The Westernmost Tethys Blog Geology mapping, basin analysis and 3D modeling

02/15/2021

Middle Eocene carbonate platforms of the westernmost Tethys

A study of the paleoenvironmental evolution of the middle Eocene platforms recognized in the westernmost Tethys has been carried out in the well exposed middle Eocene succession from Sierra Espuña-Mula basin (Betic Cordillera, S Spain). Eight microfacies (Mf1 to Mf8) have been recognized, based mainly on fossil assemblages (principally larger benthic foraminifera), and rock texture and fabric.

Environmental microfacies distribution for the Middle Eocene marine Depositional Sequence 2 (Malvariche andCánovas fms) in Sierra Espuña, arranged from proximal to distal depositional environments: Mf3, Inner ramp lagoon, upper subtidal environment; Mf5, Inner ramp seagrass, euphotic subtidal environment; Mf6 – Mf7, Inner ramp, euphotic lower subtidal environment; Mf2, Proximal middle ramp LBF accumulations (nummulitids), mesophotic environment; Mf1, Proximal middle ramp maërl, mesophotic environment; Mf8, Distal middle ramp LBF accumulations (orthophragminids), mesophotic environment; Mf4, Outer ramp lacking Large Bethic Foraminifera (LBF), oligophotic environment. Ramp subdivision is based on Burchette and Wright (1992), and photic zones are analogous to those described by Pomar et al. (2017), with a ‘mesophotic zone’ comprised between lower limit of occurrence of marine vegetation and the storm wave base (swb).

 

The fossiliferous assemblage can be asigned to the ‘subtropical’ heterozoan association or to the low-latitude ‘foralgal facies’ , which are dominated by non-framework building, light-dependent biota such as perforate larger benthic foraminifera, coralline algae, and sometimes green algae and solitary corals. Larger benthic foraminifer assemblages, corresponding from euphotic to oligophotic conditions and the large surface showed, suggest a progressive marine ramp under essentially oligotrophic conditions. Eventually, supply of detrital sediments from the continent and/or upwelling currents increasse the nutrients of marine waters. Comparision with other Tethyan sectors allows stating that coral-reef buildups (z-corals) were widespread on shallow platforms of the central and eastern Tethys Ocean, but that these were neither of great dimensions nor dominant because of the much more dominant presence of larger benthic foraminifera. Moreover, these coral constructions were completely absents in the westernmost Tethys. The dominance of larger benthic foraminifera and the absence of z-corals in the westernmost Tethys is explained by particular paleogeographic features due to the occurrence of a narrow and deep oceanic branch (i.e., the Maghrebian Flysch Basin) connecting the Tethys with the Atlantic Ocean.

Biochronostratigraphic chart with numerical time scale, magnetochrons, magnetic polarity, planktonic foraminifera and calcareous nannoplankton zones based on GTS 2012 (Gradstein and Ogg, 2012), correlated with shallow benthic zones (SBZ). Interpretations of main climatic events, trophic resources continuum, LBF specific diversity and coral events in the Tethyan domain are also represented. A synthetic column with the stratigraphic formations and the main trophic conditions and Large Bethic Foraminifera (LBF) and coral (*) events of the Sierra Espuña-Mula Basins are also included.

The various issues regarding the morphological characters and evolution of larger benthic foraminifera in the study area, such as sizes of tests, specific diversity and/or intraspecific variability, number of appearances and last occurrences during the middle Eocene are analyzed and compared with those appearing in other Tethyan sectors. In addition, the early to late Bartonian boundary is recognized in the study area as critical for the biological change as in other shallow-marine environments along the Tethys margins.

Cite as: Martín-Martín, M., Guerrera, F., Tosquella, J., Tramontana, M., 2021. Middle Eocene carbonate platforms of the westernmost Tethys. Sediment. Geol. 415, 105861. doi:10.1016/j.sedgeo.2021.105861

 

02/01/2021

Sedimentary History and Palaeogeography of the Cenozoic clastic wedges of the Malaguide Complex, Internal Betic Cordillera, Southern Spain

Filed under: Betics,geodynamic evolution — Tags: , , , , , — messinianalicante @ 8:59 PM

The Cenozoic sedimentary cover of the Malaguide Complex (Internal Betic Cordillera, Spain), in the Almería and Málaga areas, consists of a suite of sedimentary successions from continental and shallow-marine to deep-marine environments. Structural and stratigraphic relations, and petrological and geochemical signatures reveal the sedimentary evolution of the Cenozoic Malaguide Complex (CMC) from pre-orogenic (Palocene-Eocene) to syn-orogenic (Oligocene-Early Miocene) stages.

Figure 1. A, Geological sketch map of the Betic Cordillera. B, Paleogeographic reconstruction of the central-western Mediterranean area showing the position of the Mesomediterranean Microplate. C, The Internal Zones of others alpine chains of the Circum-Mediterranean belts (i.e. Rif, Tell, Calabria-Peloritani and Apennine chains). Modified from Martín-Algarra (1987), Guerrera et al. (1993, 2005), Perrone et al. (2006), Critelli et al. (2008), Perri et al. (2013).

Sandstones detrital modes of the overall succession are heterogeneous testifying to a multi-source area, marked by exhumation of the Malaguide basement terranes and of the Internal Betic Zone (Alpujárride Complex) in lower position. Pre-orogenic and syn-orogenic strata consist of four main depositional sequences: the Mula Group (Paleocene), the Xiquena Group (Eocene) for the preorogenic successions; and Ciudad Granada Group (Oligocene-Aquitanian) and Viñuela Group (Burdigalian) for the synorogenic successions. Pre-orogenic strata evolve from intra-arenite to hybrid arenites to progressive increase of sandstones in abundance of detrital supply from sedimentary cover of the internal Betic units. The unroofing history of the internal Betic Units, predominantly in the Malaguide Complex, is clearly testified in strata of the synorogenic clastic units, where detrital supply is coming from the Malaguide Complex. Sedimentary lithic fragments were derived from the Mesozoic strata of the Malaguide Complex while metamorphic detritus is related to the Internal Betic Zone basement that was exhumed starting from the Oligocene. Pre-orogenic mudrocks mainly show abundance of calcite and dolomite over quartz and phyllosilicates. Syn-orogenic mudrocks, record an abrupt decrease in calcite and dolomite and an increase of phyllosilicate, quartz and feldspars mainly in the Malaga section. The geochemical signatures attest to a compositional variation of the samples from pre-to-synorogenic successions, with palaeoweathering indices showing moderate values and a weak up-section decrease. The Cenozoic Malaguide Complex played a key role in the geodynamic evolution of the Betic Cordillera, representing the key tectonic element of the western Mesomediterranean domains.

 

Figure 2 Mineralogical variations along the studied stratigraphic formations.

Cite as: Critelli, S., Martín-Martín, M., Capobianco, W., Perri, F., 2021. Sedimentary history and palaeogeography of the Cenozoic clastic wedges of the Malaguide Complex, Internal Betic Cordillera, southern Spain. Mar. Pet. Geol. 124, 104775. https://doi.org/https://doi.org/10.1016/j.marpetgeo.2020.104775

 

12/31/2020

Visiting the Monduver geologic dome

Filed under: Betics — Tags: , — messinianalicante @ 7:39 AM

Students of the third course of Geology of the Alicante University within the subject of Regional Geology: visit Jarafuel triassic section, Montealegre del Castillo triassic section, Sot de Chera Jurassic section, Valencia Albufera, and Monduver geologic dome.

The dome was investigated during the 70s as was drilled by the Jaraco borehole.

Alicante University students at the Moduver mountain. At the back the Cullera city.

11/27/2020

Mula field work

Filed under: Betics — Tags: , , — messinianalicante @ 11:30 AM

Students of the third course of Geology of the Alicante University within the subject of Mapping 2: visit North of Mula village. Working in the Malaguide complex non-metamorphic rocks.

The visit took place from October 21th until 24th of 2020 and the professor in charge was Manuel Martín-Martín.

Students of the Alicante University Geology Degree at Mula (Murcia) during the Covid-19 pandemic 2020.

09/08/2020

Paul Fallot visit to the Crevillente Sierra on 1931

Filed under: Betics — Tags: , , , — messinianalicante @ 9:24 AM

A compilation of geological landscape images of the Crevillente Sierra prior to the Spanish civil war found in  the historical archives have been made. Specifically from the authors Daniel Jiménez de Cisneros and Hervás, Bartolomé Darder Pericàs and Paul Fallot. Many different works have been carried out on the first two authors, while the stereographic photographs of the Paul Fallot Fund in the Archive of the University of Granada  are mentioned for the first time.

During the preparation of the Symposium Tribute to D. Daniel Jiménez de Cisneros y Hervás, in 2004, part of the glass gelatin silver emulsions in the Jimenez de Cisneros collection were cataloged and scanned.

Tables are made with the description of the glasses and some images that have been described in previous works are shown. The conservation of this material is worthwhile because you can see how the landscape of the mountains has changed from the beginning of the last century to the present day.

Stereoscopic pictures number 1849 of the Paul Fallot Fund of the Granada University. Numbered as 2452 by its author and described as: “Néogene Colina del Castillo S. de Crevillente P.F. 31” (Paul Fallot 1931). Bottom El Frare from el Pla taken on February 13th of 2004 by J. E. Tent-Manclus.

Cite as: Tent-Manclús, J. E., Lancis, C. y Baeza Carratalá, J. F. (2019): Las fotografías realizadas para el studio geológico de la Sierra de Crevillente a principios del siglo XX. In: Daniel Jiménez de Cisneros Centenario de sus trabajos sobre geología y paleontología de la Sierra de Crevillent (Belmonte Mas y Satorre Pérez, A. Eds.). Ayuntamiento de Crevillent. Concejalía de Cultura. 247-259.

12/17/2019

New model for the Betic Flysch Basin

Filed under: Betics,Campo de Gibraltar — Tags: , — messinianalicante @ 1:06 PM

The Flysch Complex extends, with equivalent stratigraphic and tectonic features, from the Betic Cordillera to the Rif, Argelian and Tunisian Tells, Sicily, Calabria and the southern-central Apennines. In the Betic Chain, it extends from the Campo de Gibraltar to the Vélez Rubio-Lorca region. This complex is a thrust-and-fold system (when structurally organised) or a tectonosedimentary mélange (when showing a rather chaotic structure). In the western Betic Cordillera, the Campo de Gibraltar Flysch Complex widely overthrusts the External Zones and, in turn, the Alborán Domain (Frontal Units in particular) thrusts onto it.

The Flysch Complex is mainly made of Lower Cretaceous to lower Burdigalian turbiditic siliciclastic (and subordinately carbonatic) sandstones interlayered with varicoloured clays. Since the latest Oligocene the successions show synorogenic character.

The Cretaceous successions of the Alborán (internal domain in the figure) domain record the post-rift evolution of the proximal to distal parts of a divergent Tethyan paleomargin, while those of the Campo de Gibraltar Flysch Complex record the evolution of the oceanic basin. The Alborán and the Campo de Gibraltar Flysch Complex domains were later transformed into a convergent continental margin (Oligocene to Early Miocene) that later evolved to a collisional setting (Middle to Late Miocene).

Paleogeographic and geodynamic evolutionary model of the Western Mediterranean area during the deposition and deformation of the syn–orogenic deposits of the Flysch units.

Cite as: Jabaloy Sánchez, A., Martín-Algarra, A., Padrón-Navarta, J.A., Martín-Martín, M., Gómez-Pugnaire, M.T., López Sánchez-Vizcaíno, V., Garrido, C.J., 2019. Lithological Successions of the Internal Zones and Flysch Trough Units of the Betic Chain, in: Quesada, C., Oliveira, J.T. (Eds.), The Geology of Iberia: A Geodynamic Approach: Volume 3: The Alpine Cycle. Springer International Publishing, Cham, pp. 377–432. https://doi.org/10.1007/978-3-030-11295-0_8

11/12/2019

Field trip to Granada

Filed under: Betics — Tags: , — messinianalicante @ 3:03 PM

Students of the third course of Geology of the Alicante University within the subject of Mapping 2: visit Benalúa in the Guadix basin.

The visit took place from October 23th until 26th of 2019 and the professor in charge was Manuel Martín-Martín.

 

10/25/2019

Tectonic breakup in the Eastern Betic zone

Six Paleogene-Aquitanian successions have been reconstructed in the Alicante area (eastern External Betic Zone). The lithofacies association evidences “catastrophic” syn-sedimentary tectonic processes consisting of slumps, mega-olisthostromes, “pillow-beds” and turbiditic deposits  (Figure 1).

Figure 1. Field photos of the main macro-tectofacies found in the study area (see text for details). (A) A typical Lower Eocene sequence of the Villafranqueza section. (B) Calcarenite turbidite with convolute bedding (Lower Eocene, Villafranqueza). (C) Two Oligocene carbonate turbiditic channelized bodies (Busot). (D) Oligocene conglomeratic bed with erosional base and reverse grading of clasts, typical of debris flow deposits (Busot). (E) Oligocene slumped level and pillow-beds (Busot). (F) Oligocene mega-flute casts indicating a northwestwards-directed paleocurrents (Relleu). (G) Oligocene pillow-beds (Relleu). (H) Oligocene mega-olisthostrome with huge blocks (Playa Nudista). (I) Slumped megabed (Playa Nudista).

This kind of sedimentation is related to unconformity surfaces delimiting sequence and para-sequence cycles in the stratigraphic record (Figure 2).

Figure 2. Unconformities, associated gaps of the Eocene and Oligocene-Miocene depositional sequences compared with the sedimentary cycles of (Vera, 2000). The figure shows a basement tectonic interpreted as folding during the Eocene and blind thrust during the Oligocene-Aquitanian. The different evolutionary trends are discussed in the text.

The data compiled have enabled the reconstruction of the Paleogene-Aquitanian paleogeographic and geodynamic evolution of this sector of the External Betics. During the Eocene the sedimentary basin is interpreted as a narrow trough affected by (growth) folding related to blind thrust faulting with a source area from the north-western margin, while the southeastern margin remained inactive. During the Oligocene-Aquitanian, the sourcing margin became the southeastern margin of the basin affected by a catastrophic tectonic (Figure 3).

Figure 3. Paleogeographic-geodynamic model of the Alicante Trough during Eocene and Oligocene-Miocene times.

The activity of the margins is identified from specific sediment sources area for the platform-slope-troughsystem and from tectofacies analysis. The southeastern South Iberian Margin is thought to be closer to the Internal Betic Zone, which was tectonically pushing towards the South Iberian Margin. This pushing could generate a lateral progressive elimination of subbetic paleogeographic domains in the eastern Betics (Figure 4).

Figure 4. Synthetic Oligocene-Aquitanian paleogeographic-geodynamic model proposed for the western.

This geodynamic frame could explain the development of such “catastrophic” tectono-sedimentary processes during the Late Oligocene-Early Miocene.

Cite as: Guerrera, F. and Martín-Martín, M. (2014): Paleogene-Aquitanian tectonic breakup in the Eastern External Betic Zone (Alicante, SE Spain). Revista de la Sociedad Geológica de España, 27(1): 271-285.

 

09/23/2019

Jiménez de Cisneros course field trip to the Crevillente Sierra

Filed under: Betics — Tags: , , — messinianalicante @ 11:03 AM

The field trip of the he summer school course of the University Miguel Hernandez  entitled “Jimenez de Cisneros, pioneer in the geological and paleontological investigation in the Southern Alicante” took place on september 5th, 2019.

The participants visit the Los Molinos educative center and then waked along the dirt road to the Pouet de la Mel spring.

The fist photography show the conductor of this field trip will be our collegue José Enrique Tent-Manclús teaching the finimessinian transgressive surface on the background of the picture.

The second fotography show the all participants in the field trip near the Pouet the la Mel spring with the Sierra de Crevillente Jurassic at the back.

More information about the Crevillente course here.

09/01/2019

Tethyan to Mediterranean Evolution

Filed under: Betics,Tethys — Tags: — messinianalicante @ 5:49 PM

Message from the Guest Editor

Dear Colleagues,

Several geological modeling studies on the geodynamic and paleogeographic Alpine (Eo-Alpine during the Cretaceous–Paleogene; Neo-Alpine during the Oligocene– Miocene) evolution of the Mediterranean have been published without consensus in the last four decades. Therefore, a Special Issue dedicated to “Tethayan to Mediterranean evolution” seems justified. Studies that consider the geodynamic and/or paleogeographic evolution of the entire Mediterranean area or a part of this area will be welcome. The proposal can be focused on stratigraphic, sedimentological, petrographic, or tectonic data, or geophysical interpretations and reconstructions based on principles of Plate Tectonics using GPlates or similar software. The papers that are published in this Special Issue can contribute to clarifying and updating the state of our knowledge about this controversial theme.

Message from the Editorial Board

T h e Journal of Marine Science and Engineering (JMSE; ISSN 2077-1312) is an international peer-reviewed open access journal which provides an advanced forum for studies related to marine science and engineering. The journal aims to provide scholarly research on a range of topics, including ocean engineering, chemical oceanography, physical oceanography, marine biology and marine geosciences. We invite you to publish in our journal sharing your important research findings with the global ocean community.

Open Access: free for readers, with article processing charges (APC) paid by authors or their institutions.

High visibility: Indexed in the Science Citation Index Expanded in Web of Science, in Inspec (IET) and in Scopus.

CiteScore (2018 Scopus data): 1.76, which equals rank 30/92 in ‘Ocean Engineering’, rank 105/288 in ‘Civil and Structural Engineering’ and rank 77/203 in ‘Water Science and Technology’.

 

Guest Editor:

Prof. Dr. Manuel Martín-Martín

Earth sciences and environment

Department (University of Alicante). Campus Universitario del San Vicente del Raspeig, AP- 99, 03080 Alicante, Spain

manuel.martin.m3@gmail.com

Deadline for manuscript submissions:

10 March 2020

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