromatoporoids are exposed in twoDevonian localities in theHoly Cross
Mountains in central Poland: Skały and Bolechowice-Panek quarries. The stromatoporoids were subjected tomorphometric
analysis and distribution studies. Stromatoporoids were studied hitherto only in vertical cross sections;
the study of three-dimensional stromatoporoid domes has created a need to introduce a new set of parameters describing
their shapes, which includes: horizontal length and width, vertical height, elongation ratio and elongation
azimuth. In order to make the measurements made by various methods comparable, and thus to allow comparable
interpretations, recalculation formulas have been presented. Comparison of the results obtained by the two methods
indicates that the measurements made in vertical cross sections substantially bias the dimensions and shapes
of the stromatoporoids, which may influence stromatoporoid-based palaeoenvironmental reconstructions. The results
of the measurements were interpreted in terms of palaeonvironmental conditions. In Bolechowice-Panek the
stromatoporoids lived in a quiet shallow water setting with a low and stable sedimentation rate. In Skały the stromatoporoids
grew in a shallow subtidal setting and located themselves on parallel ripples,most probably to escape
being buried by deposits accumulating in inter-ripple depressions.
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Late Famennian ?Chaetosalpinx in Yavorskia (Tabulata): the youngest record of tabulate endobionts
ZAPALSKI M.K.1,2, PINTE E.2, MISTIAEN B.2
1Faculty of Geology, Warsaw University, Zwirki i Wigury 93, PL-02-089 Warszawa, Poland.
m.zapalski@uw.edu.pl
2Laboratoire de Paleontologie stratigraphique FLST and ISA, UMR 8157 "Geosystemes" du CNRS.
41,rue du Port, 59046 Lille cedex, France
ABSTRACT: Tabulate corals are sometimes associated with other organisms occurring within their skeletons. These tabulate
endobionts are common in Lower Palaeozoic (Ordovician and Silurian) and Devonian strata, but until now they
have not been recognized in strata younger than early Frasnian. Here we report ?Chaetosalpinx sp. occurring
within the skeletons of the tabulate coral Yavorskia sp. (Favositida, Cleistoporidae) from the latest Famennian
("Strunian") in the Etroeungt area (Northern France). It can be stated that these endobionts survived the Frasnian-Famennian boundary crisis and recovered in the Late Famennian.
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New data on the stratigraphy of the folded Miocene Zone at the front of the Ukrainian Outer Carpathians
ANDREYEVA-GRIGOROVICH A.S.1, OSZCZYPKO N.2, SLACZKA A.2, OSZCZYPKO-CLOWES M.2, SAVITSKAYA N.3, TROFIMOVICZ N.3
1Institute of Geological Sciences NAS Ukraine, O. Gonchara 55b, Kiyev, Ukraine.
aida_grigorovich@mail.ru
2Institute of Geological Sciences, Jagiellonian University, Oleandry 2a, PL-30-063 Kraków, Poland.
nestor@geos.ing.uj.edu.pl
3Ukrainian State Geological Research Institute, Pasichna str. 38-a, UA-7900, Lviv, Ukraine.
trofym@yahoo.com
ABSTRACT: The litho- and biostratigraphy (calcareous nannofossils and foraminifera) were studied in several sections of the
foldedMiocene Zone (Boryslav-Pokuttya and Sambir nappes) of the Ukrainian Outer Carpathians. Based on new
biostratigraphic data, the age and correlation of the folded Miocene deposits in the marginal part of the Ukrainian
and Polish Outer Carpathians were established. The deposits studied range fromthe EarlyMiocene (Early Burdigalian
NN2 Zone) to the early LateMiocene (NN9 Zone). The facies and similarity in ages of the youngest deposits
of the folded Middle Miocene strata in Poland [Stebnyk (Sambir) Nappe and Zgłobice thrust-sheets] and
in Ukraine (Sambir Nappe) implies that they were folded at same time and that they represent a similar system
of tectonic units, developed in front of the advancing Carpathian orogen.
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Early Pliocene heteropods and pteropods (Mollusca, Gastropoda) from SantaMaria Island (Azores, Portugal): systematics and biostratigraphic implications
JANSSEN A.1, KROH A.2, AVILA S.P.3
1Nationaal Natuurhistorisch Museum Naturalis (Palaeontology Department), P.O. Box 9517, 2300 RA Leiden, The Netherlands; currently: 12, Triq tal'Hamrija, Xewkija XWK 9033, Gozo, Malta.
ariewjanssen@waldonet.net.mt
2Natural History Museum Vienna, Department of Geology & Palaeontology, Burgring 7, 1010 Vienna, Austria.
andreas.kroh@nhm-wien.ac.at
3MPB - Marine Palaeobiogeography Working Group of the University of the Azores, Departamento de Biologia, Universidade dos Açores, Rua da Mae de Deus, Apartado 1422, 9501 - 801 Ponta Delgada, Acores, Portugal; Centro do IMAR da Universidade dos Açores, 9901-862 Horta, Azores; Portugal.
avila@notes.uac.pt
ABSTRACT: Aholoplanktonic mollusc assemblage from Neogene sediments of theAzorean island SantaMaria is described and
analysed to determine the age of the sediments. Sixteen taxa are documented (three heteropods, thirteen pteropods),
fourteen of which are new records for the fossil fauna of SantaMaria Island. The composition of the heteropod and
pteropod assemblage indicates a Zanclean age, which contrasts with earlier age assignments to the Early,Middle or
LateMiocene based on benthicmolluscs, but is in good agreement withmore recent data based on foraminiferal and
geochemical evidence.
The pteropod Cavolinia marginata (BRONN, 1862) is re-described based on abundant topotypic material and a
neotype is designated. The species Cavolinia vendryesiana (GUPPY, 1873) is considered to be a junior subjective synonym
of C. marginata. The temporal range of the pteropod Limacina trochiformis (D'ORBIGNY, 1836) is extended
to the Zanclean.
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