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In the ensemble of theropod footprints from the Imilchil macrosite, a group of small size separated from the rest is distinguished. We had detected this grouping in other sites studied by our team in La Rioja and in the work of drawing up scatter plots and frequency histograms of the measurements, on a global scale, of the length and width of the theropod footprints (these data are available on request from Farlow [ farlow@pfw.edu ]). We analyze the particular grouping of small footprints, providing the study of the theropod footprint measurements of 14 new sites with dinosaur footprints in Imilchil and the graphical representation (frequency histograms and scatter plots) of the global data. The work has been done by projecting and comparing the length and width measurements of the Imilchil footprints and the global ones of what we call circumscribed geographical environments (TGC or Temporal Geographical Circumscriptions [cf. Mínguez Ceniceros et al., 2022]). The ichnotaxonomic study of the footprints referred to in this work can be found in Masrour et al., (2023). Finally we interpret the position of maxima and minima in the frequency diagrams, both of Imilchil, and of the other areas in which Farlow has found records (up to the year 2022). • The Imilchil site has shown that theropod tracks, projected according to their length, are distributed in separate groups. One of the separate groups contains very small and small footprints. Based on the ichnological data of Farlow, we have projected the theropod footprint data from the world's sites by size. It is observed that this distribution is repeated on a global scale and that certains small footprints are scarce. The causes of this absence may be several. On the one hand, a combination of the presence of small adult and senil dinosaurs. On the other hand, a change in ONS for dinosaurs that in the adult state have medium and larger-sized footprints. [ABSTRACT FROM AUTHOR]

Detailed study of field sections and extensive ammonite collection allowed to specify the sedimentary evolution and age of the Albian series of the Western Atlas (Morocco). After a significant hiatus of earliest Albian age, the Albian transgression began in the late Douvilleiceras leightonense Zone with partly clastic deposits. A transgressive pulse gave way to clayey marl deposits (Douvilleiceras mammillatum Zone), which evolved upward to partly carbonate, laminated deposits of late early Albian to earliest middle Albian age (Lyelliceras pseudolyelli to early Lyelliceras lyelli zones). A major hiatus that encompassed most of the middle Albian, was followed by a new transgression marked first by sandy deposits (Dipoloceras cristatum and Pervinquiria pricei zones), and then by clayey marl and limestone nodules (Pervinquieria inflata Zone). A sharp sea level fall (late Pervinquieria inflata to early Pervinquieria fallax zones) led to the development of a shallow marine carbonate shelf (Kechoula Formation). A last transgressive pulse allowed deposition of outer shelf clayey marls (Pervinquieria rostrata to Arrhaphoceras briacensis (?) zones), interrupted near the Albian-Cenomanian boundary by a sea level fall and hiatus. Anoxic to disoxic conditions are recorded in the latest early Albian and the late Albian, which correlate with the Leenhardt and Breistroffer levels, respectively. Correlations with Albian successions in North Africa and southern Europe suggest a mainly eustatic origin for the most important sedimentary discontinuities, although the late Albian sea-level drop may be tectonically enhanced. [ABSTRACT FROM AUTHOR]

Aptian to early Albian times were marked by various geodynamic and paleoenvironmental events such as large igneous province volcanism, perturbations of climate and the carbon cycle, and sea-level changes. The Essaouira-Agadir basin (EAB), located on the Atlantic passive margin of Morocco, offers good and fossiliferous exposures of the Aptian–Albian sedimentary series. A detailed analysis of this succession made it possible to establish a biostratigraphic framework. The identification of discontinuities allowed to define eight depositional sequences. As most of them are correlatable with depositional sequences of other Tethyan areas, they suggest that eustacy was the main parameter controlling sedimentation. The analysis of sedimentary facies and nannofossil assemblages provides information on paleoenvironmental changes. Sedimentation in the EAB evolved from a very low energy, carbonate ramp in the early Aptian to a low energy, slightly deeper, mixed carbonate-clastic ramp in the early Albian. This change occurred along with an increase of clastic input, a change from oligotrophic to mesotrophic faunal assemblages, and a decrease of sea-surface temperatures. The occurrence of current sedimentary features, sporadic dysaerobic deposits and local phosphatic and glauconitic crusts suggests that upwelling currents were significant during this period. Paleogeographic and isopach maps support a transgressive trend in the late Aptian and early Albian, and unravel subsidence anomalies suggesting mild halokinetic movements during Aptian‒early Albian times. [ABSTRACT FROM AUTHOR]

Abstract The Barremian-Aptian interval is considered a turning point in the extensional evolution of the passive Atlantic margin of Morocco. The biostratigraphy and sedimentology study of the coarse-grained clastic deposits of the Essaouira-Agadir Basin (Bouzergoun Fm) indicates that they are entirely late Barremian (Sartousiana p.p. to Sarasini p.p. Zones) and suggests that most of them were deposited in a shallow marine environment, locally impacted by substantial fluvial influences. Facies evolution and the identification of discontinuity surfaces subdivide the unit into seven depositional sequences, two of which are marked by coarse-grained deposits and numerous indications of synsedimentary instability, and are interpreted as tectonically enhanced. These late Barremian tectonic events are interpreted as related to the abrupt uplift of the West Moroccan Arch, a long-lived, NNE-trending positive structure, located east of the Essaouira-Agadir Basin. [ABSTRACT FROM AUTHOR]

Abstract The Essaouira-Agadir Basin (EAB) of Morocco contains the most extensive exposure of Aptian to Lower Albian strata onshore the NW African Atlantic Margin. This paper documents the first high-resolution, multi-disciplinary stratigraphic approach for the Aptian to Lower Albian on the NW African Atlantic Margin. Previous biostratigraphic work almost exclusively relied on long-distance correlation of ammonoids to the Mediterranean – Caucasian Realm. Recent biostratigraphic work has questioned some of the previous interpretations, highlighting significant faunal endemism and complications with correlation to other key Aptian sections. This study focuses on 5 key sections: Tiskatine, Id Amran, Assaka, and DSDP 416/370. Distribution of ammonoids, foraminifera, and calcareous nannofossils are reported from a bed-by-bed collection made at Tiskatine. The analysis of foraminiferal and calcareous nannofossil assemblages enable correlation to standard zonation schemes; but also highlights the urgent need of revision and future work on the integration of these schemes across disciplines. The study, further, includes δ13C carb , δ13C org , and total organic carbon (TOC) data that is compared to reference material from the Vocontian Basin. The combined litho-, bio-, chemo-, and sequence stratigraphic analysis establishes a robust chronostratigraphic framework for regional and super-regional correlations and a type section is proposed for the Aptian of NW Africa at Tiskatine. [ABSTRACT FROM AUTHOR]

This paper presents the study of 14 new sites with theropod footprints in Imilchil. The study focuses on ichnotaxonomic and extramorphological characteristics of the footprints, the analysis of their trackways, and the correlation with the descriptions of published tridactil footprints. The objective has been to provide a comparative view of theropod ichnites with the relationship between the substrate and the footprint (in the interval between its formation and its current state) and the ichnotaxonomic data. The distribution of footprints in true or real footprints (including stamps and deformed footprints), undertracks, subtracks, and eroded footprints is introduced, and the variation in their morphological characters due to preservation processes is analyzed. An exposition of the analysis of the measurements of footprints and trackways has also been made, comparing them with data obtained in two other large sites studied and known by the team (La Rioja and Iouaridène). The numerical data confirm the generality of some of the previous and little-known observations of the repetition of distributions related to the metric of dinosaur footprints and trackways. • 346 new tridactyl footprints from 14 sites of Imilchil macrosite are analyzed. The data refer to 138 biped dinosaurs • The footprints are digitigrade, tridactyl, mesaxonic, with separated and acuminate ending digits, and are assigned to theropod "like" footprints. • At Imilchil we have published sites with sauropod footprints and/or crocodile ichnites (tail traces and footprints). • The influence of the state of conservation of footprints and the relative value of metric and morphological data in the ichnotaxonomic determination of dinosaur footprints is applied. [ABSTRACT FROM AUTHOR]

A revised ammonoid biostratigraphy is presented for the Aptian of NW Africa, Essaouira-Agadir Basin ( EAB ), Morocco, based on detailed analysis of 5 key sections. A number of bio-events are documented and 26 genus and 43 species fully documented, forming the largest published Aptian ammonite collection made from NW Africa. The section at Tiskatine is documented as the type section, and 8 zones and subzones are defined, of which 5 are new. This work allows correlation of the Aptian of the EAB to the Standard Mediterranean Ammonite Scale ( SMAS ). Two main hiatuses are identified at the scale of the basin scale: a major one that includes most of the lower Aptian and the base of the upper Aptian and a second one encompass the top of the upper Aptian and the base of the lower Albian. The ammonite fauna displays a clear Tethyan palaeobiogeographic character affected by a fairly high degree of endemism at the genus and species level. The new genus and species Elsaisabellia tiskatinensis is introduced. [ABSTRACT FROM AUTHOR]

Cretaceous pterosaurs tracksites are very rare worldwide. Until now,only one African Cretaceous site withtracks of ( Agadirichnus elegans and Pteraichnus ) was known. This makes the discovery of a new outcrop in the Upper Cretaceous of Anza (Morocco) the third manifestation of this type of footprint in Africa, extending the existence of such traces from the Coniacian-Santonian to the Maastrichtian. The site contains only manus tracks, which can be explained as a result of erosion of pes prints. The lack of pes prints and the morphometric characteristics of the manus prints only allow us to relate these prints to Agadirichnus , Pteraichnus or maybe to a new ichnogenus. It is possible that the trackmakers are related to Ornithocheiroidea or Azhdarchoidea superfamilies whose fossil bones have been found from the Late Cretaceous in Morocco. [ABSTRACT FROM AUTHOR]

The Anza site shows large ichnological surfaces indicating the coexistence in the same area of different vertebrate footprints (dinosaur and pterosaur) and of different types (tridactyl and tetradactyl, semiplantigrade and rounded without digit marks) and the footprint variability of long trackways. This area may become a world reference in ichnology because it contains the second undebatable African site with Cretaceous pterosaur footprints - described in part I - and the first African site with Macropodosaurus footprints. In this work, problems related to long trackways are also analyzed, such as their sinuosity, the order-disorder of the variability (long-short) of the pace length and the difficulty of morphological classification of the theropod footprints due to their morphological variability. [ABSTRACT FROM AUTHOR]

A detailed stratigraphic analysis was carried out on Valanginian deposits of six Moroccan sections of the Essaouira-Agadir Basin (EAB, South Tethyan margin) in order to characterize the Weissert Event and propose correlations with the North Tethyan margin (south–east France Basin). The studied successions consist of alternating marlstone and limestone beds with sandy intercalations, and are well exposed and relatively rich in ammonites. Ammonite biostratigraphy and sequence stratigraphy were established for all successions, whereas calcareous nannofossil and carbon stable isotope analyses were performed for two and five sections, respectively. For each succession, an accurate ammonite zonal scheme allows to recognize the standard zonation established for the Mediterranean Province. A calcareous nannofossil zonation is provided for Zalidou and Aït Hamouch, considered as reference sections. The detailed biozonations allowed to ascribe an accurate age for most of the sedimentary discontinuities and depositional sequences identified in the EAB. East–west and north–south transects are established for the Valanginian depositional system. Despite some stratigraphic gaps, the Valanginian carbon isotope excursion (CIE) was recognized in most of the studied sections. The Moroccan successions are correlated with those of reference sections of south–east France i.e., the Vocontian Basin (Vergol-La Charce) and Provence Platform (Carajuan), using bio-sequence-chemo-stratigraphy. These inter-basin correlations allowed to evidence major "mid-Valanginian" and upper Valanginian eustatic regressions; the possible role of tectonics and glacio-eustacy is also discussed. • Integrated stratigraphy is proposed for South Tethyan Valanginian sections in Morocco. • Detailed ammonite ranges and depositional sequences are described for all sections. • Calcareous nannofossil and ammonite zonations are calibrated for two sections. • The mid–Valanginian Weissert Event is characterized through carbon isotope analyses. • Moroccan sections are correlated with reference sections of south–east France. [ABSTRACT FROM AUTHOR]

The Lower Ordovician Fezouata Konservat-Lagerstätte from southern Morocco has been one of the major palaeontological discoveries of the last decade. It provides a unique insight into one of the most critical periods in the evolution of marine life: the Cambrian–Ordovician transition. However, its potential for deciphering key trends in animal diversification was hitherto largely limited by major uncertainties concerning its stratigraphic position, age and environmental setting. Based on extensive fieldwork, fossil evidence, and facies recognition, our study provides clarification on these three crucial issues. Exceptional preservation is limited to two intervals within the Fezouata Shale. Graptolites indicate a late Tremadocian age for the Fezouata Konservat-Lagerstätte as a whole, which is supported by biostratigraphical evidence provided by acritarchs. Sedimentological features and reconstructed patterns of relative sea-level changes indicate relatively shallow-water environmental conditions, under distal storm influence, in an offshore to lower shoreface siliciclastic ramp setting. The Fezouata Biota represents a unique and exceptional window into the palaeobiodiversity in open-marine conditions, thus contrasting with the other Ordovician Konservat-Lagerstätten presently known. In our analyses of this new set of data, we pave the way for accurate temporal, faunal and environmental comparisons with other Lower Palaeozoic Konservat-Lagerstätten, and unlock the full potential of the Fezouata Biota to better understand the processes and scenarios of early animal radiations. [ABSTRACT FROM AUTHOR]

In this work we present the description and analysis of a palaeoichnological site (7.9TAG) that only contains crocodile tracks. The site contains well preserved and abundant crocodilian manus and pes prints; there are no belly and/or tail traces. The crocodyle tracks have been mapped and the biomorphic and morphometric characters of the tracks and trackways have been studied. Between the digit traces of the pes prints (not in manus prints) there is a graded depression that indicates the presence of a foot webbing. The number of crocodilian footprints (93) and trackways (8) of the site is sufficient to define, and to support with confidence the data shown in the article. As consequence a crocodiliform ichnogenus, Batrachopus has been defined, characterized by the presence of a trace of a probably interdigital membrane in the pes prints, the trace of a bulge on toe V, the lack of tail traces, and the very narrow gauge trackway. A comparative study is done with all the fossil crocodile footprints described so far. The 7.9TAG footprints printed on sediments of Middle?-Upper Jurassic age (Isli Formation) are the first Batrachopus ichnites described both from this age and in the African continent. • A new Batrachopus , crocodilian fossil print, has been described. • Webbed pes and a protrusión of toe V are two singular and differential anatomical characters. • High-walking and lack of tail marks trackways. • The only Batrachopus ichnogenus of Middle?-Upper Jurassic age. • The first mention of Batrachopus ichnogenus in the African continent. [ABSTRACT FROM AUTHOR]

The Anza tracksite, discovered in 2013, is one of several sites in the Western High Atlas of Morocco that contain well-preserved and diverse dinosaur and pterosaur trackways. The occurrence of rare tracks at Anza combined with the stratigraphic position, coastal location, and easy accessibility, have inspired the scientific community, non-governmental organizations, and local inhabitants, to increase public awareness of the scientific, geoeducational, and ichnological heritage potential of the tracksite, as well as to develop strategies for site conservation and protection. • Presents the dinosaur and pterosaur tracksite at Anza as a potential geosite. • Describes the geographic and geologic context of the Anza tracksite. • Summarizes the paleontological importance of the tracks. • Describes the educational/touristic value and protection/conservation efforts. [ABSTRACT FROM AUTHOR]

A major global marine transgression occurred during the Callovian to Early Kimmeridgian, which was interrupted locally by a hiatus during the Late Callovian to Early Oxfordian. The transgression may have been a major driver for extensive coral buildup development in the Oxfordian. The depositional hiatus may be related to a combination of eustasy, local tectonic activity and hinterland movements, highlighting the potential influence of tectonism on sedimentary evolution in sedimentary basins. Whilst a regional Late Callovian-Early Oxfordian hiatus has been recorded extensively in the Tethys realm, this study has improved the biostratigraphic and sedimentary record from Morocco, and for the first time documents the Late Callovian-Early Oxfordian depositional hiatus in the Atlantic realm. Detailed sedimentary facies analysis of Callovian to Oxfordian carbonates and siliciclastics (Ouanamane Formation) demonstrates a major transgression from continental and coastal sediments, through oolitic mid-inner ramp deposits, brachiopod-rich middle ramp deposits, and ultimately to outer ramp marls, sharply overlain by Middle Oxfordian coral buildups across the basin. Repeated hard- and firmgrounds and bioturbated bed tops highlight transgressive surfaces traceable basinwide, which suggests low sedimentation rates in the upper Ouanamane Formation. Localized siliciclastic input is evidence for episodes of erosion in the same interval. Collection of new fossil specimens (ammonites, brachiopods, echinoderms, foraminifera) and revision of existing fossil material suggest this interval corresponds to a hiatus or condensed section in the Callovian-Oxfordian transition. The uppermost part of the Ouanamane Formation is of early Middle Oxfordian age and is directly overlain by Middle Oxfordian coral buildups. Onset of buildup construction is considered synchronous based on the new biostratigraphic data. Observations in Moroco compare with the sedimentary evolution around the Tethys, and in particular with the Arabian Plate. The Callovian-Oxfordian depositional hiatus corresponds to eustatic sea level changes, which were possibly driven by global cooling, and was likely overprinted by local tectonics. • Revised biostratigraphy of the Callovian-Oxfordian succession on the Atlantic margin of Morocco. • Upper Callovian-Lower Oxfordian condensed section or hiatus, consistent with regression recognized in the Tethyan realm. • Overlying Oxfordian coral buildups have a basal Middle Oxfordian age. [ABSTRACT FROM AUTHOR]

Among the footprints found in Imilchil (Central High Atlas, Morocco) are two large ichnites that we characterize as "colossal" to distinguish them from the "giant" theropod footprints in the usage of other authors. These discoveries add to the scarce record of very large footprints, and contribute to the knowledge of the spatial-temporal distribution of such colossal footprints. We classify the sites with dinosaur tracks by their geographic location and age in Temporal Geographical Circumscriptions (TGCs) that lead to the separation of nine TGCs containing colossal theropod tracks. We analyzed the total content of described theropod footprints of the nine TGCs to relate the colossal footprint populations by size. This analysis, which extends from the Middle Jurassic to the Upper Cretaceous, distributes the colossal footprints geographically in a limited (non-random) way. As a consequence of the above, we hypothesze that their distribution may be zonal possibly due to latitude, climate or geographical barriers. localized in different TGCs according to the geological period. • Two new colossal size theropod footprints that exceed 70 cm in length from Mid-Jurassic age are described. The macro-site (Imilchil) also contains other vertebrate ichnites. • The new ichnites are digitigrade, tridactyl, mesaxonic, with strong, separated and acuminate ending digits. • These are two examples of the 26 colossal size theropod footprints cited on a global scale. • The total of colossal theropod footprints are found isolate or belong to only one trackway on a study surface (except on Ardley quarry?). • The distribution of colossal theropod footprints is not homogeneous, but is determined by space and time. So far they have only been found in 5 continental-scale territories (North America, South America, Central Asia, Europe and Morocco) but not but not all in the same time period (Middle Jurassic, Upper Jurassic, Lower Cretaceous, Upper Cretaceous). [ABSTRACT FROM AUTHOR]

The extensive exposures of Mesozoic rocks along the Atlantic Moroccan margin can offer the best and the most continuous record of Mesozoic sediments and Upper Jurassic – Lower Cretaceous deposits along the Atlantic margin. This study reports the results of high resolution sampling and sedimentary logging of key outcrops to allow for ammonite, calpionellid and nannofossil biostratigraphy, in order to build a new integrated biostratigraphic chart for the uppermost Tithonian to the lowermost upper Barremian. This has been correlated to the offshore record (DSDP Sites 370/416A), which has also been redated using newly described calcareous nannofossil assemblages that confirm a thick and previously undescribed upper Tithonian through Berriasian succession. Calpionellid assemblages, although sparse, show affinities to the Mediterranean Tethys assemblages. Ammonites also show affinities to the Mediterranean Tethys taxa, but the identification of two new species points to periods of endemism during the lower Hauterivian. Calcareous nannofossils show varied affinities; to the North Atlantic Tethys and Mediterranean Tethyan Realms, the Cental Atlantic and short, but distinct cold-water Boreal Realm exchanges during the Berriasian, lower Valanginian and upper Hauterivian which have necessitated the development of a local EAB nannofossil zonation. The faunal affinities, local morphological variations and periods of faunal endemism are attributed to relative sea level changes which influenced the connection between the Essaouira-Agadir Basin (EAB), Central Atlantic and the western Tethyan Realm. A major sedimentary hiatus in the middle part of the Berriasian is recognised in the studied sections based on the biostratigraphy. This is interpreted to record a middle Berriasian unconformity that can be correlated both regionally and globally, due to an important period of tectonic activity associated with the break-up stage of the Atlantic. This new biostratigraphy builds on recent published studies that have focused on a high resolution integrated stratigraphic framework for the upper Barremian - lower Albian interval (Lower Cretaceous) in the Essaouira-Agadir Basin of Morocco. • New data on Lower Cretaceous ammonites, nannofossils and calpionellids. • Proposition of a new age biozonation chart for the Moroccan Atlantic margin. • Affinity of Lower Cretaceous Morocco with Tethyan and North Atlantic. • Endemism of some early Hauterivian ammonites onshore Morocco. • Identification of middle Berriasian hiatus, likely related to central Atlantic rift. [ABSTRACT FROM AUTHOR]

Oxfordian (Upper Jurassic) coral buildups developed widely in Tethys and Atlantic realms, during a time when paleoclimate potentially swung between greenhouse climate and cold snaps. Buildups were constructed by platy and branching corals, sponges and microbialites. Although their initiation is commonly linked to the Upper Jurassic global transgression, a number of global and local factors may have influenced buildup growth and demise (e.g. climate, shelf geometry, detrital input). Extensive outcrops of Oxfordian buildups in Morocco provide an opportunity to investigate the relationship between external drivers and buildup fauna and architecture. Here we show that the interplay of local accommodation changes, rising sea water temperature, and increasing pCO 2 linked to the onset of the Middle Oxfordian global transgression were the main drivers for buildup initiation, which was synchronous across the basin. The demise of the coral buildups in Morocco was linked to a regression, dated no later than Upper Oxfordian, the establishment of partly evaporitic conditions across the basin, and to localized influx of coarse-grained siliciclastics, the latter likely driven by synsedimentary tectonic activity. Serial logged sections, outcrop panoramas and detailed facies analysis show that low-relief deeper-water buildups of Dimorpharaea platy corals evolved into higher-relief diversified buildups where shallower-water reworking produced coral rubble and large clinoforms. Buildup diachronicity is apparent, with younger coral bioherms growing in the depressions created between the initial bioherms. Size of buildups ranges from 2 m wide and 0.5 m thick, to 700 m wide and 80 m thick. The outcrops provide constraints on geobody architecture and heterogeneity in the subsurface of Morocco and North America, where facies-controlled dolomitization of high-energy buildup and clinoform facies is a main driver for porosity development. • Coral buildups started to develop synchronously in the Middle Oxfordian. • Evolution from deeper-water platy corals to diverse coral fauna in shallow water. • Buildups controlled by global and local factors: transgression-regression, temperature, pCO 2. • Complex internal architecture serves as analog for subsurface geobodies. [ABSTRACT FROM AUTHOR]

The Chaara cave is a natural karst cavity, located in the Middle Atlas of Morocco, shaped by water over millions of years. It is an active underground river, containing several galleries spread over two floors. The exploration of this cave led to the discovery of a teleosauroid crocodylomorph at the level of the dolomitic limestone of the earliest Jurassic (Hettangian-Sinemurian). A detailed paleontological study of the specimen's skull and nested mandible was carried out based on combinations of key morphological characteristics, but to the material does not allow an advanced assignment the Moroccan specimen to a genus level. A geological, topographical, and photogrammetric study was also carried out for the development of this discovery, which is a first in the region. A 3D model of the findings was made to reconstruct this finding. The extraction of the fossil is not possible, a molding was made to keep its imprint and allow its development as a paleontological heritage. Most known teleosauroids have been recovered from Europe, and they are particularly rare outside of Europe. In Africa, they are known from several localities in Tunisia, Ethiopia, Morocco and Madagascar. Most of the remains are fragmentary and only three species have been named , Machimosaurus rex , Machimosaurus nowackianus and Steneosaurus baroni. The temporal and geographical appearance of the first thalattosuchian in Africa remains highly discussed and not well understood thus, the discovery of new remains in Morocco in the dolomitic limestone of the earliest Jurassic is of great interest, as it represents the oldest known African thalattosuchian. It demonstrates that the geographical origin of thalattosuchians cannot currently be assessed because they were widely distributed as soon as the earliest Jurassic. • Discovery of the Moroccan Teleosauroid and its Lower Liassic age. • Geological, topographical, and photogrammetric study. • Paleontological study of the skull and mandible of the teleosauroid. • Paleo geographical distribution of thalattosuchians in the lower Lias. • Natural paleontological heritage of Tazzeka National Park. [ABSTRACT FROM AUTHOR]

The present study evaluates a methodological workflow that could identify dinosaur tracks and trackways more comprehensively at outcrop scale. The approach described here is based both on 3D modelling by photogrammetry at different resolutions, and on suitably processed digital elevation models (DEMs). The ichnosite of Anza, Morocco, was chosen to demonstrate the efficiency of the proposed pipeline, because 323 dinosaur and pterosaur tracks discovered there have already been published. One subsector containing 89 tracks, identified in the two companion works that followed a traditional approach, was selected and divided into four subzones. By combining different DEM processes (hill-shade, slope, sky-view factor, and positive openness), almost twice as many tracks (175 vs 89) are now identified in these subzones. However, the improvement is not homogeneous. In the first subzone, the previous works reported 25 tracks vs. 22 with the 3D modelling techniques used here, whereas results for the second and third subzones show considerable improvement with 3D (21 vs 38 tracks and 42 vs 81 tracks, respectively). The enhancement is even more dramatic for the fourth subzone, where 34 new tracks are now identified, whereas with the traditional approach, only one track was previously reported. It is likely that such improvements depend on several factors, i.e. the surface conditions of the rocks (e.g. irregularities, cracking, etc.), and on the preservation state and depth of the tracks. Morphometric measurements of tracks and trackways obtained from 3D models are very similar to those derived from traditional fieldwork methods. The digital approach can be applied rapidly at different resolutions, but the models acquired with the pole-mounted camera provide a good compromise, with a resolution high enough (~2 mm/pix) to spot tracks, while respecting computational constraints. Once treated, DEMs greatly facilitate the reproduction of track outlines, drawn according to criteria defined by the operator. • Processing DEM of ichnosites may help to better identify dinosaur tracks and trackways. • Morphometric measurements of tracks can be performed from processed DEM. • At the Anza ichnosite, the proposed protocol outperforms the traditional recording method. [ABSTRACT FROM AUTHOR]