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Lower Oligocene, shallow-water carbonates of the Calcareniti di Castelgomberto formation (Monti Berici, Italy, Southern Alps) are studied in detail with respect to fabric and component distributions in order to trace paleoecological changes along a monotonous sedimentary stacking pattern. The carbonates are dominated by coralline algal rudstones wi...
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The Cretaceous-Paleogene (K/Pg) boundary in the Haymana Basin, Central Anatolia, Turkey, was delineated using planktonic foraminiferal biostratigraphy, microfacies analysis, and sequence stratigraphy. An ∼ 29 m outcrop consisting of limestone and marl was measured, and four planktonic foraminiferal biozones were identified spanning the boundary. Pl...
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... Similar conclusions were reached independently by analysing the palaeoecology of larger foraminifera and coralline algae in the nearby section of Longare, which is located some hundred meters seaward with respect to the outcrops with in situ corals at Lumignano. According to Nebelsick et al. (2013), all facies associations along this ca. 100-m-thick section were deposited within the photic zone, and should be interpreted as being formed on a homoclinal ramp rather than a rimmed shelf. ...
... The facies interfingering at Brojon can be appreciated on the three-dimensional model of Chimento et al. (2023). In the woods more to the east, coral boundstones are completely substituted by rudstones of the coralline algal lithofacies, which can be traced laterally and correspond to the Longare section of Nebelsick et al. (2013). The Longare section is thus the lateral equivalent of coral reefs at Brojon, is made mostly of the coralline algal lithofacies, and lies above the Vicenza stone of the quarries of Costozza, which in turn sit on the Priabona formation. ...
... Coralline algal facies of Nebelsick et al. (2013) was also attributed to a distal portion of the inner ramp. ...
... The association of imperforate foraminifera with corallinaceae (red algae) indicates a high-energy environment with seagrass meadows (Pomar, 2001;Pomar et al., 2017). In addition, the abundance of imperforate and perforate foraminifera as well as corallinaceae indicate an inner ramp with seagrass meadows (Pomar, 2001;Romero et al., 2002;Beavington-Penney et al., 2006;Afzal et al., 2011;Nebelsick et al., 2013). Therefore, the bioclastic corallinaceae imperforate foraminifera packstone-grainstone (MF 2) and bioclast corallinaceae imperforate and perforate foraminifera floatstone-packstone (MF 3) were deposited in a normal marine shallow water environment with seagrass meadows. ...
This research attempted to determine the depositional sequences of the Qom Formation in the Urumieh-Dokhtar arc (Ghamsar section) and Esfahan-Sirjan fore-arc (Abadeh section) sub-basins in Iran, using microfacies and microtaphofacies analyses. The authors also investigated connections between the Qom Basin and the Zagros and Paratethys basins during the Oligocene. In this regard a total of eight microfacies, two terrigenous facies, and five microtaphofacies were identified on the basis of 269 samples from the Ghamsar section and 93 samples from the Abadeh section. The studied microfacies, terrigenous facies, and microtaphofacies were deposited on a homoclinal carbonate ramp. This carbonate platform can be divided into inner, middle and outer ramp environments. On the basis of the distribution of microfacies and sequence stratigraphy studies, five third-order depositional sequences and one incomplete depositional sequence were identified in the Ghamsar section and three third-order depositional sequences in the Abadeh section. According to the distribution of microtaphofacies and palaeobathymetric studies based on Amphistegina , the energy, and depth of the Qom sea in the Ghamsar section were greater than those evidenced in the Abadeh section. The results of local fault activity in the different sub-basins of the studied sections indicate a lesser effect of global sea-level changes in the Paratethys basin. On the basis of the formation of depositional sequences in these sub-basins; and differences in the number of depositional sequences; intense local fault activity is indicated during the Chattian Age (especially in the Urumieh-Dokhtar arc sub-basin). Regional sea-level fluctuations of the south Tethyan Seaway and the Paratethys Basin controlled sea-level changes in the Chattian Age. The depositional basins of the Tethyan seaway (southern Tethyan seaway, Paratethys Basin and Qom Basin) probably were related during the Burdigalian to Langhian and the early Serravallian. The results show that, the effect of sea-level changes of the Zagros Sea on the formation of depositional sequences in the Esfahan-Sirjan fore-arc sub-basin was significant.
... The sub-microfacies F7-B displays a high density of normal marine foraminifera with a perforate wall, along with alveolinids and protected marine biota. It has a grain-dominated texture and evidence of fairweather wave action, suggesting a dynamic environment with high wave energy in a seaward carbonate shoal setting above the fairweather wave base and within the euphotic zone (Harris et al., 1997;Pomar, 2001;Brandano and Corda, 2002;Pomar et al., 2004;Boudagher-Fadel and Lokier, 2005;Bassi et al., 2009;Brandano et al., 2009aBrandano et al., , 2009bNebelsick et al., 2013;Adabi et al., 2016). ...
The Early Paleogene Tethyan domain saw the development of large platform carbonates rich in large benthic foraminifera (LBF), of which the Taleh Zang Formation in Lurestan Basin, SW Iran, represents an excellent example. The LBF assemblage is dominated by alveolinids, together with a variety of foraminiferal genera such as Nummulites, Rotalia, Sackesaria, Assilina, Operculina, and Glomalveolina. Smaller benthic foraminifera, calcareous algae, gastropods, echinoids, and bivalves constitute minor components of the carbonate. Biostratigraphy analysis of the LBF is conducted on two distinct sections of the Taleh Zang Fm. The sections referred to as TZ-1 and TZ-2 have respective thicknesses of 87 m and 132 m. This analysis has constrained the formation age to the early Ypresian within Shallow Benthic Zones (SBZs) 5–7. Facies analysis supports the major accumulation of these successions in a shallow water environment within the euphotic zone. We recognize 9 distinct facies and microfacies representing four main depositional environments including tidal flat, lagoon, bioclastic shoal, and shallow open marine. These environments are distributed along a low-angle homoclinal ramp and form the foundation of a stratigraphic interpretation characterized by intervals displaying shallowing and deepening trends. Three shallowing-upward intervals have been identified within the Taleh Zang succession. The determined intervals cannot be solely attributed to global sea level fluctuations and support a significant impact of the regional structural context resulting from collision-induced uplift and variable subsidence rates. The identified intervals exhibit local and regional correlation and compatibility on the Arabian Plate, providing robust confirmation of the significant roles played by both tectonics and eustasy at a regional scale.
... Geister and Ungaro (1977) instead did not find evidence of a true barrier reef in the Oligocene of the Berici Hills. Further studies on the paleoecology of red algae and larger foraminifera also suggested a carbonate ramp depositional environment (Bassi 2005;Nebelsick et al. 2005;2013), and using facies analysis, Pomar et al. (2017) depicted the platform as a distally steepened ramp. ...
An inventory of 32 geodiversity sites and geosites has been compiled for an area characterized by high geodiversity, which also played a role in the history of geosciences. Aspects of the geology of Lumignano and Costozza (Berici Hills, northeastern Italy) have been mentioned since the 1500 s by architects that made use of building stones quarried in the area. Later on, and until the 1900s, the site was the subject of several geological studies. Nonetheless, a modern overview of local geology is still missing because of the scarcity of modern geological literature. More critically, modern geological maps are available, which makes the task of compiling a rational inventory of geodiversity sites particularly difficult. For this reason, we produced a new geological map which served as a base for compiling an inventory of 32 geodiversity sites and geosites that were ranked according to importance on a local scale. The inventory and map were then used to make popular science products that demonstrate the applicability of the work for geotouristic purposes. The critical importance of uniform and up-to-date geological knowledge of an area for the compilation of inventories of geodiversity is discussed on the basis of this case study. In the case of Italy, where the compilation of the geological map at the scale of 1:50,000 is severely incomplete, doubts could be cast that a reliable inventory of geosites could really be realized.
... Larger benthic foraminifera are abundant biocomponents of the Paleogene shallow-marine carbonate platforms and can be found in a wide range of neritic paleoenvironments (e.g., Romero et al., 2002; Notes: P: Diameter of protoconch; D: Diameter of deuteroconch; X-value: Number of nepionic chambers following the deuteroconch; Y: Angle formed by the line conjoining the centers of the two embryonic chambers and the line passing to the center of protoconch and the apical front of the test. Bassi et al., 2007;Nebelsick et al., 2013). Generally, porcelaneous larger and smaller foraminifera dominate the assemblages between 0 and 50 m on soft substrates, while nummulitids, together with amphisteginids, are the dominant element between 50 m and 100 m depth on soft and hard bottoms (Reiss and Hottinger, 1984). ...
... Some examples from Malta Island, in the Mediterranean, show vertical and horizontal patterns (0.4 to 14 m height and up to 10 km long) of calcareous algae paleo-biostrome (Bosence and Pedley, 1982;Brandano et al., 2009) similar to the structures mapped in this study. Examples from paleo-structures in the Italian Alps show that calcareous algae facies represented a low energy and luminosity environment (Bassi, 1998;Nebelsick et al., 2013) and can represent an ancient analogue to the ones found at Santos Basin. ...
The Santos Basin mesophotic zone comprises one area of 104,915 km², occupying 78% of the entire basin. Santos Basin is one of the most under stress and sensitive marine regions in the Brazilian territory due to several major ports, Oil & Gas industry, and coastal marine environmental management areas. Scientific literature recognizes that rhodolith beds and biogenic rigid-bottom patches occur on the shelf, but because lack of high-resolution seismic data, these seabed features are not yet wholly mapped at Santos Basin. However, an unprecedented gathering of historical depth sounding points and surface sediment data collection, in conjunction with an extensive field campaign of seabed sampling and sub-bottom shallow seismic records, points out new evidence of biogenic sediment distribution reefal structures in the Santos Basin. The patches of calcareous algae crusts, terraces mounds, pinnacles, and free-living rhodolith beds compose the carbonate facies on the outer shelf. Rugged bottom relief and pinnacles up to 10 m in height correlate with carbonate gravels and sandy areas. Bioconstructions are more common northward and gradually decrease southward. Geomorphological features such as rugged bottom relief might indicate the occurrence of mesophotic bioconstructions off Paraná, and Santa Catarina State coast. The mesophotic bioconstructions have evolved through four stages: 1- LGM fully sposed shelf, 2- sea-level transgression and bioconstrutions pioneers, 3- influence of the La Plata plume at the southern sector, and 4- establishment of mud patches in the northern sector due to local input.
... facies association C1 supports an interpretation of low energy conditions and low rate of sedimentation (Nichols, 2009). The presence of type 1 and 2 rhodoliths ( Nebelsick et al., 2013), agglutinated small foraminifera such as miliolids, Soritidae and small perforate foraminifers indicate the deposition in very shallow semi-restricted settings commonly associated with euphotic seagrass meadows of inner ramp setting (Haunold et al., 1997;Halfar and Mutti, 2005;Pomar et al., 2014). The small-foraminifer assemblages point to varying salinity conditions probably related either to changing connections of the inner platform to the open ocean or to variations in runoff from the emergent land (Braga et al., 2012). ...
... Based on genetic approach (the bathymetric ranges and types of carbonate factories) introduced by Pomar (Pomar, 2001;Pomar et al., 2012) the carbonate deposits of the Mishan Formation have been deposited in a ramp type carbonate platform. The presence of benthic foraminifers such as miliolids and soritids (Archaias), molluscs and coralline red algae in rhodolith forms suggests presence of seagrass meadows in the euphotic zone of inner ramp settings (Nebelsick et al., 2013). The abundance of large benthic foraminifers with hyaline walls within micritic matrix demonstrates deposition in the meso-oligophotic zone of middle ramp setting (Pomar, 2001;Bassi et al., 2007). ...
Integrated sedimentological and petrographical analyses have been used for paleo-environmental reconstruction of mixed siliciclastic-carbonate deposits of Mishan Formation (late Burdigalian-Serravallian) in the Dezful Embayment within the Zagros foreland basin. The carbonate deposits alternated with marl layers consisting of open marine, restricted to semi-restricted subtidal lagoon and tide-related facies associations with organic buildups deposited within tropical to subtropical warm water multi-factory platform including euphotic and meso-oligophotic factories. The siliciclastic deposits comprise progradational tide-influenced delta deposits including prodelta, delta front and delta plain facies associations. The lack of wave related structures and the absence of the shelf type evidence together with tide-related deposits within the carbonate facies and prograding delta deposits indicate a tide-dominated mixed siliciclastic-carbonate homoclinal ramp with the development of organic buildups. These sediments deposited within the short-lived Tethyan seaway resulted from Middle Miocene Climate Optimum through the Zagros foreland basin. Predominant heterozoan skeletal grains and alternation of marl layers with carbonate sediments indicate high nutrient and sediment flux from adjacent highlands. Carbonate tidal deposits within the siliciclastic sediments suggest that the tidal currents have provided suitable ecological conditions for carbonate production by supplying nutrients for heterotrophic organisms and pumping clear water from the ocean. Shallowing upward trend from marine carbonates and marls to prograding siliciclastic paralic and non-marine deposits of the Mishan Formation within the studied area can be linked to the eustatic sea-level fall in response to the Middle Miocene Climate Transition which led to the closure of Tethyan seaway in the Dezful Embayment.
... Frost (1981) interpreted the Oligocene platform of the Berici Hills as having a sheltered lagoon, and a discontinuous coral reef ridge. Nebelsick et al. (2013) evidenced instead the presence of a ramp environment dominated by coralline red algae. ...
Procedeeding Book of the ProGEO SW Europe Regional Working Group. Virtual Conference on Geoconservation. March 30-31, 2022
... The well developed nummulite population marked by A and B-morphotypes (megalospheric and microspheric forms respectively, linked with the sexual evolutive stage) recognized in a packstone texture suggests an optimal habitat range at mesophotic and oligotrophic marine conditions in the middle ramp (Hottinger, 1997;Geel, 2000;Martín-Martín et al., 2020c. The "encrusting" growth of coralline algae, with flattened thalli on nummulite tests and fruticose branches observed, which indicate an environmental change from the conditions described above, mark the development of a mesotrophic maërl environment, where moderate bottom currents probably related to storm events can turn over tests to form rhodoliths (Rasser, 2000;Bassi, 2005;Nebelsick et al., 2013). The additional presence of a heterotrophic biotic assemblage (echinoid debris, small benthic foraminifers, annelids, bryozoans and ostreids) supports mesotrophic conditions (Hallock, 1988b;Hallock et al., 1991;Brasier, 1995) and does not rule out eventual nutrient input fluxes (Hallock, 1988a;Hottinger, 1997;Afzal et al., 2011). ...
The Eocene Peñicas (Almería) and Harania (Málaga) stratigraphic sections from the Malaguide Complex (Betic Cordillera, South Spain) belonging to the Mesomediterranea Microplate from the westernmost Tethys (about-30° N and 0°–5°W according to the Eocene coordinates) have been studied. The Eocene sections cover the Cuisian to middle Lutetian deposits, which show several lithofacies representing shallow marine platform realms. Based on the fossiliferous assemblage, texture and fabrics, eight microfacies related to inner to outer ramp settings were defined. In the inner ramp of the Harania section abundant colonial corals have been recognized. The Eocene deposits are arranged into a transgressive succession composed by three minor transgressive-regressive sedimentary cycles. The Eocene fossiliferous assemblage shows a mixture of photozoan (Lager Bentic Foraminifera –LBF–, green and red calcareous algae and corals) and heterotrophic (mollusks, echinoids, bryozoans, small benthic and planktic foraminifers) elements, suggesting euphotic to mesophotic conditions in oligo-mesotrophic marine warm-waters at low-middle latitudes. This assemblage indicates a transition from photozoan to heterozoan carbonates and in particular a shift towards outer marine ramp settings. During the Early Eocene, the widespread distribution of LBF leads in the Tethyan domains to disappearance or extreme reduction of coral constructions. Nevertheless, abundant corals associated to inner ramp realms have been observed in the Harania stratigraphic section indicating that corals could continue to develop in the westernmost Tethys at the transition to the Atlantic Ocean, in contrast with respect to other Tethyan sectors. Therefore, the Ypresian-Lutetian time-span is a transitional period for the global temperature during which corals locally survived only where optimal ecologic conditions occurred, preferably in marginal contexts, as it seems to have happened in the studied area.
... Porselen kavkılı büyük bentik foraminiferler fotik bölgenin üst kısmında karbonat platformları geliştirirler [13]. Kırmızı algler de fotik bölge çökellerinden kaydedilen en bol bileşenlerden biridirler [14]. Genel olarak ise birimin düşük-orta enerjili, normal tuzluluktaki sığ denizel karbonat ortamlarını yansıtmaktadır. ...
The Miocene aged carbonate deposits outcropping around the Kurtalan district of Siirt province play an important role in the geological evaluation of the region. This study is based on the evaluation of the unit, which is lenticular within the Kayabağlar Formation and discriminates as the Eskigarzan Limestone Member, in the light of paleontological and sedimentological data. Along with serial sampling from four different localities taken from the Miocene aged Eskigarzan Limestone member, apart from large benthic foraminifers such as Praebullalveolina curdica (Reichel), Sivasina egribucakensis Sirel and Özgen-Erdem, Sivasina batmanensis Sirel, Özgen-Erdem and Sinanoğlu, Androsina diyarbakirensis Sirel, Özgen-Erdem and Sinanoğlu, Cyclorbiculina minima Sirel, Özgen-Erdem and Sinanoğlu, Amphistegina cf. targioni Meneghini, Elphidium cf. crispum, Miogypsinoides sp., Rotalia sp., Sphaerogypsina sp., Operculina sp. and Victoriella sp. quite common coralline and green algae were also observed. In the light of these data, the age of the unit was determined as early-middle Miocene. These carbonates, which are widespread in the region, characterize a very shallow, sheltered and medium-low energy lagoon depositional environment.
