Jesús Reolid

Photogrammetric techniques and 3D modelling are useful tools for obtaining morphological data, such as size, volume, and surface area, in paleontological studies, and its use is becoming increasingly simple, even with common devices such as mobile phones and tablets. This work takes as an example the skull of some of the largest theropods, Allosaurus fragilis (Carnosauria, Allosauroidea), Giganotosaurus carolinii (Carnosauria, Allosauroidea) and Tyrannosaurus rex (Coelurosauria, Tyrannosauroidea), for the elaboration of 3D models with the use of different photogrammetric and laser techniques. The study confirms that Tyrannosaurus head was shorter than that of Giganotosaurus but more robust with skull length/skull width ratio for T. rex (2.42) lower than for Giganotosaurus (2.98). The skull volume/lower jaw volume is higher in Giganotosaurus (3.68) than in Tyrannosaurus (3.31) also pointing to more robust head for T. rex. In addition, the mandible of Tyrannosaurus is deeper than that of other large theropods and robust thick pachydont dentition was probably adapted to develop high bite force. These features allowed T. rex to keep large prey and bite across meat and bone equally. Giganotosaurus is hypothesized to have had powerful slicing bites, based on its ziphodont dentition, and the capacity to manipulate relatively smaller preys compared with Tyrannosaurus, as inferred from its flattened lower jaw. Allosaurus, also from clade Allosauroidea like Giganotosaurus, had a narrow skull (skull length/skull width 3.24) equipped with straight pachydont teeth. Although the Allosaurus’ mandible was adapted to slice, capture and manipulate small preys, the skull volume/lower jaw volume ratio (3.53), lower than in Giganotosaurus, confirm that probably was also prepared to support high torsional stress when attacking larger preys.

An ∼ 300 m thick succession of bioclastic limestones and marls crops out in the Sierra de Marmolance (Subbetic Domain, External Zones, Betic Cordillera, SE Spain). Assemblages of planktonic foraminifera (PF) in the marls, underlying and laterally changing to limestones, indicate a late Burdigalian–early Serravallian age for the carbonates. Outcrop-scale geometry, stratigraphic patterns, facies distribution, and biogenic components reveal that Marmolance limestones formed on a prograding ramp with depth-related facies gradients. In the late Burdigalian–Langhian, from deeper to shallower, the facies are planktonic foraminiferal packstone and marls, Nummulites packstone, Neorotalia packstone, and lepidocyclinid packstone. In the early Serravallian, Nummulites packstone is missing and Risananeiza packstone and bioclastic rudstone with siliciclastics occur shorewards of lepidocyclinid packstone. Altogether, 18 species of larger benthic foraminifera (LBF) were identified in the Marmolance succession. Among them, before the present study, Nummulites fichteli, N. vascus, N. kecskemetii, Eulepidina dilatata, Eulepidina formosoides, Nephrolepidina praemarginata, and Risananeiza crassaparies were considered exclusively Oligocene taxa, whereas Nephrolepidina morgani, N. tournoueri, Neorotalia viennoti, and Spiroclypeus sp. were supposed to disappear in the Early Miocene. In Marmolance, Nummulites vascus and N. cf. kecskemetii appear in Burdigalian and Langhian strata, whereas N. fichteli is only recorded in Langhian beds. Eulepidina dilatata, E. formosoides, Nephrolepidina morgani, N. praemarginata, N. tournoueri, N. viennoti, Risananeiza crassaparies, and Spiroclypeus sp. extend at least to the Serravallian. The presence of Nummulites in the Langhian of SE Spain partly fills the stratigraphic gap in the genus record from the end of the Oligocene to the living representatives in modern Indo-Pacific areas. These findings substantially modify the chronostratigraphic ranges and assumed diversity of Neogene LBF in the Mediterranean area.

Morphology, internal structure, and in situ facies distribution of mesophotic Halimeda bioherms from the Queensland Plateau (NE Australia) are presented based on hydroacoustic and oceanographic data, seafloor observations, and discrete sediment sampling carried out during RV SONNE cruise SO292 in 2022. Halimeda buildups consist of cone-like mounds up to 500 m in diameter and 3–10 m high, with gentle slopes (2°–5° on the top of Tregrosse Bank). Bioherms occur in water depths of 10–70 m, with most bioherm between 50 and 65 m. Their internal structure consists of aggrading low-amplitude reflections at the core of the bioherm interfingering with high-amplitude reflections to the flanks. Surface facies distribution displays one to four facies belts, from distal to proximal: Halimeda rudstone, Halimeda rudstone with living plants, Halimeda rudstone with coralgal debris, and coralgal boundstone (when present, occupied the top of the bioherms). It is proposed that the alternation of two key processes contributes to the formation of these bioherms: (1) in situ accumulation of Halimeda debris and (2) episodic dismantling of the mesophotic coralgal boundstone at the centre of the bioherm by severe storms. These storms may dismantle the mesophotic reef and export coralgal rubble to the flanks. Flanks may be recolonized by Halimeda during fair-weather periods. Due to their different geomorphic expressions, complex internal structure, and surficial facies distribution, we suggest that the buildups of the Queensland Plateau represent a new Halimeda bioherm morphotype, distinct from previously described bioherms on the adjacent Great Barrier Reef and elsewhere globally.

The export of neritic material from the top of carbonate platforms is a key process in the construction of their slopes. However, our knowledge of the supply pattern of materials from platforms is dominantly based on platforms lying in the euphotic zone during the present sea-level highstand. This is a somewhat biased perspective as through geological time not all platforms were euphotic. The Saya de Malha Bank in the Mascarene Plateau is an example of a modern mesotrophic carbonate platform and as such its flooding and export patterns differ from those of euphotic ones. Using cores collected on the western slope of the Saya de Malha Bank, we explored the export patterns of the platform since the Last Glacial Maximum. Material on the platform edge is winnowed and transported to the slope by multiple possible processes. The material on the platform is a combination of high and low Mg calcite as well as high and low Sr aragonite, integrating pelagic and neritic sources. The ratio of these constitutes varies over time with variation in the platform production capability as it flooded and drowned during the Holocene transgression. The material from the platform is transported in both confined flows, mainly during lowstands, and unconfined flows, mainly during late transgression and early highstand. In the present state of the highstand, supply may have diminished, leading to erosion of the canyon shoulders.

Changes in sea-level are linked to glacial-interglacial variability and have been claimed as the main factor controlling the production of carbonate platform factories. The Maldives archipelago (Indian Ocean), composed of two rows of atolls that enclose an inner sea, is a very sensitive region to sea-level changes. The sediments of the Inner Sea, offer an excellent study site to explore the impact of sea-level changes on carbonate platforms. Elemental geochemical composition records, obtained by X-ray fluorescence (XRF) core-scanning, from the Maldives Inner Sea (IODP Site U1467), have been used in this work to evaluate the influence of orbitally-driven sea-level fluctuations on the carbonate production and export from the neritic environment into the Maldives Inner Sea over the last 1.3 million years. High Sr aragonite-rich carbonates (HSAC) from neritic settings are deposited in the Maldives Inner Sea during sea-level highstand intervals, increasing the values of the Sr/Ca ratio. In contrast, during sea-level lowstand periods large areas of the atolls were exposed or unable to grow and the demise in the carbonate production and sediment export is reflected as low Sr/Ca values in the Inner Sea. However, we propose that sea level is not the only factor controlling the production of HSAC during sea-level highstands since several interglacial periods before and after the Mid-Brunhes event (MBE, ~430 ka) indicate high carbonate production (high Sr/Ca). The intensity of the summer monsoon and the Indian Ocean Dipole probably modulated the production at the atolls. Marine Isotope Stage 11 stands out as a period with high sea-level and rather high carbonate production in the Maldives platform. This extraordinary carbonate production in the Maldives atolls (and in other low latitude carbonate platforms) probably contributed to the Mid-Brunhes dissolution event through a strong shelf-to-basin fractionation of carbonate deposition.

During the early and middle Miocene, the Mediterranean became a restricted marginal sea with the contraction of the Mesopotamian Gateway and ultimate loss of connectivity to the Indian Ocean. Leading to the transformation of the Mediterranean into a restricted marginal marine sea . Low latitude circumglobal circulation through the basin characterized the basin for most of the Cretaceous and Paleogene. With the loss of this supply of surface and subsurface waters, dramatic changes occurred to the heat, energy, and nutrient budgets across the Mediterranean. The most affected area was the eastern basin. , As is well evidenced by the onset of sapropel formation, many other aspects of the sedimentary system changed in response to this ocean circulation rearrangement. Hemipelagic successions in southwestern Cyprus offer a window into the changes in the subsurface waters occurring in the Eastern Mediterranean through the closure of the gateway to the Indian Ocean. Dated to the late Aquitanian to the early Serravallian (22.5–14.5 Ma), this sequence is carbonate-dominated and overall continues. It exhibits sedimentation with mass transport contribution from shallow water carbonates to deeper facies. The succession exhibits fluctuation of bottom current activity, which was disrupted in the early Burdigalian by mass transports and temporarily halted during the Langhian. Phosphates are present through the entire succession, but most notably in the Langhian. Combined, these lithological characteristics indicate changes in bottom current energy and seafloor ventilation that point to two key intervals of connectivity restriction through the Mesopotamian gateway.

Sediment sampling of the seafloor, especially with a box corer, is an important aspect of marine geology and sedimentology. The sediment surface recovered by this tool, however, is of limited extend (10s of cm only) and might be disturbed thru the sampling process. The Box corer Imaging System (BOXIS) is an addon for the box corer allowing for high resolution video recording of the sampling process. It attaches to the box corer main frame and adds lights, batteries and a camera. The system can be adapted to a variety of sampling devices. Its main objective is to capture video of the sample area before and after the sampling of which images can be extracted. The recording is extracted after the sampling process, when the tool is on deck. The system is equipped with LED lights featuring a total of 7000 lumens and built-in redundancy. The separate light units are connected via cable to their corresponding battery unit featuring a custom timer and magnetic activation switch. The special camera housing features a popular action camera recording at 5.3K resolution (19.6 Mpx). The camera field of view features a wide, undistorted, unobstructed view looking down. As a benefit of the camera position, depending on visibility it is possible to gather images from up to 10 m above the seafloor conveying a broader context down to close-ups 25 cm from the seafloor. The BOXIS system is rated to a maximum operation depth of 1750 m. The BOXIS footage can be examined instantly over a wireless connection on a mobile device once the box corer is back on deck to evaluate sampling quality and support discussion and decision making on the proceeding of further sampling operations. Large batteries ensured multiple deployments in a row without service. Even in cases where the box corer does not trigger, the BOXIS provides data not only of the seafloor but also on operational problems such as sediment penetration. It is a system with a minimum of cabling, which therefore is not endangered to interact with the hoisting equipment used for lowering and lifting of the normally analog gear.The BOXIS system has been successfully deployed for the first time on FS SONNE cruise SO292 in spring 2022 to the Queensland plateau, Australia. In total we could record a total of 27 deployments without a single failure. We will present the BOXIS system based on examples from these successful deployments.

Extensive canyons, excavated into the margins of the Levant Basin during the Oligocene–Miocene, are interesting case-studies for canyon fills in carbonate settings. The carbonate Pattish Formation, developed along the margins of the pre-evaporitic Messinian Beer Sheva Canyon in Israel, was investigated using both onshore seismic imaging and field data. The canyon has three main seismic facies of fill (1) Subparallel reflections mimicking the canyon´s morphology; (2) chaotic reflections overlying the subparallel ones, and (3) sigmoidal reflections, locally with sharp edges at the canyon margins. The first seismic facies corresponds to the pelagic marls of the Bet Eshel Formation. The other two seismic facies are, respectively, equivalent to bioclastic calcarenite clinobeds with slumps and channels, and to coral–stromatolite reefs and reef slopes of the Pattish Formation observed at outcrop. There were three phases of canyon development: (1) slope incision and headward erosion due to tectonic uplift and eustatic sea-level fall during the Early Oligocene, and large slope failure during the latest Middle Miocene; (2) platform incision and connection with a fluvial system in the Late Miocene related to falling sea level and tectonic uplift; and (3) canyon filling first by pelagic marls at the centre of the canyon, followed by calcarenite clinobeds at the canyon flanks formed by gravity flows. Finally, carbonate production at the margins of the canyon resulted in reefs and associated slopes prograding towards the canyon axis. The late canyon filling phase ended with the deposition of evaporites during the Messinian Salinity Crisis.