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  1. Article: Patterns in the distribution of Aptian rudists and corals within a sequence-stratigraphic framework (Maestrat Basin, E Spain)

    Bover-Arnal, Telm / Enric Pascual-Cebrian / Eulàlia Gili / Peter W. Skelton / Ramon Salas

    Sedimentary geology. 2015 May 15, v. 321

    2015  

    Abstract: The ecological zonation of, and environmental controls on rudist and coral assemblages on carbonate platforms of the Old World have received more attention for Late Cretaceous examples than for their Early Cretaceous counterparts. This study accordingly ... ...

    Abstract The ecological zonation of, and environmental controls on rudist and coral assemblages on carbonate platforms of the Old World have received more attention for Late Cretaceous examples than for their Early Cretaceous counterparts. This study accordingly investigates the vertical and lateral distribution of Aptian rudist bivalves and scleractinian corals on a carbonate platform succession from the western Maestrat Basin (E Iberian Peninsula). Here, colonial corals grew profusely on an isolated platform top environment during an earliest highstand stage of a long-term trend of relative sea level, as well as on marly slope settings during higher-frequency transgressive pulses. During the later highstand stage within a longer-term relative sea-level cycle, a facies belt dominated by autochthonous rudist bivalves overlaid the coral meadow that had developed on the isolated platform top. The internal part of this carbonate platform with rudists is dominated by slender elevator caprinids such as Caprina parvula, whereas requieniids and polyconitids predominate in the external zone. The abundance of caprinids in the internal platform is remarkable given that caprinid lithosomes of late Early Aptian age are usually rare in the northern margin of the Tethys. The proliferation of caprinids in this case was probably favoured by the apparently more isolated nature of the carbonate platform. On the slopes, the coral communities that flourished during higher-frequency transgressive pulses are overlain by carbonates with rudists, mainly requieniids, shed from the platform top during normal and forced regressive higher-frequency changes of relative sea level. Accordingly, the vertical change from coral-dominated to rudist-dominated facies in both platform top and slope settings records progradation. To decipher the long-term relative sea-level changes that controlled the deposition of this carbonate succession, a sequence stratigraphic analysis was performed. Two depositional sequences including a late Early Aptian (intra Dufrenoyia furcata Zone) forced regressive stage of relative sea level, which subaerially exposed and incised the Early Aptian succession to a depth of 21m, were recognised. The incisions were back-filled with peritidal deposits during the subsequent marine onlap. The rudist- and coral-bearing carbonates were deposited along platform top to slope profiles lacking a barrier margin, and hence, lagoon environments.
    Keywords Aptian age ; basins ; Bivalvia ; carbonates ; corals ; ecological zones ; Late Cretaceous epoch ; meadows ; Scleractinia ; sea level ; Iberian Peninsula ; Spain
    Language English
    Dates of publication 2015-0515
    Size p. 86-104.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 216739-6
    ISSN 0037-0738
    ISSN 0037-0738
    DOI 10.1016/j.sedgeo.2015.03.008
    Database NAL-Catalogue (AGRICOLA)

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  2. Article: Depositional biofacies model for post-OAE1a Aptian carbonate platforms of the western Maestrat Basin (Iberian Chain, Spain)

    Gili, Eulàlia / Peter W. Skelton / Telm Bover-Arnal / Ramon Salas / Antoni Obrador / Mükerrem Fenerci-Masse

    Palaeogeography, palaeoclimatology, palaeoecology. 2016 July 01, v. 453

    2016  

    Abstract: Two well exposed platform successions of late Early Aptian age developed in the central part of the Galve sub-basin of the Maestrat Basin: the highstand ‘Camarillas–El Morrón’ platform, and the succeeding ‘Las Mingachas’ small lowstand ... ...

    Abstract Two well exposed platform successions of late Early Aptian age developed in the central part of the Galve sub-basin of the Maestrat Basin: the highstand ‘Camarillas–El Morrón’ platform, and the succeeding ‘Las Mingachas’ small lowstand platform, built out downslope in the former basin. Both platforms had a flat-topped non-rimmed depositional profile, showing similar platform-top to slope biofacies, which are described here in both qualitative and quantitative terms. The proximal platform top succession is characterized by a Toucasia-dominated rudist association. The margins of the two platforms consist of massive limestone characterized by a Polyconites-dominated association, in which clusters of Polyconites hadriani in life position are joined by both branching and domal corals, as well as the oyster-like Chondrodonta and nerineid gastropods. In Las Mingachas platform, where the massive rudist- and coral-rich platform limestones pass laterally into the slightly more marly and recessive clinoforms of the upper slope facies, Polyconites is especially abundant. Basinwards these slope deposits pass into basinal marls with orbitolinids and ammonoids. The distribution of the two distinct rudist associations recognized here is attributed to the different environmental tolerances of the rudists with respect to such factors as current regime and rate of sedimentation. The prevalence of polyconitids, in place of caprinids, in these late Early Aptian platform margin facies makes a striking contrast with older, earliest Aptian platforms.
    Keywords Aptian age ; Gastropoda ; basins ; corals ; limestone ; models ; Spain
    Language English
    Dates of publication 2016-0701
    Size p. 101-114.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 417718-6
    ISSN 0031-0182
    ISSN 0031-0182
    DOI 10.1016/j.palaeo.2016.03.029
    Database NAL-Catalogue (AGRICOLA)

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  3. Article: Response of proto-North Atlantic carbonate-platform ecosystems to OAE1a-related stressors

    Huck, Stefan / Adrian Immenhauser / Karl B. Föllmi / Melody Stein / Nicolas Christ / Peter W. Skelton / Ulrich Heimhofer

    Sedimentary geology. 2014 Nov., v. 313

    2014  

    Abstract: Integrated biostratigraphic–chemostratigraphic studies provide evidence that the proto-North Atlantic realm witnessed major changes in carbonate platform production in the run-up of the Early Aptian oceanic anoxic event (OAE) 1a. Whereas pervasive growth ...

    Abstract Integrated biostratigraphic–chemostratigraphic studies provide evidence that the proto-North Atlantic realm witnessed major changes in carbonate platform production in the run-up of the Early Aptian oceanic anoxic event (OAE) 1a. Whereas pervasive growth of Lithocodium microencrusters represents an early harbinger of OAE1a-related environmental perturbation, the subsequent replacement of oligotrophic rudist-coral-nerineid by mesotrophic orbitolinid-oyster communities was clearly associated with the event itself. In order to test the supra-regional relevance of this major community replacement, two shallow-water sections in the southern Lusitanian Basin (Portugal) are investigated by means of geochemistry (carbon and oxygen isotopes), cement petrography and detailed sedimentological analysis. The focus is on a regional, prominent discontinuity surface (S4) at the transition between oligotrophic and mesotrophic carbonate platform production, which might indicate that the major biotic change could have been associated with a phase of non-sedimentation and possibly erosion. The studied sections (São Julião, Crismina) provide evidence that the major Early Aptian biotic turnover was preceded by numerous subordinate but significant changes in platform ecology, which mirrored a series of progressive short-term environmental changes in the course of OAE1. Several transient mass occurrences of orbitolinids indicate repeated phases of ecological stress arguably due to enhanced nutrient input and deepening. Small-scale sea-level changes at parasequence level below the major discontinuity surface are revealed by alternations of rudist assemblages dominated by clinger or recumbent forms as well as intercalated hardground and subaerial exposure stages. Expanded phases of subaerial exposure, however, can be largely ruled out following the geochemical and cement-petrographic data presented here. Enhanced continent-derived siliciclastic input characterising the lower orbitolinid-oyster dominated limestones is in support of a shift to more humid conditions during the middle Early Aptian. This is in line with palaeoclimatic data, which propose a southward movement of the mid-latitude arid climate belt during this time. The documented rapid replacement of oligotrophic assemblages by various environmental-stress adapted carbonate platform communities might be seen as explanation for ongoing Early Aptian proto-North Atlantic carbonate production during a time of widespread platform demise and drowning in the northern Tethyan realm.
    Keywords Aptian age ; arid zones ; basins ; carbon ; cement ; ecosystems ; geochemistry ; isotopes ; latitude ; oxygen ; sea level ; Atlantic Ocean ; Portugal
    Language English
    Dates of publication 2014-11
    Size p. 15-31.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 216739-6
    ISSN 0037-0738
    ISSN 0037-0738
    DOI 10.1016/j.sedgeo.2014.08.003
    Database NAL-Catalogue (AGRICOLA)

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  4. Article: A synoptical classification of the Bivalvia (Mollusca)

    Carter, J.G. / Altaba, C.R. / Anderson, L.R. / Araujo, R. / Biakov, A.S. / Bogan, A.E. / Campbell, D.C. / Campbell, M. / Chen, J. / Cope, J.C.W. / Delvene, G. / Dijkstra, H.H. / Fang, Z. / Gardner, R.N. / Gavrilova, V.A. / Goncharova, I.A. / Harries, P.J. / Hartman, J.H. / Hautmann, M. /
    Hoeh, W.R. / Hylleberg, J. / Jiang, B. / Johnston, P. / Kirkendale, L. / Kleemann, K. / Koppka, J. / Kříž, J. / Machado, D. / Malchus, N. / Márquez-Aliaga, A. / Masse, J.-P. / McRoberts, C.A. / Middelfart, P.U. / Mitchell, S. / Nevesskaja, L.A. / Özer, S. / Pojeta Jr / J. / Inga V. Polubotko, Jose Maria Pons, Sergey Popov, Teresa Sánchez, André F. Sartori, Robert W. Scott, Irina I. Sey, Javier H. Signorelli, Vladimir V. Silantiev, Peter W. Skelton, Thomas Steuber, J. Bruce Waterhouse, G. Lynn Wingard, / Thomas Yancey1 / Polubotko, I.V. / Pons, J.M. / Popov, S. / Sánchez, T. / Sartori, A.F. / Scott, R.W. / Sey, I.I. / Signorelli, J.H. / Silantiev, V.V. / Skelton, P.W. / Steuber, T. / Waterhouse, J.B. / Wingard, G.L. / Yancey, T.

    Abstract: PrefaceThis classification summarizes the suprageneric taxonomy of the Bivalvia for the upcoming revision of the Bivalvia volumes of the Treatise on Invertebrate Paleontology, Part N. ...

    Abstract PrefaceThis classification summarizes the suprageneric taxonomy of the Bivalvia for the upcoming revision of the Bivalvia volumes of the Treatise on Invertebrate Paleontology, Part N.
    Document type Article
    Database AGRIS - International Information System for the Agricultural Sciences and Technology

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