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  1. Article: Eustasy in the Aptian world: A vision from the eastern margin of the Iberian Plate

    Bover-Arnal, Telm / Salas, Ramon / Guimerà, Joan / Moreno-Bedmar, Josep Anton

    Global and planetary change. 2022 May 20,

    2022  

    Abstract: Eustatic controls on Early Cretaceous (Aptian) sedimentation in the western Tethys are discerned in outcrops of carbonate platforms that developed in the Maestrat rift basin located at the eastern margin of the Iberian Plate. The relative sea-level ... ...

    Abstract Eustatic controls on Early Cretaceous (Aptian) sedimentation in the western Tethys are discerned in outcrops of carbonate platforms that developed in the Maestrat rift basin located at the eastern margin of the Iberian Plate. The relative sea-level fluctuations with a dominant eustatic contribution investigated had estimated magnitudes of between 50 and 60 m in <0.9 My and ≥ 115 m in <3 My, and occurred respectively during the late early and early late Aptian. The major relative sea-level falls of mainly eustatic nature were recorded as forced regressive sedimentary wedges or as incised valleys carved into highstand carbonate platforms, whereas the subsequent sea-level rises back-filled the incised topographic lows created, or favoured the development of lowstand platforms. The finding of 50–115 m amplitude fluctuations of Aptian age is of relevance in that show magnitudes of relative sea-level fall in the order of that recorded during the last glacial maximum in the late Pleistocene (c. 120 m). The current knowledge on Cretaceous climate history shows an Earth with non-uniform greenhouse conditions. However, geological evidence of temporary icehouse states with ice-cap magnitudes close to late Pleistocene scales during the Aptian is absent, or at least has not been reported so far. Thus, although falling within the glacio-eustatic domain, the driving processes of these widespread drops and subsequent rises in relative sea level remain a mystery. Finally, this paper is an example of how sequence stratigraphy can be applied to carbonate successions, and of how this methodology indeed permits to unravel ancient relative sea-level fluctuations which controlled carbonate production and accumulation.
    Keywords Aptian age ; Pleistocene epoch ; basins ; carbonates ; climate ; greenhouses ; sea level ; stratigraphy ; topography
    Language English
    Dates of publication 2022-0520
    Publishing place Elsevier B.V.
    Document type Article
    Note Pre-press version
    ZDB-ID 2016967-X
    ISSN 0921-8181
    ISSN 0921-8181
    DOI 10.1016/j.gloplacha.2022.103849
    Database NAL-Catalogue (AGRICOLA)

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  2. Article: Palaeonitella trifurcata n. sp., a cortoid-building charophyte from the Lower Cretaceous of Catalonia

    Martín-Closas, Carles / Segura-Altés, Ricard / Pérez-Cano, Jordi / Bover-Arnal, Telm / Sanjuan, Josep

    Review of palaeobotany and palynology. 2021 Dec., v. 295

    2021  

    Abstract: Palaeonitella trifurcata n. sp. is a minute ecorticate thallus of a charophyte from a non-marine upper Barremian–Lower Aptian section of the Garraf Massif, near Barcelona (Catalonia, Spain). Whorls of trifurcated branchlets built glomerules about 1 mm ... ...

    Abstract Palaeonitella trifurcata n. sp. is a minute ecorticate thallus of a charophyte from a non-marine upper Barremian–Lower Aptian section of the Garraf Massif, near Barcelona (Catalonia, Spain). Whorls of trifurcated branchlets built glomerules about 1 mm across. Small radial branchlets were trifurcated once in three terminal acuminate dactyls. Longer and more robust branches, two per whorl emerge from a basal trifurcation, bore opposite secondary branchlets and ended in three terminal branchlets bearing one oospore. The whole set of characters suggests affinity with Nitella, making of this fossil one of the oldest and unique possible records of thalli of this extant genus.The thallus of P. trifurcata n. sp. was encrusted by a thin micrite film, and additionally, the whorls were coated by a thicker crust while the plant was still alive. It is suggested that this crust was formed upon the periphyton which grew perhaps upon a mucilage covering the whorls and apical heads, as it happens in extant Nitella. After encrustation, a small (ca. 5 mm across) constructive micrite envelope, called a cortoid, was formed attached to the plant, preserving in the inside the thallus articulated and slightly encrusted. Once the plant died, such cortoids accumulated on the lake bottom and were buried and lithified, forming a “cortolite”. This is the first report of constructive micrite envelopes protecting delicate and poorly calcified charophyte thalli from being destroyed.
    Keywords Cretaceous period ; Nitella ; fossils ; lakes ; mucilages ; oospores ; paleobotany ; palynology ; periphyton ; thallus ; Spain
    Language English
    Dates of publication 2021-12
    Publishing place Elsevier B.V.
    Document type Article
    ISSN 0034-6667
    DOI 10.1016/j.revpalbo.2021.104523
    Database NAL-Catalogue (AGRICOLA)

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  3. Article ; Online: Forward numerical modelling constraining environmental parameters (Aptian carbonate system, E Iberia)

    Gratacos, Oscar / Bover-Arnal, Telm / Clavera-Gisbert, Roger / Carmona, Ana / García-Sellés, David

    2021  

    Abstract: The facies distribution in time and space of sedimentary successions is controlled by a complex interplay between physical, chemical and biological processes, which are nowadays difficult to construe from the geological record. Numerical models ... ...

    Abstract The facies distribution in time and space of sedimentary successions is controlled by a complex interplay between physical, chemical and biological processes, which are nowadays difficult to construe from the geological record. Numerical models constitute a valuable tool to identify and quantify such controlling factors permitting a reliable 3D extrapolation and prediction of stratigraphic and facies architectures beyond outcropping rock strata. This study assesses the roles of three controlling parameters being carbonate production rate, relative sea-level changes and terrigenous clastic sediment supply, on the evolution of an Aptian carbonate system. The SIMSAFADIM-CLASTIC, a 3D process-based sedimentary-stratigraphic forward model, was used for this evaluation. The carbonate succession modelled crops out in the western Maestrat Basin (E Iberia), and corresponded to a platform-to-basin transition comprising three depositional environment-related facies assemblages: platform top, slope and basin. Testing of geological parameters in forward modelling results in a wide range of possible 3D geological scenarios. The documented distribution of facies and sequence-stratigraphic framework combined with a virtual outcrop model were used as a reference to perform geometric (quantitative) and architectural and stacking pattern (qualitative) research by model-data comparison. The time interval modelled spans 1450 ky. The best-fit simulation run characterizes and quantifies (1) relative sea-level fluctuations recording five different genetic types of deposit (systems tracts) belonging to two depositional sequences as expected from field-data analysis, (2) a rate of terrigenous clastic sediment input ranging between 0.5 and 2.5 gr/s, and (3) a mean autochthonous carbonate production maximum rate of 0.08 m/ky. Furthermore, the quantitative and qualitative sensitivity tests carried out highlight that the fluctuation of relative sea level exerted the main control on the resulting stratigraphic and facies architectures, ...
    Subject code 550
    Language English
    Publisher Elsevier
    Publishing country de
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Book ; Online ; Thesis: The Aptian evolution of the Galve sub-basin (Maestrat Basin; E Iberia)

    Bover-Arnal, Telm

    2010  

    Author's details von Telm Bover-Arnal
    Language English
    Size Online-Ressource, Ill., graph. Darst
    Document type Book ; Online ; Thesis
    Thesis / German Habilitation thesis Univ., Diss.--Bayreuth, 2010
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  5. Book ; Online ; Thesis: The Aptian evolution of the Galve sub-basin (Maestrat Basin, E Iberia)

    Bover-Arnal, Telm [Verfasser]

    2010  

    Author's details vorgelegt von Telm Bover-Arnal
    Keywords Geowissenschaften ; Earth Sciences
    Subject code sg550
    Language English
    Document type Book ; Online ; Thesis
    Database Digital theses on the web

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  6. 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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  7. Article: Corals on the slope (Aptian, Maestrat Basin, Spain)

    Bover-Arnal, Telm / Löser, Hannes / Moreno-Bedmar, Josep Anton / Salas, Ramon / Strasser, André

    Cretaceous research. 2012 Oct., v. 37

    2012  

    Abstract: The term “reef” has been frequently misused when applied to fossil coral communities. Our popular but biased view of coral community structure based on the idyllic picture of recent tropical reefs has failed to recognize that, in many fossil examples, ... ...

    Abstract The term “reef” has been frequently misused when applied to fossil coral communities. Our popular but biased view of coral community structure based on the idyllic picture of recent tropical reefs has failed to recognize that, in many fossil examples, alternative states of community structure with no or limited framework may occur. The Aptian colonial scleractinians analysed in the western Maestrat Basin (eastern Spain) constitute an example of non-reef-building coral populations, which thrived in marly slope settings. These corals developed within the photic zone but below the storm wave-base. All colonies are found well-preserved in life position. They are mostly decimetres in size and mainly occur isolated giving rise to a continuous and uniform (dominated by domal and massive forms) unbound growth fabric with a low to medium degree of development (coral skeletal volume = 5–20%). Occasionally, however, colonies growing on top of each other forming small metre-sized bioherms are also present. A total of 21 species were identified. Coral diversity in each sample location varies between three and nine species. These numbers of species are comparable with those exhibited by coeval coral assemblages from other basins of the Tethys, but are comparatively low when compared with diversities exhibited by many Recent and fossil coral communities. The corals studied apparently found optimal ecological conditions for their development on the marly slopes of the western Maestrat Basin. This is primarily expressed in the unusually large dimensions (up to 2.3 m in width) of some of the coral colonies when compared to other Cretaceous occurrences, and in the persistence and resilience of the coral populations. The observed coral genera and species (suborders Archeocaeniina, Faviina, Fungiina and Microsolenina) are very common in the time interval between the Barremian and the Early Albian and most of them have been reported from several other localities in the western and central Tethyan realm. In addition, the coral-bearing levels also contain the poorly known and exotic genera Agrostyliastraea and Procladocora. There are no significant differences at species level or in community structure between the Early and Late Aptian faunas investigated. Therefore, the coral communities as well as the environmental conditions controlling them would have been relatively stable during the time intervals when these corals flourished. An important palaeoecological implication is that comparatively low species diversities and the absence of reef frameworks do not necessarily imply unfavourable environmental conditions for coral growth. Furthermore, this study may serve as an example for the analysis of other level-bottom coral communities displaying a loose growth fabric.
    Keywords basins ; community structure ; corals ; environmental factors ; euphotic zone ; fossils ; interspecific variation ; paleoecology ; reefs ; storms ; topographic slope ; Spain
    Language English
    Dates of publication 2012-10
    Size p. 43-64.
    Publishing place Elsevier Ltd
    Document type Article
    ISSN 0195-6671
    DOI 10.1016/j.cretres.2012.03.001
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  8. Article: Uppermost lower aptian transgressive records in mexico and spain: chronostratigraphic implications for the Tethyan sequences

    Moreno-Bedmar, Josep A. / Bover-Arnal, Telm / Barragán, Ricardo / Salas, Ramon

    Abstract: A widespread marine transgression, which began at the very end of the Early Aptian, is well recorded in Mexico and Spain. In Mexico, this transgression was the most important Aptian transgressive event and its record begins in the Dufrenoyia justinae ... ...

    Abstract A widespread marine transgression, which began at the very end of the Early Aptian, is well recorded in Mexico and Spain. In Mexico, this transgression was the most important Aptian transgressive event and its record begins in the Dufrenoyia justinae Zone, whereas in Spain the corresponding transgression is registered in the uppermost part of the Dufrenoyia furcata Zone. The basal age of this Tethyan transgression does not correspond exactly to any of the Lower Aptian third-order sequences as reported in the literature. In Spain, the most important Aptian transgressive event was earlier, corresponding to the Tethyan sequence Ap3, which is well-defined below this transgression reported herein. Consequently, it is possible to correlate this later transgressive event with the third-order Ap4 sequence, which has commonly been attributed to the Upper Aptian. The available ammonoid data allow us to correct the basal age of the transgression, and to correlate the start of the ammonite record in Mexico with the Tethyan sequence Ap4.
    Language English
    Document type Article
    Database AGRIS - International Information System for the Agricultural Sciences and Technology

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