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Bulletin of Geosciences

Rodríguez-Tovar FJ, Reolid M; Vol. 88, issue 4, pages 697 - 712A geochemical analysis has been conducted in the Fuente de la Vidriera section of the External Subbetic (Betic Cordillera, southern Spain) in order to interpret the incidence of the Toarcian Oceanic Anoxic Event (T-OAE) in the westernmost end of the Tethys. The obtained values of detrital, redox and palaeoproductivity proxies throughout the succession show minor fluctuations, but only punctual significant changes. Detrital input is nearly constant during the studied interval, except punctually in the lower part of serpentinum Zone, characterized by an increase in both fluvial and eolian detrital transport. Associated to this local higher fluvial and eolian activity, a comparatively higher concentration of organic matter is punctually registered, as revealed by the comparatively highest total organic carbon (TOC) value (0.99 wt.%). The remaining part of the section shows TOC values in the lower range of those registered in the Tethyan Toarcian sections (< 0.4 wt.%). The obtained ratios of redox-sensitive trace metals lead to the interpretation of oxic to dysoxic bottom-waters, with a singular sharp decrease in oxygenation corresponding to a short interval within the serpentinum Zone (sample FV-18) correlated to the T-OAE. The minor incidence of the T-OAE registered in this westernmost end of the Tethys, in which punctual dysoxic conditions are restricted only to a decimetre-scale interval reveals the importance of regional context and local oceanic-atmosphere dynamics on the local record of this phenomenon.

http://www.geology.cz/bulletin/contents/art1397 2013/11/02 - 08:03

Van Iten H, Muir LA, Botting JP, Zhang YD, Lin JP; Vol. 88, issue 4, pages 713 - 722Conulariella sp. and possibly one other conulariid species occur in close association with Sphenothallus sp. in the lower part of the early Floian Tonggao Formation near the town of Sandu, Guizhou Province, China. This is the only known occurrence of Conulariella in Early Ordovician rocks outside of Bohemia (Perunican terrane), and also the first report of Sphenothallus from the Ordovician of China. The apertural margin of Conulariella appears to have been mostly straight, and apertural lappets probably were not present in this genus. Some Tonggao conulariids may have attached to orbiculoid brachiopods in life. Based on the most recent palaeogeographical reconstructions of Gondwana and associated terranes, Conulariella could have had a dispersal path along the Gondwanan margin.

http://www.geology.cz/bulletin/contents/art1400 2013/11/02 - 08:03

Schulbert C, Nützel A; Vol. 88, issue 4, pages 723 - 778A rich gastropod fauna is decribed from the Early/Middle Jurassic boundary (late Toarcian/early Aalenian) of Franconia (N Bavaria, South Germany). It comprises 35 nominate species and additional 9 species are treated in open nomenclature. With a few exceptions, the studied material comes from the Jurensismergel and the Opalinuston formations of the Mistelgau clay pit near Bayreuth. These sediments represent marine soft bottom environments. Gastropods are the most diverse and the most abundant group of the benthic communities in the Mistelgau clay pit. Bivalves, ophiurid and crinoid ossicles as well as foraminifera are also abundant. Among the bivalves, the paper pecten Bositra buchi and the inoceramid Pseudomytiloides dubium are especially abundant. Most of the members of the benthic fauna are small (< 15 mm) or even minute. Only the bivalve Pseudomytiloides dubium, some of the vetigastropods (e.g., Pleurotomarioidea) and the family Gordenellidae (Turritelloidea and Proacirsa) attain a size larger than 2 cm. However, these large species are rare. The most abundant gastropods are the caenogastropod species Coelodiscus minutus and Toarctocera subpunctata. Both species are especially abundant in the lowermost portions of the sampled section. Towards the Aalenian, an increase in diversity can be observed. This reflects recovery from the late Pliensbachian/early Toarcian extinction event. This event was connected with early Toarcian anoxia in Central and Northern Europe including black shale deposition (Posidonienschiefer). The studied gastropod fauna lived during still impoverished but improving environmental conditions. The relatively high diversity and abundance of the benthos suggest aerobic or dysaerobic conditions, however with possible fluctuations of oxygen concentrations. The fauna was also constrained by soft bottom conditions. 12 species are described as new: Mistelgauia monarii, Hummelgauia microstriata, Jurilda zapfi Schulbert, Nützel & Gründel sp. nov., Franconicilda juliae, Carinathilda? dieneri, Conusella convexa, Cossmannina eggmaieri, Sinuarbullina? mistelgauensis, Striactaeonina waltschewi Schulbert, Nützel & Gründel sp. nov., Striactaeonina richterorum Schulbert, Nützel & Gründel sp. nov., Parvulactaeon imprimum Schulbert, Nützel & Gründel sp. nov. and Parvulactaeon inclinatum Schulbert, Nützel & Gründel sp. nov. Three genera are described as new: Hummelgauia, Mistelgauia and Franconicilda. The family Coelodiscidae Gründel&Nützel fam. nov. is described as new based on the probably holoplanktonic gastropod genus Coelodiscus.

http://www.geology.cz/bulletin/contents/art1418 2013/11/02 - 08:03

Haug JT, Leipner A, Wappler T, Haug C; Vol. 88, issue 4, pages 779 - 791We report fragmentary specimens from the Piesberg quarry (Upper Carboniferous, Northwestern Germany) that represent exuviae of nymphal blattoids (Dictyoptera). Most of the remains are isolated abdomina, one specimen also preserves a wing pad. The specimens document two developmental stages and include the smallest Palaeozoic blattoid nymph found to date. The specimens from the Piesberg quarry closely resemble other Palaeozoic blattoid nymphs, for example, specimens from the famous Mazon Creek Lagerstätte (Upper Carboniferous, Illinois, USA), at least as far as external morphology is concerned. As for preservation, the specimens from the Piesberg quarry show strong resemblance to specimens from the Lower Permian Elmo Lagerstätte (Kansas and Oklahoma, USA). The two Lagerstätten, although differing in age, appear therefore to be interesting candidates for a palaeoecological comparison. The find of immature insects at the Piesberg quarry is another example of fossilised development in arthropods from this Lagerstätte, other examples are known from Euproops, Arthropleura and Aphantomartus pustulatus

http://www.geology.cz/bulletin/contents/art1401 2013/11/02 - 08:03

Frank J, Wilmsen M, Košťák M; Vol. 88, issue 4, pages 793 - 812The endemic Late Cretaceous nautilid genus Deltocymatoceras Kummel, 1956 is represented by Deltocymatoceras leiotropis (Schlüter, 1876) and D. rugatum (Fritsch Schlönbach, 1872). Characteristic for this genus is a bulbous involute shell with strong radial ribbing and a ventral keel, which appears in post-juvenile ontogenetic stages. The combination of these morphological features is unique among post-Palaeozoic nautiloids. Both species are restricted to the Late Turonian–Middle Coniacian of Central Europe and England. Until now, the type species D. leiotropis was known based only on the holotype specimen. This specimen is re-described with revised occurrence and for the first time photographically illustrated. The only preserved syntype from the type specimens of D. rugatum was re-discovered during this revision and more than thirty other specimens were studied. Representatives of Deltocymatoceras show clear morphological changes during their ontogeny and acquisition of maturity, most notably the appearance of a ventral keel in premature stages and its disappearance at maturity. The hypothesis of a close phylogenetic affinity of Deltocymatoceras to the genus Cymatoceras Hyatt, 1884 is based on similar morphological features such as the suture, ribbing, shell shape and early ontogenetic development. The ventral keel is quite an exceptional feature of morphology in post-Palaeozoic nautiloids. In particular the combination with an involute depressed shell is only shared with representatives of the genus Angulithes Montfort, 1808 (Cretaceous–Palaeogene) and Gryponautilus Mojsisovic, 1902 (Triassic). The combination with a compressed and evolute planispiral shell is more common in Palaeozoic and some post-Palaeozoic nautiloids. The ventral keel is discussed here in relation to its functional aspects (hydrodynamic stability) in combination with the strong radial ribbing (protection of the shell against mechanical damage). The appearance of the genus concurred with the late Turonian shallowing/cooling associated with the “Hyphantoceras Event” and the availability of an ecologic niche (i.e., absence of medium-sized, keeled ammonites at that time). Low abundance, an endemic occurrence, and the very short stratigraphic range of the genus (~3.5 Ma) reflect the limited evolutionary success of the Deltocymatoceras lineage.

http://www.geology.cz/bulletin/contents/art1402 2013/11/02 - 08:03

Reyes-Abril J, Villas E, Gutiérrez-Marco JC, Jiménez-Sánchez A, Colmenar J; Vol. 88, issue 4, pages 813 - 828The family Harknessellidae Bancroft, 1928 (Orthida, Dalmanellidina) was designed to embrace an assemblage of species referred previously to Harknessella Reed, 1917, and included five genera known mainly from the Middle and Upper Ordovician of England. Herein, we suggest reassigning to this family the genus Cacemia Mitchell, 1974, widespread in the middle Darriwilian (upper Middle Ordovician) of the Iberian and Armorican massifs. Since its designation, Cacemia was placed among the dalmanellidin heterorthids, in spite of its strongly mucronate hinge line, which is totally unknown within this Mediterranean family. A new harknessellid has been identified from the upper Darriwilian beds of the Central Iberian Zone (Central Spain): Isabelella fascicostellata Reyes-Abril   Villas gen. et sp. nov. It is similar to Horderleyella Bancroft, 1928 for its coarsely fascicostellate radial ornamentation and obtuse cardinal angles, although its convexoplane to convexoconcave profile allows discrimination from the typically dorsibiconvex Horderleyella. A phylogenetic analysis of the family places both Cacemia and Isabelella in basal positions of their clades, which fits with their early stratigraphic record. Based on our study, the family Harknessellidae appears to have originated in the high latitude Mediterranean margins of Gondwana during pre-Darriwilian times, before the detachment of Avalonia from Gondwana. The family reached its highest diversification in Avalonia throughout the Late Ordovician, keeping connections with the Mediterranean and Proto-Andean margins of Gondwana, as well as with the mid-latitude palaeocontinents of Baltica and South China.

http://www.geology.cz/bulletin/contents/art1433 2013/11/02 - 08:03

Kvaček J; Vol. 88, issue 4, pages 829 - 836Pinus landsbergensis J. Kvaček sp. nov. is described from the Bohemian Cretaceous Basin (Czech Republic). The material comes from localities Lanšperk and Pecínov. It shows characteristic fascicles of five needles born on a dwarf shoot. Its epidermis is built of elongate rectangular ordinary cells and monocyclic stomata forming rows. Similar Pinus species from the Cretaceous of USA and Japan are discussed. A conspiceous similarity is recorded between P. landsbergensis and P. quinquefolia from the Late Cretaceous of USA. P. landsbergensis is also compared to recent species of the subgenus Pinus. The most similar in epidermal characters are Central American pines P. montezumae and P. devonensis.

http://www.geology.cz/bulletin/contents/art1444 2013/11/02 - 08:03

Zatoń M, Hara U, Taylor PD, Krobicki M; Vol. 88, issue 4, pages 837 - 863The specimen-rich and diverse bryozoan fauna from the Callovian hardground at Zalas Quarry in southern Poland is described. Twenty-two taxa of cyclostomes are recorded, of which three species are proposed as new: Microeciella calloviana, Reptomultisparsa viskovae and Mesonopora walteri. Due to preservational problems and an insufficient number of fertile colonies, species-level determination of fourteen forms was not possible. The most common bryozoans present are sheet-like bereniciform colonies, with uniserial runners and oligoserial ribbons less abundant. The number of the Callovian taxa present in the Zalas Quarry is very similar to the Upper Bathonian-Lower Callovian bryozoan assemblage from the classic locality of Balin in southern Poland. Taking the strictly Callovian age into account, the Zalas assemblage is the most diverse for that age ever noted.

http://www.geology.cz/bulletin/contents/art1466 2013/11/02 - 08:03

Maillet S, Dojen C, Milhau B ; Vol. 88, issue 4, pages 865 - 892Bed-by-bed sampling of three sections (Flohimont, Cul d’Houille and Nichet) exposing almost the entire Fromelennes Formation (Devonian, Middle and Late Givetian) in the historical type-area of the Givetian (Givet, Ardennes Department, France) provided more than 12,000 benthic ostracods. A high ostracod biodiversity is reported in these sections; 113 taxa are recognized of which 2 species are new: Acratia lucea sp. nov. and Orthocypris? cristae sp. nov. The stratigraphical distribution of the ostracods shows the installation of a Givetian fauna close to the base of the Fromelennes Formation with many endemic taxa and its disappearance as well as its subsequent replacement with more cosmopolitan taxa at the top of the formation with Frasnian affinities. This distribution is closely related to the major events of the Middle and Late Givetian in the Ardennes: the transgression pulse at the top of the Mont d’Haurs Formation, the global Taghanic Biocrisis and the global Givetian/Frasnian sea level rise. Climate change at the end of the Givetian possibly amplifies the effects of the sea level rise. The pattern of disappearance of many ostracod taxa in the Middle Givetian and their replacement by a new fauna as early as the Late Givetian is at least a supraregional phenomenon. Orthocypris? cristae sp. nov., Kielciella arduennensis Adamczak & Coen, 1992, Jefina kaisini Coen, 1985 and Cavellina rhenana Krommelbein, 1954 are considered as regional to supraregional stratigraphic markers. We establish the presence of a Middle Givetian ostracod province on the Givetian carbonate platform.

http://www.geology.cz/bulletin/contents/art1424 2013/11/02 - 08:03

Jirásek J, Sedláčková L, Sivek M, Martínek K, Jureczka J; Vol. 88, issue 4, pages 893 - 914The Castle Conglomerate Unit in the Poruba Member (Early Namurian, Mississippian) is a lithosome composed of coarse-grained sandstones and conglomerates. Its thickness, lithology and extensive area make it unique in the paralic sequence of the Ostrava Formation of the Upper Silesian Basin. The unit was studied on the basis of information from exploratory boreholes, mines and its outcrop at the type locality in the Lučina Valley in Silesian Ostrava. Locally, the unit attains a thickness of up to 115 m (average 24.4 m). Its present-day area is approximately 992 km2. The axis of the conglomerate facies (with character of interbeds) in the unit has a NNE-SSW alignment and coincides with the axis of the basin’s maximum subsidence during the sedimentation of the Poruba Member. The maximum aggregate thickness of the conglomerate facies is 60 m; their present-day area of occurrence is approximately 480 km2. The Castle Conglomerate Unit represents deposits of a low-sinuosity river system. The upper part of the multistorey channel fill is characterised by channels filled with sand bedforms and occasional bars. Palaeocurrents show a low spread of vectors, primarily to the NNW. The lower part does not crop out; it is known, therefore, only from boreholes. The presence of the unit’s coarse-grained clastics inside the basin filling, which is dominated by siltstone and medium-grained sandstone, indicates a major drop in the base level, which is interpreted here as a drop in the sea level. We correlate this event with the major glacio-eustatic sea level drop at 323 Ma that can be connected with the onset of glaciation interval C2 of the Late Paleozoic Ice Age. Because the resolution of available stratigraphic and geochronologic data is not currently sufficient, an alternative explanation of the tectonic origin cannot be ruled out of the discussion and may also be valid in regard to the active Variscan foreland.

http://www.geology.cz/bulletin/contents/art1364 2013/11/02 - 08:03

LeHerisse A, Paris F, Steemans P; Vol. 88, issue 3, pages 483 - 504Well preserved assemblages of cryptospores, chitinozoans, acritarchs, leiospheres, tasmanitids, colonies of Gloeocapsomorpha, scolecodonts and eurypterid fragments from 23 core samples of the Moussegouda core hole in the Erdi Basin, northern Chad, and from two samples from well KW-2 in Kufra Basin, South East Libya are investigated. These palynomorphs were recovered from the southernmost North African marine deposits of Late Ordovician and possibly early Silurian age. The palaeoenvironment evolves from late Hirnantian glacio-marine diamictites to silt-dominated sequences suggesting a marginal marine environment of possibly latest Hirnantian to earliest Rhuddanian age (post-elongata-pre-fragilis chitinozoan assemblages). The recovered palynomorph assemblages are compared and correlated with contemporaneous assemblages recorded in other northern Gondwana localities (Mauritania, Morocco Algeria, Libya, Africa, Saudi Arabia, Jordan), and in South Africa, in order to evaluate possible effects of the ice cap melting on palynomorph assemblages and sedimentation. Our goal is also to improve the regional biostratigraphy across the Ordovician-Silurian boundary. The composition of the recovered palynomorph assemblages, with mixed terrestrial and marine microflora, suggests that the topmost Ordovician or earliest Silurian in northern Chad and southeastern Libya, reflects nearshore conditions, with obvious fresh water influences. The lack of black shale or grey shale in the uppermost Ordovician and of “hot shale” in the lower Silurian in these areas, and their replacement by siltstones, are probably related to an isostatic readjustment that rapidly starved the marine sedimentation in the areas previously overlain by a thick ice cover during the climax of the Hirnantian glaciation. Tasmanites tzadiensis Le Herisse sp. nov. and Euconochitina moussegoudaensis Paris sp. nov., two new palynomorphs of biostratigraphical interest are described and illustrated.

http://www.geology.cz/bulletin/contents/art1383 2013/08/13 - 05:11

Kaim A, Nützel A, Hautmann M, Bucher H; Vol. 88, issue 3, pages 505 - 516Five gastropod species are described from the Early Triassic (Smithian, Spathian) of the Salt Range in Pakistan, which is the first detailed documentation of gastropods from this key area of the Palaeozoic-Mesozoic transition. Bellerophontoidea are represented by Warthia hisakatsui. Bellerophontoidea were widespread in the Paleozoic and had their last appearance in the early Smithian. Anisian and later reports of this group are discussed, but currently remain doubtful. Soleniscidae, a typical Late Palaeozoic caenogastropod family, are present with two new species: Strobeus batteni and S. pakistanensis. The neritimorph genus Naticopsis and the caenogastropod Coelostylina are present with one species each, provisionally treated in open nomenclature. Naticopsis? sp. shows preservation of original colour patterns, which is very rare in Early Triassic gastropods. All identified genera originated during the Paleozoic (perhaps with the exception of Coelostylina) and are thus survivors or holdovers. Warthia and Strobeus survived the end-Permian mass extinction but went extinct during the Smithian when environmental conditions deteriorated again.

http://www.geology.cz/bulletin/contents/art1395 2013/08/13 - 05:11

Hoffmann R, Iba Y, Kawabe F, Mutterlose J; Vol. 88, issue 3, pages 517 - 524Here, we describe for the first time the occurrence of well preserved Pictetia from the Albian of northeastern Japan (Miyako Group) and discuss the implications for the systematic assignment of the genus. A detailed systematic description of P. astieriana based on the newly collected material is given. Earlier systematic assignment to lytoceratids resulted from similar conch morphology and ornamentation. Based on the new knowledge of the development of the juvenile suture lines, Pictetia is tentatively assigned to the Hamitidae.

http://www.geology.cz/bulletin/contents/art1379 2013/08/13 - 05:11

Popov LE, Kebria-ee Zadeh M-R, Ghobadi Pour M, Holmer LE, Modzalevskaya TL; Vol. 88, issue 3, pages 525 - 538The Cambrian (Furongian) shallow water carbonates in the Mila Formation in the Tuyeh-Darvar area (eastern Alborz, northern Iran) contain numerous shell beds, entirely composed of disarticulated valves of the billingsellide brachiopods Billingsella? fortis sp. nov. and Hyrcanostrophia tuyehensis gen. et sp. nov. Higher up in the Mila Formation, the shallow water carbonates are replaced by nodular limestones, deposited in an open marine environment, containing Palaeostrophia tecta Nikitin & Popov, 1983 and the early polytoechioid Darvaretoechia prisca gen. et sp. nov. These two different brachiopod assemblages are assigned to the oligotaxic Billingsella and Palaeostrophia associations, respectively. These associations are considered to represent precursors to the brachiopod-dominated benthic assemblages of the Palaeozoic Evolutionary Fauna. The new brachiopod faunas from the Alborz Terrane are closely similar to contemporaneous Furongian faunas from the Australasian sector of Gondwana, in particular, to those from South China and the Kazakhstanian terranes.

http://www.geology.cz/bulletin/contents/art1393 2013/08/13 - 05:11

Bauer K, Kustatscher E, Krings M; Vol. 88, issue 3, pages 539 - 556Ginkgophyte foliage fossils (impressions and compressions lacking cuticle) from several of the historical Kupferschiefer localities in Germany have been re-studied using macromorphometry. Baiera digitata is by far the most common ginkgophyte in the Kupferschiefer, while other taxa are relatively rare.Anew taxon, for which the name Baiera mansfeldensis is proposed, differs from B. digitata in having a much thinner, curved petiole and a curved lamina, as well as a narrow basal angle. Esterella gracilis, a taxon previously known exclusively from France, is reported for the first time from Germany. The foliage genera Baiera and Sphenobaiera have a complicated taxonomic history, and the problematic contiguity that exists between the two taxa has lead to considerable confusion. It appears that the radiation of the ginkgophytes started well before the end-Permian mass-extinction, and that Permian ginkgophytes were more diverse than previously believed.

http://www.geology.cz/bulletin/contents/art1394 2013/08/13 - 05:11

Bauer K, Kustatscher E, Krings M; Vol. 88, issue 3, pages 539 - 556Ginkgophyte foliage fossils (impressions and compressions lacking cuticle) from several of the historical Kupferschiefer localities in Germany have been re-studied using macromorphometry. Baiera digitata is by far the most common ginkgophyte in the Kupferschiefer, while other taxa are relatively rare.Anew taxon, for which the name Baiera mansfeldensis is proposed, differs from B. digitata in having a much thinner, curved petiole and a curved lamina, as well as a narrow basal angle. Esterella gracilis, a taxon previously known exclusively from France, is reported for the first time from Germany. The foliage genera Baiera and Sphenobaiera have a complicated taxonomic history, and the problematic contiguity that exists between the two taxa has lead to considerable confusion. It appears that the radiation of the ginkgophytes started well before the end-Permian mass-extinction, and that Permian ginkgophytes were more diverse than previously believed.

http://www.geology.cz/bulletin/contents/art1394 2013/08/13 - 05:11

Matys Grygar T, Mach K; Vol. 88, issue 3, pages 557 - 571Six sediment cores from two of four depocentres in the Most Basin, mostly consisting of macrofossil barren fluviodeltaic and lacustrine sediments of Holešice and Libkovice members of the Most Formation (lower Miocene, Burdigalian) were subjected to chemostratigraphic correlation, based on CEC and EDXRF proxy element analyses. CEC-step, prominent K/Al minima and crandallite-bearing horizons in monotonous lacustrine mudstones of the Libkovice Member provide several local isochronous or nearly isochronous key horizons, which we propose for a basin-scale correlation of the upper Most Basin sediment fill. These key horizons prove a spatially uniform sedimentary environment in a single lake (original area ˜1,000 km2) during deposition of a considerable part of the siliciclastics overlying the main coal seam that tops the lower basin fill. We propose the CEC-step horizon as a novel boundary between Holešice and Libkovice members, i.e. the conversion of previously formal lithostratigraphic units to members with an isochronous boundary. That boundary together with recent sedimentological studies would assign Břešťany clay to the top of the Holešice Member. The upper boundary of the Libkovice Member could be the sediment coarsening related to a lake level decrease before deposition of Lom coal seam. The study will allow progress in palaeogeographic and palaeoenviromental reconstruction of the lower Miocene in the Most Basin. The proxy analyses (CEC vs Al/Si ratios) allow reliable numeric differentiation between kaolinite-rich, smectite-poor and smectite-rich clay assemblages in Holešice and Libkovice members. The plots of CEC vs Al/Si ratios should be applicable for fingerprinting any other monotonous lacustrine clastics with variable mineralogy of the clay assemblage.

http://www.geology.cz/bulletin/contents/art1372 2013/08/13 - 05:11

Matys Grygar T, Mach K; Vol. 88, issue 3, pages 557 - 571Six sediment cores from two of four depocentres in the Most Basin, mostly consisting of macrofossil barren fluviodeltaic and lacustrine sediments of Holešice and Libkovice members of the Most Formation (lower Miocene, Burdigalian) were subjected to chemostratigraphic correlation, based on CEC and EDXRF proxy element analyses. CEC-step, prominent K/Al minima and crandallite-bearing horizons in monotonous lacustrine mudstones of the Libkovice Member provide several local isochronous or nearly isochronous key horizons, which we propose for a basin-scale correlation of the upper Most Basin sediment fill. These key horizons prove a spatially uniform sedimentary environment in a single lake (original area ˜1,000 km2) during deposition of a considerable part of the siliciclastics overlying the main coal seam that tops the lower basin fill. We propose the CEC-step horizon as a novel boundary between Holešice and Libkovice members, i.e. the conversion of previously formal lithostratigraphic units to members with an isochronous boundary. That boundary together with recent sedimentological studies would assign Břešťany clay to the top of the Holešice Member. The upper boundary of the Libkovice Member could be the sediment coarsening related to a lake level decrease before deposition of Lom coal seam. The study will allow progress in palaeogeographic and palaeoenviromental reconstruction of the lower Miocene in the Most Basin. The proxy analyses (CEC vs Al/Si ratios) allow reliable numeric differentiation between kaolinite-rich, smectite-poor and smectite-rich clay assemblages in Holešice and Libkovice members. The plots of CEC vs Al/Si ratios should be applicable for fingerprinting any other monotonous lacustrine clastics with variable mineralogy of the clay assemblage.

http://www.geology.cz/bulletin/contents/art1372 2013/08/13 - 05:11

Bek J; Vol. 88, issue 3, pages 573 - 581Pennsylvanian microspinate/spinate mio- and microspores are formerly assigned to cingulate species of Lycospora (Schopf et al.), which were described by Potonie & Kremp. In the present paper, from the three existing species of distally microspinate miospores of this type [L. granulata Kosanke, L. orbicula (Potonie & Kremp) Smith & Butterworth and L. chaloneri Scott & Hemsley] two of them, L. orbicula and L. chaloneri are assigned to new pseudosaccate miospore genus Microspinosporites gen. nov. Miospores of this genus are characterized by inner body and distal and proximal microspinae/spinae, except for the contact area.Acingulum is not developed. The fructifications that produced Microspinosporites were bisporangiate cones of the genera Flemingites Carruthers and probably Moscvostrobus Naugolnykh & Orlova, and were born on arborescent lycopsids of the genus Paralycopodites (Moorey & Moorey) DiMichele. The morphology of Microspinosporites is similar to that of e.g., Geminospora (Balme) Playford and some other pseudosaccate miospore genera.

http://www.geology.cz/bulletin/contents/art1365 2013/08/13 - 05:11

Bek J; Vol. 88, issue 3, pages 573 - 581Pennsylvanian microspinate/spinate mio- and microspores are formerly assigned to cingulate species of Lycospora (Schopf et al.), which were described by Potonie & Kremp. In the present paper, from the three existing species of distally microspinate miospores of this type [L. granulata Kosanke, L. orbicula (Potonie & Kremp) Smith & Butterworth and L. chaloneri Scott & Hemsley] two of them, L. orbicula and L. chaloneri are assigned to new pseudosaccate miospore genus Microspinosporites gen. nov. Miospores of this genus are characterized by inner body and distal and proximal microspinae/spinae, except for the contact area.Acingulum is not developed. The fructifications that produced Microspinosporites were bisporangiate cones of the genera Flemingites Carruthers and probably Moscvostrobus Naugolnykh & Orlova, and were born on arborescent lycopsids of the genus Paralycopodites (Moorey & Moorey) DiMichele. The morphology of Microspinosporites is similar to that of e.g., Geminospora (Balme) Playford and some other pseudosaccate miospore genera.

http://www.geology.cz/bulletin/contents/art1365 2013/08/13 - 05:11

McKellar RC, Glasier JRN, Engel MS; Vol. 88, issue 3, pages 583 - 594A new genus and species are described within the ant subfamily Dolichoderinae (Formicidae). Chronomyrmex medicinehatensis gen. et sp. nov. McKellar, Glasier & Engel provides a solid example of Dolichoderinae within the Campanian Grassy Lake amber of southern Alberta (Late Cretaceous, 78–79 Ma). The new species fills a void in the dolichoderine fossil record left by Eotapinoma canadensis Dlussky, a putative dolichoderine whose taxonomic placement has been questioned, and whose type material has been lost. As such, C. medicinehatensis provides a constraint for divergence times of the subfamily and Leptomyrmecini, one of its recently resurrected tribes. This discovery greatly extends the proposed divergence time for Dolichoderinae, and likely Leptomyrmecini, to more than 78 Ma – contrary to some of the more recent estimates inferred from molecular phylogenies.

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McKellar RC, Glasier JRN, Engel MS; Vol. 88, issue 3, pages 583 - 594A new genus and species are described within the ant subfamily Dolichoderinae (Formicidae). Chronomyrmex medicinehatensis gen. et sp. nov. McKellar, Glasier & Engel provides a solid example of Dolichoderinae within the Campanian Grassy Lake amber of southern Alberta (Late Cretaceous, 78–79 Ma). The new species fills a void in the dolichoderine fossil record left by Eotapinoma canadensis Dlussky, a putative dolichoderine whose taxonomic placement has been questioned, and whose type material has been lost. As such, C. medicinehatensis provides a constraint for divergence times of the subfamily and Leptomyrmecini, one of its recently resurrected tribes. This discovery greatly extends the proposed divergence time for Dolichoderinae, and likely Leptomyrmecini, to more than 78 Ma – contrary to some of the more recent estimates inferred from molecular phylogenies.

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Su T, Spicer RA, Liu Y-S (C), Huang Y-J, Xing Y-W, Jacques FMB, Chen W-Y, Zhou Z-K; Vol. 88, issue 3, pages 595 - 608The relationship between leaf physiognomy and precipitation has been explored worldwide in regions under different climate conditions. Unlike the linear relationship established between the percentage of woody dicot species with entire margins and mean annual temperature, precipitation has been reported to correlate to different leaf physiognomic characters depending on the region where the correlation is studied. To investigate if precipitation can be calculated from leaf physiognomic characters on the basis of regional sample sites, data from 50 mesic to humid forests in China were analyzed in this study. With data from Chinese forests, the leaf-area analysis based on linear regression between natural logarithms of leaf size and mean annual precipitation (MAP) shows no significant correlation. Both single and multiple linear regression analyses fail to confirm the correlation between leaf physiognomy and precipitation, which may result from the similarity of modern spatial distribution of temperature and precipitation in China. Our results show that, due to variations in climatic conditions among sampling regions, leaf physiognomic characters that correlate to precipitation are not consistent worldwide, and applications of models without considering regional constraints could mislead our understanding of palaeoclimate. Therefore, when choosing a leaf physiognomic model for palaeoclimate reconstructions, it is important to determine if the leaf physiognomy of the palaeoflora lies within the leaf physiognomic spectrum of the model used.

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Su T, Spicer RA, Liu Y-S (C), Huang Y-J, Xing Y-W, Jacques FMB, Chen W-Y, Zhou Z-K; Vol. 88, issue 3, pages 595 - 608The relationship between leaf physiognomy and precipitation has been explored worldwide in regions under different climate conditions. Unlike the linear relationship established between the percentage of woody dicot species with entire margins and mean annual temperature, precipitation has been reported to correlate to different leaf physiognomic characters depending on the region where the correlation is studied. To investigate if precipitation can be calculated from leaf physiognomic characters on the basis of regional sample sites, data from 50 mesic to humid forests in China were analyzed in this study. With data from Chinese forests, the leaf-area analysis based on linear regression between natural logarithms of leaf size and mean annual precipitation (MAP) shows no significant correlation. Both single and multiple linear regression analyses fail to confirm the correlation between leaf physiognomy and precipitation, which may result from the similarity of modern spatial distribution of temperature and precipitation in China. Our results show that, due to variations in climatic conditions among sampling regions, leaf physiognomic characters that correlate to precipitation are not consistent worldwide, and applications of models without considering regional constraints could mislead our understanding of palaeoclimate. Therefore, when choosing a leaf physiognomic model for palaeoclimate reconstructions, it is important to determine if the leaf physiognomy of the palaeoflora lies within the leaf physiognomic spectrum of the model used.

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Carnevale G, Harzhauser M; Vol. 88, issue 3, pages 609 - 620Fishes of the subfamily Gaidropsarinae, commonly known as rocklings, are anatomically unique within the family Gadidae (Teleostei, Gadiformes), mostly because of their possession of a highly specialized chemosensory and vibratile first dorsal fin. The genus Gaidropsarus contains 13 extant species occurring from subtropical to temperate waters in the North Atlantic, Mediterranean, South Africa, New Zealand, Tasmania, Japan and southeastern Pacific, plus a single fossil species from the Miocene of Algeria. A new species of rockling, Gaidropsarus pilleri sp. nov., is described from the Middle Miocene (Late Badenian) corallinacean limestone of St. Margarethen in Burgenland, Eisenstadt-Sopron Basin, Austria based on seven articulated skeletons. The new species is based on a unique combination of features, including: possession of a wide neurocranium (neurocranial width contained less than two times in its length); well-developed sphenotic spine; epibranchials 2 and 3 characterized by massive uncinate processes; presence of 44 (13 + 31) vertebrae; five posterior parapophyses enlarged, the posterior three wing-like; 2nd dorsal fin contains about 50 rays; anal fin with 43 rays; caudal peduncle very short (2.4% SL). Gaidropsarus pilleri sp. nov. is the earliest known occurrence of the rocklings based on skeletal remains. The vibratile and chemosensory first dorsal fin of gaidropsarines may have arisen by co-option of the first dorsal-fin module.

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Carnevale G, Harzhauser M; Vol. 88, issue 3, pages 609 - 620Fishes of the subfamily Gaidropsarinae, commonly known as rocklings, are anatomically unique within the family Gadidae (Teleostei, Gadiformes), mostly because of their possession of a highly specialized chemosensory and vibratile first dorsal fin. The genus Gaidropsarus contains 13 extant species occurring from subtropical to temperate waters in the North Atlantic, Mediterranean, South Africa, New Zealand, Tasmania, Japan and southeastern Pacific, plus a single fossil species from the Miocene of Algeria. A new species of rockling, Gaidropsarus pilleri sp. nov., is described from the Middle Miocene (Late Badenian) corallinacean limestone of St. Margarethen in Burgenland, Eisenstadt-Sopron Basin, Austria based on seven articulated skeletons. The new species is based on a unique combination of features, including: possession of a wide neurocranium (neurocranial width contained less than two times in its length); well-developed sphenotic spine; epibranchials 2 and 3 characterized by massive uncinate processes; presence of 44 (13 + 31) vertebrae; five posterior parapophyses enlarged, the posterior three wing-like; 2nd dorsal fin contains about 50 rays; anal fin with 43 rays; caudal peduncle very short (2.4% SL). Gaidropsarus pilleri sp. nov. is the earliest known occurrence of the rocklings based on skeletal remains. The vibratile and chemosensory first dorsal fin of gaidropsarines may have arisen by co-option of the first dorsal-fin module.

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Okuyucu C, Vachard D, Göncüoğlu MC; Vol. 88, issue 3, pages 621 - 645The Cebeciköy Limestone from the Variscan flysch of the İstanbul Terrane is assigned to the foraminiferal MFZ11 zone (late early Viséan, formerly V2a). This zone is essentially the range zone of Uralodiscus rotundus. Additional bioevents are proposed for characterizing the upper part of this biozone (MFZ11B subzone): the LAD of Eoendothyranopsis and the FAD of Pararchaediscus and Conilidiscus. The majority of foraminifers and algae, belonging locally to MFZ11 are well-known, except for the following taxa: Issinella luteotubulifomis sp. nov., I. enormis sp. nov., Vicinesphaera parasqualida sp. nov., Planogloboendothyra modesta sp. nov. and Endothyra irinaeformis sp. nov. The İstanbul Terrane is connected with the southern branch of the Palaeotethys, whereas the Zonguldak Terrane is connected with the northern branch of this one.

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Okuyucu C, Vachard D, Göncüoğlu MC; Vol. 88, issue 3, pages 621 - 645The Cebeciköy Limestone from the Variscan flysch of the İstanbul Terrane is assigned to the foraminiferal MFZ11 zone (late early Viséan, formerly V2a). This zone is essentially the range zone of Uralodiscus rotundus. Additional bioevents are proposed for characterizing the upper part of this biozone (MFZ11B subzone): the LAD of Eoendothyranopsis and the FAD of Pararchaediscus and Conilidiscus. The majority of foraminifers and algae, belonging locally to MFZ11 are well-known, except for the following taxa: Issinella luteotubulifomis sp. nov., I. enormis sp. nov., Vicinesphaera parasqualida sp. nov., Planogloboendothyra modesta sp. nov. and Endothyra irinaeformis sp. nov. The İstanbul Terrane is connected with the southern branch of the Palaeotethys, whereas the Zonguldak Terrane is connected with the northern branch of this one.

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Wilmsen M, Nagm E; Vol. 88, issue 3, pages 647 - 674The Upper Cenomanian to Lower Turonian ammonoid fauna of the Saxonian Cretaceous (Elbtal Group, Saxony, Germany) has been revised based on the study of 270 specimens hosted in the Museum für Mineralogie und Geologie (MMG) of the Senckenberg Naturhistorische Sammlungen Dresden. In total, 12 species have been identified and, based on this revision, a number of ammonoids are now reported and/or illustrated for the first time from the Elbtal Group of Saxony: Euomphaloceras septemseriatum, Neocardioceras juddii barroisi, Watinoceras coloradoense, Spathites (Jeanrogericeras) reveliereanus, Sciponoceras gracile and Scaphites equalis. The study demonstrated the presence of all Upper Cenomanian and Lower Turonian standard ammonite biozones in the lithostratigraphic succession of the lower Elbtal Group: the lower Upper Cenomanian Calycoceras naviculare Zone (represented by the Oberhäslich Formation), the mid- and upper Upper Cenomanian Metoicoceras geslinianum and Neocardioceras juddii zones (represented by the Dölzschen Formation), and the Lower Turonian Watinoceras coloradoense and Mammites nodosoides zones (represented by the Brießnitz Formation). The ammonoid fauna from the Saxonian Cretaceous is dominated by strongly ornamented and widely distributed Acanthoceratidae.

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Wilmsen M, Nagm E; Vol. 88, issue 3, pages 647 - 674The Upper Cenomanian to Lower Turonian ammonoid fauna of the Saxonian Cretaceous (Elbtal Group, Saxony, Germany) has been revised based on the study of 270 specimens hosted in the Museum für Mineralogie und Geologie (MMG) of the Senckenberg Naturhistorische Sammlungen Dresden. In total, 12 species have been identified and, based on this revision, a number of ammonoids are now reported and/or illustrated for the first time from the Elbtal Group of Saxony: Euomphaloceras septemseriatum, Neocardioceras juddii barroisi, Watinoceras coloradoense, Spathites (Jeanrogericeras) reveliereanus, Sciponoceras gracile and Scaphites equalis. The study demonstrated the presence of all Upper Cenomanian and Lower Turonian standard ammonite biozones in the lithostratigraphic succession of the lower Elbtal Group: the lower Upper Cenomanian Calycoceras naviculare Zone (represented by the Oberhäslich Formation), the mid- and upper Upper Cenomanian Metoicoceras geslinianum and Neocardioceras juddii zones (represented by the Dölzschen Formation), and the Lower Turonian Watinoceras coloradoense and Mammites nodosoides zones (represented by the Brießnitz Formation). The ammonoid fauna from the Saxonian Cretaceous is dominated by strongly ornamented and widely distributed Acanthoceratidae.

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Sklenář J, Kočí T, Jäger M; Vol. 88, issue 3, pages 675 - 695The relatively rich sabellid and serpulid polychaete oryctocenoses of the hemipelagic Upper Turonian of the Bohemian Cretaceous Basin are hereby revised. Seven species from six genera were identified and described from the present key locality of Úpohlavy near Lovosice. Ongoing revision of previously published literature as well as the recently collected material resulted in eight polychaete species from seven genera being identified from the hemipelagic Late Turonian sediments of the basin: sabellids Glomerula plexus (J. de C. Sowerby), G. lombricus (Defrance) and serpulids Pyrgopolon (Septenaria) macropus (J. de C. Sowerby), Neovermilia ampullacea (J. de C. Sowerby), Dorsoserpula wegneri (Jäger), Serpula? (Cementula?) biplicata (Reuss), Josephella subanulata Regenhardt and Neomicrorbis crenatostriatus (Münster in Goldfuss) with the subspecies N. c. crenatostriatus. Data gained from the Úpohlavy quarry allows us not only to accomplish the revision presented here, but also deepen our knowledge of life strategies and paleoecology of the tubiculous polychaetes living in soft bottom conditions of a shallow, epicontinental sea. Among other findings the strong tendency towards a cryptic mode of life in Neovermilia ampullacea is discussed and an extraordinarily well preserved sample of Glomerula plexus reeflets network is documented. Two groups with different ecological amplitude have been recognised in the Úpohlavy polychaete communities.

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Sklenář J, Kočí T, Jäger M; Vol. 88, issue 3, pages 675 - 695The relatively rich sabellid and serpulid polychaete oryctocenoses of the hemipelagic Upper Turonian of the Bohemian Cretaceous Basin are hereby revised. Seven species from six genera were identified and described from the present key locality of Úpohlavy near Lovosice. Ongoing revision of previously published literature as well as the recently collected material resulted in eight polychaete species from seven genera being identified from the hemipelagic Late Turonian sediments of the basin: sabellids Glomerula plexus (J. de C. Sowerby), G. lombricus (Defrance) and serpulids Pyrgopolon (Septenaria) macropus (J. de C. Sowerby), Neovermilia ampullacea (J. de C. Sowerby), Dorsoserpula wegneri (Jäger), Serpula? (Cementula?) biplicata (Reuss), Josephella subanulata Regenhardt and Neomicrorbis crenatostriatus (Münster in Goldfuss) with the subspecies N. c. crenatostriatus. Data gained from the Úpohlavy quarry allows us not only to accomplish the revision presented here, but also deepen our knowledge of life strategies and paleoecology of the tubiculous polychaetes living in soft bottom conditions of a shallow, epicontinental sea. Among other findings the strong tendency towards a cryptic mode of life in Neovermilia ampullacea is discussed and an extraordinarily well preserved sample of Glomerula plexus reeflets network is documented. Two groups with different ecological amplitude have been recognised in the Úpohlavy polychaete communities.

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Loydell DK; Vol. 87, issue 4, pages 633 - 634

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Corradini C, Corriga MG; Vol. 87, issue 4, pages 635 - 650The main conodont zonation schemes for the Přídolí and the Lochkovian presents some problems that make difficult their use in several geographical areas. Data from several sections in Sardinia and the Carnic Alps not only allow to built a regional zonation scheme for these areas, but also suggest possible solutions of global validity. In the Carnic Alps and Sardinia, the Přídolí is subdivided into three zones: eosteinhornensis s.l., Lower and Upper detortus. The latter results after the subdivision of the former detortus Zone on the basis of the Last Appearance Datum of some coniform species (Dapsilodus obliquicostatus, Coryssognathus dubius and Panderodus recurvatus) that became extinct almost simultaneously in the latest Přídolí. Daps. obliquicostatus is chosen as the marker, being the most common and easily identifiable species. In the Lochkovian six zones are discriminated: hesperius, carlsi, transitans, eleanorae, trigonicus and pandora β. The hesperius Zone, which includes the postwoschmidti subzone in its upper part, is expanded to include most of the eurekaensis zone of the “global” scheme, because the marker Oz. eurekaensis is not present. The carlsi Zone corresponds to the upper part of the eurekaensis Zone and to the lower part of the former mid-Lochkovian delta Zone (= omoalpha Zone). The rest of the Middle Lochkovian is subdivided into the three zones (transitans, eleanorae and trigonicus) already proposed in Nevada and Spain, followed by the pandora β Zone. All the zones are discussed and checked for their applicability in other palaeogeographical regions.

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Loydell D; Vol. 87, issue 4, pages 651 - 660The graptolite biostratigraphy of the Rhuddanian (lower Llandovery, Silurian) of the E1-NC174 core, Murzuq Basin, Libya is described. The generally low diversity graptolite assemblages include both North African endemic taxa and cosmopolitan species. The lower part of the cored interval, below the ‘hot’ shale, is dominated by Normalograptus tilokensis, a species previously considered to be confined to the Upper Ordovician, but which almost certainly ranges into (or perhaps occurs only in) the lower Silurian. As in the BG-14 core, Jordan, the base of the ‘hot’ shale lies just above the first appearances of Neodiplograptus africanus and Normalograptus rectangularis. The latter species dominates throughout the mid Rhuddanian ‘hot’ shale interval, with the highest strata in the core, of late Rhuddanian age, yielding abundant Neodiplograptus fezzanensis.

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Legrand P; Vol. 87, issue 4, pages 661 - 668In the Touat region (Algerian Sahara), the most complete Palaeozoic succession occurs to the southwest of Adrar. In the Tamest section, the Silurian comprises the Fenourine Clay and the Touat Sandstone formations. The Fenourine Clay Formation consists mostly of silty claystones of which only the upper 150m crop out. At the base of the section, bivalves occur, followed by the graptolites Saetograptus chimaera aff. salweyi (Hopkinson) and Pristiograptus cf. P. tumescens minor (Wood) which are described and figured in this paper. The overlying Touat Sandstone Formation is 170m thick. It comprises silty claystones with several lenticular, sandy beds, surmounted by a sandy, calcareous bed. At the base of the sandstone, pieces of homalonotine trilobites, brachiopods and bivalves are present. Above the base, silty claystones, a ferrugineous siltstone bed and the first Tentaculoidea occur. A conglomeratic limestone bed yielding a Pragian fauna tops the formation. The ages are as follows: the lower and middle Silurian do not crop out. The graptolites at the base of the extant section belong to the associations σ3β which characterize the Saharan Ludlow Series (g3b) (Legrand 1981, 1985). The silty, clayey beds that follow may be the equivalent of the Přídolí (g3c). The fossiliferous beds at the base of the Touat Sandstone may also be of Přídolí age, or may indicate the base of the Lochkovian (g4c). These outcrops reveal an interesting evolution in terms of facies and faunal assemblages towards the Ougarta Mountains and the Gourara to the northwest and the Azzel Matti to the southeast.

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Marshall C, Thomas AT, Boomer IRay DC; Vol. 87, issue 4, pages 669 - 679High resolution δ13Ccarb data are presented for two composite sections in England covering much of the Homerian Stage. Micrite samples collected at ˜0.5 m intervals from outcrop and core in the Dudley area, West Midlands, span the uppermost Coalbrookdale, Much Wenlock Limestone and basal Lower Elton formations. Deposition there occurred in a mid-shelf setting.Asimilar suite of samples from the Wenlock type area, Wenlock Edge, Shropshire, represents a coeval sequence deposited closer to the shelf-basin margin. The successions concerned extend from the upper lundgreni to nilssoni graptolite biozones and provide a detailed record of variation in stable carbon isotope ratios across the well-known double-peaked Homerian positive excursion (Mulde Excursion), a time of significant global biological and chemical perturbation. In the West Midlands, this excursion occurs in the Much Wenlock Limestone Formation. The lower peak (Lower Quarried Limestone Member) has δ13Ccarb values rising to +5.5‰ VPDB. Values fall to +0.8‰ VPDB higher in the section before rising again to +4.1‰ VPDB (Nodular Beds Member). Analysis of lithofacies variation in this interval indicates two transgressive-regressive cycles, the two positive peaks of the excursion correlating with relative sea-level lows and the intervening dip with a relative sea-level high, the local expression of Johnson’s (2006) Highstand 5A. The double-peaked nature of the excursion at Dudley resembles that previously recorded for the area; however, our δ13Ccarb values are consistently 2‰ higher, and accord more closely with values published for sections elsewhere. The lower of the two peaks found in the West Midlands cannot be identified on Wenlock Edge, where δ13Ccarb values fluctuate somewhat around +2‰ VPDB. The upper peak, though less distinct, can be identified on Wenlock Edge with values rising to +3.8‰ VPDB. Correlations based on biostratigraphy, sequence stratigraphy and bentonite geochemistry suggest that not all changes in δ13Ccarb occurred synchronously in the two areas studied, despite their close proximity.

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Sadler PM; Vol. 87, issue 4, pages 681 - 694To correlate the burgeoning volume of biostratigraphic information available from the Silurian rocks of Baltica, it is advantageous to use numerical algorithms. Graphical correlation and related numerical methods routinely incorporate taxon range-ends and bentonites. Bentonites must be matched exactly. Local taxon ranges match or under-represent true ranges and may be stretched to fit hypotheses of correlation. Carbon isotope excursions are better handled as conservative uncertainty intervals – a new data class with properties and freedoms that are the opposite of taxon ranges. Uncertainty intervals match or over-represent truly correlative segments and inflexion points in the local series of isotopic ratios; they may be shrunk to fit correlations between sections. By these means, three fundamentally different kinds of stratigraphic information may be combined in a mutually supportive fashion without over-stating the precision of any of them. When incorporated as uncertainty intervals, Silurian isotopic excursions improve automated construction of inter-regional, ordinal time-lines of taxon first- and last-appearances at both the coarsest and finest resolution. The known succession of a few named excursions helps to stack relatively brief stratigraphic sections into their correct order in longer time-lines. The limits and details of individual excursions support some of the highest-resolution segments of optimized time-lines of individual taxon originations and extinctions. At intermediate scales, local taxon ranges are the unrivalled information source. For the best results, detailed taxon ranges, bentonite analyses and stable isotope time series need to be developed from the same rocks as often as possible.

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Kiipli T, Radzievičius S, Kallaste T, Kiipli E, Siir S, Soesoo A, Voolma M; Vol. 87, issue 4, pages 695 - 704In three drill cores in Latvia and Lithuania a thin (1 cm thick) altered volcanic ash bed with high concentrations of phosphorus (up to 3%), cerium (1%), lanthanum (0.5%) and strontium (2.5%), has been found close to the Aeronian/Telychian boundary (Llandovery, Silurian, ca 438 Ma). Small, millimetre-thick lenses within the ash bed contain up to 12% P and Sr, up to 6% Ce and 3% La. These elements occur as a solid solution of goyazite-florencite mineral. Additionally, authigenic K-feldspar and kaolinite occur in this ash bed. The high concentrations of REE elements, strontium and phosphorus suggest a carbonatite source magma, but the strontium isotope ratio contradicts that origin. Such a unique composition in a volcanic ash layer is a good basis for using it as a marker horizon for correlation of sections.

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Munnecke A, Cramer BD, Boon DP, Kharwat R, Aiken CL, Schofield DI; Vol. 87, issue 4, pages 705 - 712The Digital Integrated Stratigraphy Project (DISP) aims to eliminate the stratigraphical ambiguity associated with sample position within a stratigraphical section. For example, it is often impractical or impossible to compare one author’s measured section and data precisely against another author’s geographically identical measured section and data due to discrepancies in the measured thicknesses of units, variations in the assignments of litho- and chronostratigraphical terms, and/or the precise line of measured sections between authors. The DISP will provide a solution to this problem by producing a precise 3-D digital rendering of the exposure using Terrestrial Laser Scanning (TLS) LiDAR, Real-Time Kinematic (RTK) Global Navigation Satellite Systems (GNSS), overlain digital photography, and GIS software to produce a cm to mm-scale accurate digital version of a given exposure. Once available online as a permanent web-based digital resource for stratigraphy, researchers will be able to access the program and digital models of scanned exposures where they will have the means to log their sample positions directly onto the digital exposure while in the field, thus allowing unambiguous stratigraphical reference for future comparison. The Digital Integrated Stratigraphy Project represents the next generation of stratigraphical standard and can serve as the protocol for the future of high-resolution Palaeozoic Earth history research.

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