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EN
Groundwater quality determination and age estimation in a desert landscape of El Golea province situated in the south of Algeria has been investigated in the present research paper. For this regard, 57 water samples were collected from an aquifer composed of two superimposed systems; phreatic and deep continental intercalary (CI) aquifers which are a part of the Northern Sahara Aquifer System (NWSAS). Samples were analyzed to assess the age and water quality using descriptive, multivariate statistics (PCA and HCA) and stable isotopes. It is revealed that more than 71% of the IC points are characterized by a water type (Ca2+, Mg2+) (HCO3 – )2 and more than 83% of the TC samples are defined by a water type (Ca2+, Na+) (HCO3 – , SO4 2 – ) and very high salt ions contents due to the influence of surface water, evaporate leaching and irrigation water return. The isotopic composition of samples of phreatic and CI aquifers shows a clear difference between the two qualities of water. The phreatic aquifer is characterized by the δ18O range from –4.68 to –6.1, whereas δ2H from –47.25 to –59.48 and CI with values of the δ18O range from –5.96 to –7.6, and δ2H range between –53.7 and –65.78 isotopic signature. The unconfined aquifer above IC forms a special case of a mixture of ancient water from deep horizons and recent water strongly enriched from shallow horizon lands.
EN
We document an upper upper Albian (Mortoniceras rostratum Zone) cephalopod assemblage from Clansayes (Drôme, south-eastern France). Although fossils are rare in local exposures and in the single sampled level, a decade of intensive fossil collecting yielded 290 ammonite and 5 nautilid specimens. In total, we describe 1 species of nautilid and 24 species (within 17 genera) of ammonites, including 13 heteromorphs. Only two of these ammonite taxa were previously recorded from the upper upper Albian at Clansayes, which demonstrates the value of this fauna with regard to taxonomy, palaeobiology and palaeobiogeography. Based on morphological and biometric analyses performed on an extensive material (104 specimens), we discriminate two species for the heteromorphic ammonite genus Mariella Nowak, 1916 within the Mortoniceras rostratum Zone. In addition, we investigate shell chirality patterns in Mariella from the late Albian of southern France. Upon comparison of the Clansayes material with older material from the immediately underlying upper Albian Mortoniceras fallax Zone at the neighbouring Salazac locality, we identify an increase in the proportion of sinistral specimens. This observed increase in the frequency of sinistral Mariella specimens may hypothetically be part of a global evolutionary pattern, considering that nearly all documented younger Cenomanian Mariella (and more generally Cenomanian turrilitids) are sinistral.
EN
Over 130 species are documented from the Upper Albian, Cenomanian and Upper Turonian Fahdène Formation and correlatives in Central Tunisia and northern Algeria, based on material described by Henri Coquand (1852, 1854, 1862, 1880), Léon Pervinquière (1907, 1910), Georges Dubourdieu (1953), Jacques Sornay (1955), and new collections. The material consists predominantly of limonitic nuclei, together with adults of micromorphs. There is no continuous record, and a series of faunas are recognised that can be correlated with the zonation developed in Western Europe. These are the Upper Albian Ostlingoceras puzosianum fauna, Lower Cenomanian Neostlingoceras carcitanense and Mariella (Mariella) harchaensis faunas, the upper Lower to lower Middle Cenomanian Turrilites scheuchzerianus fauna, Middle Cenomanian Calycoceras (Newboldiceras) asiaticum fauna, Upper Cenomanian Eucalycoceras pentagonum fauna, and the Upper Turonian Subprionocyclus neptuni fauna. Two new micromorph genera are described, Coquandiceras of the Mantelliceratinae and Cryptoturrilites of the Turrilitinae. Most of the taxa present have a cosmopolitan distribution, with a minority of Boreal, North American and endemic taxa.
EN
The Upper Greensand Formation, mostly capped by the Chalk, crops out on the edges of a broad, dissected plateau in Devon, west Dorset and south Somerset and has an almost continuous outcrop that runs from the Isle of Purbeck to the Vale of Wardour in south Wiltshire. The Formation is well exposed in cliffs in east Devon and the Isle of Purbeck, but is poorly exposed inland. It comprises sandstones and calcarenites with laterally and stratigraphically variable amounts of carbonate cement, glauconite and chert. The sedimentology and palaeontology indicate deposition in marginal marine-shelf environments that were at times subject to strong tidal and wave-generated currents. The formation of the Upper Greensand successions in the region was influenced by penecontemporaneous movements on major fault zones, some of which are sited over E-W trending Variscan thrusts in the basement rocks and, locally, on minor faults. Comparison of the principal sedimentary breaks in the succession with the sequence boundaries derived from world-wide sea-level curves suggests that local tectonic events mask the effects of any eustatic changes in sea level. The preserved fauna is unevenly distributed, both laterally and stratigraphically. Bivalves, gastropods and echinoids are common at some horizons but are not age-diagnostic. Ammonites are common at a few stratigraphically narrowly defined horizons, but are rare or absent throughout most of the succession. As a result, the age of parts of the succession is still poorly known.
EN
Brachauchenine pliosaurids were a cosmopolitan clade of macropredatory plesiosaurs that are considered to represent the only pliosaurid lineage that survived the faunal turnover of marine amniotes during the Jurassic–Cretaceous transition. However, the European record of the Early to early Late Cretaceous brachauchenines is largely limited to isolated tooth crowns, most of which have been attributed to the classic Cretaceous taxon Polyptychodon. Nevertheless, the original material of P. interruptus, the type species of Polyptychodon, was recently reappraised and found undiagnostic. Here, we describe a collection of twelve pliosaurid teeth from the upper Albian–middle Cenomanian interval of the condensed, phosphorite-bearing Cretaceous succession at Annopol, Poland. Eleven of the studied tooth crowns, from the Albian and Cenomanian strata, fall within the range of the morphological variability observed in the original material of P. interruptus from the Cretaceous of England. One tooth crown from the middle Cenomanian is characterized by a gently subtrihedral cross-section. Similar morphology has so far been described only for pliosaurid teeth from the Late Jurassic and Early Cretaceous. Even though it remains impossible to precisely settle the taxonomic distinctions, the studied material is considered to be taxonomically heterogeneous.
EN
The Aucellina biostratigraphy of the Upper Albian Kirchrode Marls Member succession in the Kirchrode I (1/91) cored borehole is described and the fauna illustrated. The borehole commenced at an unknown depth below the Early Cenomanian marls of the Bemerode Member, but higher beds of the Kirchrode Marls and the basal beds of the Bemerode Member were exposed in the Mittellandkanal and its Stichkanal extension at Misburg. The borehole and surface exposures permit a virtually complete Late Albian succession of Aucellina species to be observed. Published Aucellina range data from the borehole are reassessed and it is suggested that the lower part of the recorded range is based partly on misidentifications of fragments of thin-shelled bivalves such as Syncyclonema and Amussium. Aucellina appears in the borehole succession within the upper part of the Callihoplites auritus ammonite Subzone (Mortoniceras inflatum Zone) and continues to the top of the borehole succession within the Preaeschloenbachia briacensis ammonite Subzone (Stoliczkaia spp. Zone). Aucellina from higher in the briacensis Subzone collected from the Misburg Mittellandkanal section are also discussed and illustrated. There is some evidence that Aucellina occurs typically at levels in the borehole containing predominantly Boreal European Province ammonites, supporting the general inference that Aucellina lived in cooler northern waters. In contrast, Aucellina is poorly represented in intervals with Tethyan ammonites and thin-shelled inoceramids (e.g. the Mortoniceras (Durnovarites) perinflatum Subzone, Stoliczkaia spp. Zone). The briacensis Subzone, with an admixture of Tethyan (Stoliczkaia) and Boreal ammonites contains a distinctive, taxonomically highly diverse Aucellina assemblage. Relevant taxonomic research on European Late Albian and Early Cenomanian Aucellina faunas is reviewed. The Late Albian Aucellina succession in the borehole differs from that established from partially correlative successions in England.
EN
The present paper discusses foraminiferal assemblages and biozones established on the basis of studies of samples from ten borehole sequences of the Khanty-Mansiysk Horizon in the Samotlor area of the northern palaeobiogeographical district of western Siberia (Russia). In this region, middle and late Albian foraminiferal assemblages were first distinguished in western Siberia. Levels from which these assemblages have been recovered, are here referred to the following foraminiferal zones, the Ammobaculites fragmentarius–Gaudryinopsis filiformis Zone (middle Albian) and the Ammotium braunsteini–Verneuilinoides borealis assanoviensis Zone (upper Albian). Zonal assemblages are dominated by representatives of the orders Ammodiscida, Textulariida and Ataxophragmiida. Species of the ataxophragmiid genera Verneuilinoides, Pseudoverneuilina and Gaudryinopsis are the most characteristic, inclusive of several key index forms. Foraminiferal tests consist of agglutinated quartz-silica, the wall microstructure being almost exclusively medium and coarse grained. In specific composition, the Albian assemblages from the Samotlor area are similar to those from Transuralia (Russia) and to the Canadian Province, which, together with West-Siberian Province, forms the Arctic palaeobiogeographical realm.
EN
A previously unrecorded ammonite assemblage, comprising Lepthoplites sp., Callihoplites tetragonus (Seeley, 1865), C. cf. tetragonus, Arrhaphoceras cf. substuderi Spath, 1923, Cantabrigites sp., Stoliczkaiella (Stoliczkaiella) sp., Hamites cf. duplicatus Pictet and Campiche, 1861, H. cf. subvirgulatus Spath, 1941, and H. cf. venetzianus Pictet, 1847, is described from the mid-Cretaceous condensed succession at Annopol, Poland. These specimens are preserved as pale phosphates or sandstone moulds in a bed of reworked phosphatic nodules near the top of the Albian. This assemblage has many species in common with the late late Albian faunas from condensed deposits of England, Switzerland, and France. The presence of Callihoplites tetragonus indicates the lowermost upper upper Albian Mortoniceras fallax Zone. The ammonites studied are the youngest elements in the phosphate bed, which also contains taxa as old as the middle Albian Hoplites dentatus Zone. This bed originated through condensation and reworking of nodules and fossils in a period of low net sedimentation rate, being probably a reflection of a sea-level drop at the boundary between the classic ammonite zones of Mortoniceras inflatum and Stoliczkaiella dispar.
9
Content available Albian ammonites from northern Pakistan
EN
The occurrence of rich Albian ammonite faunas in what is now northern Pakistan has been known for more than 80 years, but there has been no comprehensive account of the assemblages present. A total of 36 taxa are described below. The middle part of the Lumshiwal Formation yields Upper Aptian ammonites south of the Samana Range. Elsewhere, it yields Douvilleiceras leightonense Casey, 1962, of the lower Lower Albian Leymeriella regularis Zone and the Sonneratia perinflata and S. kitchini Subzones of the Sonneratia chalensis Zone of the northwest European sequence. The top one to two metres of the Lumshiwal yields an abundant fauna of rolled and phosphatised ammonites that includes elements from much of the Albian. Of these, Prolyelliceras gevreyi (Jacob, 1907) first appears in the lower Lower Albian Leymeriella tardefurcata Zone. The commonest ammonite is Douvilleiceras mammillatum (Schlotheim, 1813) sensu lato, which ranges from the perinflata Subzone of the chalensis Zone to the Otohoplites bulliensis Subzone of the O. auritiformis Zone of the Lower Albian. The presence of Lyelliceras pseudolyelli (Parona and Bonarelli, 1897) indicates the uppermost, pseudolyelli Subzone of the auritiformis Zone. The presence of Lyelliceras lyelli (d’Orbigny, 1841) indicates the basal Middle Albian lyelli Subzone of the Hoplites dentatus Zone. There is no evidence for the higher parts of the Middle Albian. Dipoloceras (Rhytidoceras ) sp. indicates the presence of lower Upper Albian, possibly the pricei Zone. There is evidence, in the form of specifically indeterminate Mortoniceras (Mortoniceras) sp., of a level within the inflatum to fallax Zone inteval from a single locality, but no evidence of the succeeding parts of the upper Upper Albian. The base of the Kawagarth Formation that succeeds the Lumshiwal yields lower Upper Albian Mortoniceras (M.) geometricum Spath, 1932 of the Mortoniceras pricei Zone, northwest of Darmasand in the Samana range.
EN
Ammonites Mortoniceras (Subschloenbachia) sp. are preserved as attachment scars on the oyster shells from the topmost portion of the Albian succession at Annopol, Poland. These oyster-bioimmured ammonites show a closest affinity to the representatives of Mortoniceras (Subschloenbachia) characteristic of the upper Upper Albian Mortoniceras perinflatum Zone. No ammonites indicative of the uppermost Albian–lowermost Cenomanian Praeschloenbachia briacensis Zone are recorded. Thus, the hiatus at the Albian–Cenomanian boundary at Annopol embraces the latter zone. The presence (and dominance) of Mortoniceras in the upper Upper Albian ammonite assemblage of Annopol suggests that the representatives of this Tethyan genus could migrate into the epicratonic areas of Poland directly from the Tethyan Realm, via the Lwów (Lviv) region.
EN
The foraminiferal and radiolarian biostratigraphy of selected sections of the Zabijak Formation, the youngest sediments of the Tatra massif (Central Western Carpathians), have been studied. Benthic foraminifers, mainly agglutinated species, occur abundantly and continuously throughout the studied succession, while planktic foraminifers are generally sparse. Five planktic and two benthic foraminiferal zones have been recognized. The marly part of the Zabijak Formation comprises the Pseudothalmanninella ticinensis (Upper Albian) through the Rotalipora cushmani (Upper Cenomanian) planktic foraminiferal zones, and the Haplophragmoides nonioninoides and Bulbobaculites problematicus benthic foraminiferal zones. The radiolarians were recognized exclusively in the Lower Cenomanian part of the formation.
EN
Peculiarly shaped, relatively large (up to 30 cm in diameter) concretions of quartzitic sandstone occur in a single horizon of Upper Albian loose sands in the Cracow Upland, southern Poland. They are characterized by hollow interiors adorned with mass-aggregated moulds of the borings of diverse sponges, polychaetes and bivalves. These moulds represent the siliceous filling of borings in limestone clasts that had been subject to dissolution, leaving a hollow within the concretion that had formed around them. Synsedimentary block-faulting and jointing affected the Jurassic limestone-basement, causing the uplift of a local horst (the Glanow Horst), to within the littoral zone so that it became exposed to abrasion. It is inferred that a hurricane or catastrophic storm surge swept limestone debris fallen from the cliff out to the sandy offshore, where nucleation of soluble silica was presumably favoured by the decay of the soft tissue of live or dead rock-borers. After filling the emptyo borings and solution of the limestone clasts, the nucleation progressed intensely, finally completed by precipitation of siliceous sinter in the hollow interiors of some of the concretions during subsequent diagenesis and/or epigenesis.
EN
The macrofaunal content of an exceptionally fossiliferous Late Albian core section is described from Zippelsforde in the Brandenburg district in eastern Germany. The main faunal horizon includes among others Euhoplites vulgaris, Mortoniceras (Deiradoceras) albense, Neohibolites minimus, Inoceramus cf. anglicus and Actinoceramus sulcatus. This assemblage indicates a Hysteroceras varicosum Zone, Hysteroceras orbignyi Subzone age. That interval is known from the Anglo-Paris as well as from the Lower Saxony Basin in western Germany, but not was previously recorded from the North East German Basin. Therefore, the record fills a palaeogeographical gap between the Albian in the Carpathians and that of Central Europe. The superjacent interval contains Aucellina gryphaeoides, dating it as latest Albian (Mortoniceras (M.) inflatum Zone, late C. auritus Subzone or younger), and thus indicating a significant condensation within the Late Albian.
14
Content available remote The Upper Albian ammonite succession in the Montlaux section, Hautes-Alpes, France
EN
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.
EN
In the Klape Unit of the Pieniny Klippen Belt the Albian conglomerates with clasts of exotic carbonates, clastic sediments and also volcanic and plutonic rocks are relatively widespread. In the small area near the town Povażska Bystrica also scarce blueschist clasts of variegated petrographic types have been found. Three groups of starting rocks can be discerned for blueschists: pelagic sediments, metamorphic rocks (amphibolites, gneisses) and volcanic rocks. Based on immobile trace element (HFSE, REE) distribution two petrogenetic types of volcanic rocks have been identified: basalts with BABB signature and calc-alkaline basaltic andesites to rhyolites. Source of these rocks was probably a nappe stack located in the Carpathian interior and created in the Late Jurassic time as a result of subduction of the oceanic crust and adjacent volcanic arc and followed by collision during the Meliata Ocean closure
PL
Albskie zlepieńce jednostki klapskiej pienińskiego pasa skałkowego zawierające egzotyki skał węglanowych, klastycznych, jak również wulkanicznych i plutonicznych są szeroko rozprzestrzenione. Na małym obszarze w okolicy Povażskiej Bystricy (Słowacja zachodnia) w kilku stanowiskach znaleziono rzadkie egzotyki zróżnicowanych petrograficznie łupków glaukofanowych. Wyróżniono trzy grupy pierwotnych utworów przekształconych w te łupki: osady pelagiczne, skały metamorficzne (amfibolity, gnejsy) i skały wulkaniczne. W oparciu o niestabilne pierwiastki śladowe (HFSE, REE) zidentyfikowano dwa typy petrogenetyczne skał wulkanicznych: bazalty o cechach bazaltów obszarów zaułkowych (BABB) oraz wapniowo-alkaliczne andezyty i ryolity bazaltowe. Obszarem źródłowym tych skał były prawdopodobnie spłaszczowinowane jednostki zlokalizowane w obrębie Karpat wewnętrznych, powstałe w późnej jurze jako rezultat subdukcji skorupy oceanicznej i utworzonego w związku z tym łuku wulkanicznego, w następstwie kolizji podczas zamykania się oceanu Meliaty
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