Late Miocene Sediments Research Articles

A giant crocodile from the Plio-Pleistocene of Kenya, the phylogenetic relationships of Neogene African crocodylines, and the antiquity of Crocodylus in Africa

ABSTRACT We describe a new crocodile, Crocodylus thorbjarnarsoni, sp. nov., on the basis of skulls and jaws from Pliocene and Pleistocene deposits in the Lake Turkana Basin of Kenya. The new species has a comparatively broad, deep snout and resembles an extinct horned crocodile from the Quaternary of Olduvai Gorge (C. anthropophagus), but the squamosal ‘horns’ are not as well developed. The skull table has a strongly trapezoidal outline different from those of the living Nile crocodile (C. niloticus) and crocodiles from late Miocene deposits in the Turkana Basin. The largest specimens are from animals up to 7.5 m in total length. It would have been the largest predator in its environment, and the early humans found in the same deposits were presumably part of its prey base. A phylogenetic analysis, including the new species and an improved sample of extinct crocodyline diversity, suggests a more complex phylogenetic and biogeographic history for the clade in Africa and the eastern Indian Ocean region than previously supposed. The analysis limits the known geographic and stratigraphic range of Rimasuchus lloydi, previously thought to occur throughout Africa from the early Miocene through the Pleistocene of northern Africa. Crocodylus niloticus is not known with certainty from units older than the Quaternary, and most late Miocene fossils from the Turkana Basin previously referred to C. niloticus can instead be referred to C. checchiai. The current first appearance datum for Crocodylus in Africa is approximately 7 Ma.

The Madrid Basin and the Central System: A tectonostratigraphic analysis from 2D seismic lines

Abstract Data from deep boreholes, seismic surveys, and surface geology are used to reconstruct the sedimentary infilling of the Cenozoic Madrid Basin. Eight main depositional sequences and seismic units are recognised. From the Paleogene, the latter four of these sedimentary sequences were deposited in a continental environment, under the influence of tectonic activity in the Central System, the Toledo Mountains, the Iberian Chain, and the Sierra de Altomira. The sedimentary infill shows an overall coarsening-upward trend from upper Cretaceous formations to syn-tectonic conglomerate deposits, followed by a fining-upward sequence and moderate reactivation of some faults during the late Miocene–Pliocene. The syn-tectonic sediments are Oligocene–early Miocene in age. The foredeep is oriented northeast–southwest and shows a sediment thickness of up to 3800 m in areas close to the Central System. Several types of tectonic structures are recognised, including imbricate thrust systems, thrust triangle zones, fault-propagation folds, back-thrust systems, and pop-up structures. The frontal thrusts were subjected to significant erosion, and late Miocene sediments onlap the anticlines of the onshore foreland. NW–SE-trending positive flower structures have been recognised in the eastern part of the basin. The total northwest–southeast shortening across the contact between the Madrid Basin and the Central System is approximately 5 km, of which 2–3 km occurred across the Southern Border Thrust. The simultaneous basement uplift of the Central System and the tectonic escape of the Sierra de Altomira have been interpreted as a consequence of constrictive deformation within the “Pyrenean” foreland of the Iberian microplate.

Extending the utility of artiodactyl postcrania for species-level identifications using multivariate morphometric analyses

Studies of paleoecology are most powerful when relative abundance data are available at fine taxonomic scales and large sample sizes. Postcranial elements are abundant but seldom identified to species, reducing potential sample size. We investigate whether antilocaprid astragali, abundant in the Late Miocene deposits of the Great Basin, can be identified to species, improving sample sizes. Our analysis of African and Asian bovid data from the literature suggests species should be distinguishable using astragalar dimensions. For our case study we use three species of antilocaprids, Ilingoceros alexandrae, Ilingoceros schizoceras, and Sphenophalos nevadanus from the Hemphillian (~8 Ma) Thousand Creek Fauna of northwestern Nevada. These species are diagnosed by their horncores, but previous comparisons of their dentition have shown no clear separation between the species. Our analysis of >200 antilocaprid astragali from Thousand Creek indicates there is enough variation to tentatively reject the hypothesis of only one species, but the distribution does not allow assignment of individual astragali to species. Combined with horncore morphology, our results suggest differences in male-male competition and a slight difference in body size kept the two genera out of competition while ecological similarity and/or shared ancestry created a continuous distribution of astragalar dimensions. The data cannot resolve whether I. alexandrae and I. schizoceras are distinct species. Additionally, we explored the range of effectiveness of a published discriminant function developed to derive environmental preference from African bovid astragali. Applying this discriminant function to Antilocapra proved ineffective, likely a consequence of the distinct evolutionary histories of antilocaprids and bovids.

Reply to the comment by J.P. Figueiredo & C. Hoorn

Abstract We documented and interpreted outcrops of Late Miocene sediments (upper Solimoes Formation) from the Eirunepe region (state of Amazonia), which is clearly expressed in our paper Gross et al. (2011) . We do not discuss the geological history of the entire Amazon region, neither in terms of (palaeo-)geography nor in time. Therefore, we refuse the comment of Figueiredo and Hoorn (2011) that we have drawn over-generalized conclusions, which may mislead readers.

New material of Carnivora (Mammalia) from the Late Miocene of Axios Valley, Macedonia, Greece

A new collection of carnivores from the Late Miocene deposits of Axios Valley, Macedonia, Greece was collected in 2004–2009 at the localities named Xirochori 1 (XIR) and Ravin de la Pluie (RPl), dated to the Late Vallesian (MN 10), as well as at Ravin des Zouaves 5 (RZO), dated to the Early Turolian (MN 11). The studied material is described and compared morphologically and biometrically with other materials from Greece and its neighboring area. The following species are determined: XIR: Dinocrocuta sp.; RPl: Eomellivora wimani, Adcrocuta eximia leptoryncha, ?Hyaenictis sp., Metailurus parvulus; RZO: Plioviverrops orbignyi, Machairodus giganteus. This collection is interesting because it includes the upper deciduous dentition of A. eximia and Dinocrocuta, which are only known from limited material until now, especially the latter taxon. E. wimani is recognized for the first time in Greece and the Balkans, while M. parvulus is identified for the first time in the Vallesian of Greece. The possible presence of Hyaenictis in RPl is the first indication of its presence in the Vallesian. The guild structure diagrams of the carnivore fauna from the three studied localities provide some indications of their palaeoenvironment, which fits quite well with the results of previous studies on the palaeoenvironments of these localities and of the wider Eastern Mediterranean region.

Tupaiine tree shrews (Scandentia, Mammalia) from the Yuanmou Lufengpithecus locality of Yunnan, China

Tree shrew fossils are extremely rare. Here, we report two new tupaiine tree shrews, Prodendrogale engesseri sp. nov. and Tupaia storchi sp. nov., discovered from the late Miocene deposits of Yuanmou Lufengpithecus locality of Yunnan Province in China. P. engesseri is very close to the slightly younger species P. yunnanica Qiu (Vertebrata PalAsiatica, 24: 308–319, 1986) from the Lufeng Lufengpithecus locality of Yunnan Province. Relatively lower crowns and less trenchant tooth cusps of P. engesseri show that P. engesseri is more primitive than P. yunnanica. Tupaia storchi is a species larger than Palaeotupaia sivalicus Chopra and Vasishat, 1979, T. minor Günther, 1876 and T. javanica Horsfield, 1822, but smaller than all the other extant species of Tupaia and T. miocenica Mein and Ginsburg, 1997. The mesiobuccal side of the lower molar of this species develops a very strong cingulid. It should be interpreted as a primitive condition. Discovery of diverse tree shrew fossils in Yunnan suggests that multiple evolutionary lineages of tree shrews must have coexisted in a very large area in East Asia.

Fagaceae from the early Oligocene of Central Europe: Persisting new world and emerging old world biogeographic links

Dispersed pollen from phosphoritic nodules of early Oligocene age from Cospuden (Rupelian, Saxony, Central Europe) comprises six distinct types of Fagaceae belonging to four to five genera, three of which belong to extinct lineages. Eotrigonobalanus and Trigonobalanopsis have stratigraphic ranges from the Eocene to the Miocene and the Pliocene, respectively, and an unassigned fagaceous pollen type might belong to a lineage related to the middle to late Oligocene Amentoplexipollenites from North America. Also pollen of Eotrigonobalanus from Cospuden is strikingly similar to pollen attached to staminate catkins in middle to late Oligocene sediments from the North American Gulf Coastal Plain. Both types of pollen co-occur with foliage of the Eotrigonobalanus type ( Dryophyllum, Berryophyllum). Furthermore, cupules and fruits from the middle Eocene to lower Miocene in Europe ( Trigonobalanus andreanszkyi Mai) and the Oligocene of the Gulf Coastal Plain are structurally similar. This suggests an intercontinental distribution of this extinct lineage of Fagaceae with migration across the North Atlantic. Trigonobalanopsis is endemic during the Cenozoic in Europe. Although present in late Miocene sediments of Iceland it has not been reported from North America. The extant genera Fagus and Quercus are not known prior to the Eocene. The unequivocal presence of Fagus in Rupelian sediments of Central Europe is the oldest record of the genus in western Eurasia. Fagus migrated to Europe from the east (Central and East Asia) after the closure of the Turgai Seaway. Pollen belonging to Quercus Group Ilex also marks the oldest record for Europe. Today, this group of oaks is endemic to Eurasia with isolated occurrences in the Mediterranean, the Himalayas, and East Asia. It is unclear, whether the group originated in Europe or East Asia. Pollen belonging to either Quercus Group Quercus or Group Lobatae (white and red oaks) dates back at least to the Eocene in Europe (Baltic Amber). Based on systematic affinities of leaves from late Oligocene sediments in Saxony, pollen from Cospuden with the distinctive features of these infrageneric groups may represent Group Lobatae (red oaks). This group is at present confined to North America, but appears to be represented in the fossil record of East Asia and Europe.

Study of fossil wood from the Middle–Late Miocene sediments of Dhemaji and Lakhimpur districts of Assam, India and its palaeoecological and palaeophytogeographical implications

In order to reconstruct the palaeoclimate, a number of fossil wood pieces were collected and investigated from two new fossil localities situated in the Dhemaji and Lakhimpur districts of Assam. They belong to the Tipam Group considered to be of Middle–Late Miocene in age and show affinities with Gluta (Anacardiaceae), Bischofia (Euphorbiaceae), Bauhinia, Cynometra, Copaifera-Detarium-Sindora, Millettia-Pongamia ,a ndAfzelia-Intsia (Fabaceae). The flora also records a new species of Bauhinia named Bauhinia miocenica sp. nov. The assemblage indicates a warm and humid climate in the region during the deposition of the sediments. The occurrence of some southeast Asian elements in the fossil flora indicates that an exchange of floral elements took place between India and southeast Asia during the Miocene.

Iblean diatremes 3: volcanic processes on a Miocene carbonate platform (Iblean Mountains, SE-Sicily): a comparison of deep vs. shallow marine eruptive processes

Evolution and magma fragmentation processes of two contrasting, well-exposed diatreme complexes interbedded with Late Miocene calcareous marine sediments in distinct sedimentary environments of a carbonate platform (Iblean Plateau, Sicily) are compared with each other. The nephelinitic Cozzo Molino diatreme (CMD) to the east developed in shallow water (0–80 m water depth); the alkali basaltic Valle Guffari seamount (VGS) to the west grew on a deeper water carbonate ramp (150–200 m water depth). We focus on the dominant boundary conditions inferred to have governed depth of magma fragmentation and subaqueous emplacement mechanisms: water depth, physical nature of host rocks, magma composition, and inferred differences in initial volatile concentrations. There are gross similarities in the composition of the two moderately evolved magmas. The low-viscosity magmas in both diatremes were laden with xenoliths originating from mantle to lower crustal sites. Although similar, the eastern shallow water CMD was likely more volatile-rich, with magma fragmented prior to reaching the surface and the surrounding tephra cone was partly emergent. The eruptions of the entirely submarine VGS diatreme complex in the deeper water environment were dominated by interaction of soft sediment and alkali basaltic magma or a pre-fragmented volatile-particle mixture. Eruption columns were, thus, strongly damped and the submarine complex never pierced the water surface.

Middle Miocene Uruguaytheriinae (Mammalia, Astrapotheria) from Peruvian Amazonia and a review of the astrapotheriid fossil record in northern South America

ABSTRACT Five mandibular and dental specimens referred to the extinct South American ungulate clade Astrapotheria are described. They originate from late middle Miocene deposits of the Ipururo Formation in the Rio Inuya-Rio Mapuya area, Peruvian Amazonia. The first Peruvian astrapothere remains unearthed in a controlled stratigraphical context reveal the co-occurrence of the uruguaytheriine astrapotheriids Xenastrapotherium sp. and Granastrapotherium cf. snorki. Bispecific uruguaytheriine assemblages were so far restricted to the early Miocene of Venezuela and the late middle Miocene of Colombia. The Fitzcarrald local fauna, including the uruguaytheriines described here, recalls unequivocally the Xenastrapotherium kraglievichi Cabrera, 1929-Granastrapotherium snorki assemblage, which characterizes the 13.6–12.76 Ma interval in the Honda Group of La Venta area, Colombia. The spatio-temporal distribution of low-latitude astrapotheriids (< 30°S) is then reviewed, illustrated, and further detailed in both str...

Magnetic fabric of Late Miocene clay-rich sediments from the southern Pannonian basin

The magnetic fabric of Late Miocene sediments from the southern Pannonian basin was studied on oriented samples collected from 19 geographically distributed localities. All of them are characterized by near-horizontal magnetic foliation plane after tilt correction, indicating weak deformation. Well-developed lineations were observed for 16 localities, which are interpreted as due to compressional/transpressional deformation, except from three localities, where the fabric must have been formed in an extensional setting. Comparison between the orientation of the map-scale folds and faults and magnetic lineation directions shows that magnetic lineation is either related to NNE-SSW directed compression, leading to the formation of folds or it can be connected to NW–SE or NNE-SSW trending dextral faults.

Hammer-toothed ‘marsupial skinks' from the Australian Cenozoic

Extinct species of Malleodectes gen. nov. from Middle to Late Miocene deposits of the Riversleigh World Heritage Area, northwestern Queensland, Australia are enigmatic, highly specialized, probably snail-eating marsupials. Dentally, they closely resemble a bizarre group of living heterodont, wet forest scincid lizards from Australia (Cyclodomorphus) that may well have outcompeted them as snail-eaters when the closed forests of central Australia began to decline. Although there are scincids known from the same Miocene deposits at Riversleigh, these are relatively plesiomorphic, generalized feeders. This appears to be the most striking example known of dental convergence and possible competition between a mammal and a lizard, which in the long run worked out better for the lizards.

Climate-driven rampant speciation of the Cape flora

Aim To test whether the radiation of the extremely rich Cape flora is correlated with marine-driven climate change. Location Middle to Late Miocene in the south-east Atlantic and the Benguela Upwelling System (BUS) off the west coast of South Africa. Methods We studied the palynology of the thoroughly dated Middle to Late Miocene sediments of Ocean Drilling Program (ODP) Site 1085 retrieved from the Atlantic off the mouth of the Orange River. Both marine upwelling and terrestrial input are recorded at this site, which allows a direct correlation between changes in the terrestrial flora and the marine BUS in the south-east Atlantic. Results Pollen types from plants of tropical affinity disappeared, and those from the Cape flora gradually increased, between 10 and 6 Ma. Our data corroborate the inferred dating of the diversification in Aizoaceae c. 8 Ma. Main conclusions Inferred vegetation changes for the Late Miocene south-western African coast are the disappearance of Podocarpus-dominated Afromontane forests, and a change in the vegetation of the coastal plain from tropical grassland and thicket to semi-arid succulent vegetation. These changes are indicative of an increased summer drought, and are in step with the development of the southern BUS. They pre-date the Pliocene uplift of the East African escarpment, suggesting that this did not play a role in stimulating vegetation change. Some Fynbos elements were present throughout the recorded period (from 11 Ma), suggesting that at least some elements of this vegetation were already in place during the onset of the BUS. This is consistent with a marine-driven climate change in south-western Africa triggering substantial radiation in the terrestrial flora, especially in the Aizoaceae.

Rapid extensive erosion of the North Alpine foreland basin at 5-4 Ma

An extensive low-temperature thermochronology study of the Swiss part of the North Alpine Foreland Basin has been conducted with the aim of deciphering the late Neogene basin development. Apatite fission-track (AFT) ages from wells located in the distal and weakly deformed Plateau Molasse reveal rapid, km-scale erosion with an onset in early Pliocene times. The distribution of erosion implies that there was a strong gradient in late Miocene deposition rates along the strike of the basin, with an increase towards the northeast. Additionally, renewed tectonic activity and km-scale out-of-sequence thrusting during Plio-Pleistocene times is indicated by AFT data from wells within the thrusted, proximal Subalpine Molasse. Several different mechanisms driving late Neogene basin erosion and accelerated erosional discharge from the European Alps have been considered in the literature. Based on our AFT results, we reevaluate previously published hypotheses, and suggest that a change in climate and/or drainage reorganisation coincided and possibly interacted with preexisting tectonic and geodynamic forces in the Alpine region.

Giants in a minute catfish genus: first description of fossil Mochokus (Siluriformes, Mochokidae) in the Late Miocene of Chad, including M. Gigas, sp. nov.

ABSTRACT The first Mochokus (Siluriformes, Mochokidae) remains of the fossil record are described, including a new species based on a sub-complete neurocranium discovered in the Late Miocene deposits of Toros-Menalla, Chad, Central Africa, dated to 7.0 Ma. Mochokus gigas, sp. nov., is the first fossil species described for the family Mochokidae, which is the largest family of African catfishes. The description is based on the comparison with the two living species of the genus, M. niloticus and M. brevis. Mochokus gigas, sp. nov., is a very large species presenting original features, notably on the pectoral spines and on the anterior part of the neurocranium. One of the apomorphies characterizing the modern genus Mochokus is found on the fossil: the root of the mesocoracoid arch is located on the posterior side of the vertical lamina of the coracoid and lacks any dorsally directed prominence. Several other Mochokus fossil remains, including nuchal plates, cleithra, and dorsal spines, are described and attributed to Mochokus, sp. indet., or Mochokus sp. Finally, and on the basis of preliminary observations of the fossil fish assemblages from different sites of Toros-Menalla, the lack of Mochokus fossil remains is discussed.

Geological map of the Pliocene succession of the Northern Siena Basin (Tuscany, Italy)

Please click here to download the map associated with this article. The late Miocene-Pliocene sedimentary fill of the Siena Basin (Tuscany, Italy) consists dominantly of clastics and has internal architecture that reflects the interplay of tectonics, relative sea-level changes and climate variations. Pliocene sediments are extensively exposed and overlay both late Miocene deposits and pre-Neogene bedrock. Specifically, Pliocene basin margin sediments consist largely of sand with gravel and mud intercalations, deposited mainly in nearshore settings with minor fluvial depositional episodes. They grade basinward to dominantly offshore fines with intervening turbiditic sand bodies. New fieldwork revealed that basin margin deposits, notwithstanding lithologically rather homogeneous, are made of a variety of sedimentary facies and bear several unconformities. They have been traditionally described and mapped using lithostratigraphic criteria, that have proven to be unfit to represent such complex stratigraphic architectures. The aim of this paper is to describe the allostratigraphic architecture of the Pliocene deposits exposed in a marginal key-area (45 km) of the northern Siena Basin by means of a 1:10,000 scale geological map. The recognized succession of allostratigraphic units and their bounding discontinuities, along with new biostratigraphic data from calcareous plankton, provides new insights into the geological history of the Siena Basin and represents valuable constraints for long-distance correlation.

Rudabànya: Taphonomic analysis of a fossil hominid site from Hungary

The late Miocene deposits at Rudabànya, Hungary, were laid down in a shallow valley sloping westwards from a range of hills and opening out into the Pannonian Lake. Rise and fall of lake level gave rise to varying conditions, from dry land with soil formation to swamp and lake. The stratigraphic and palaeontological succession has been investigated at one of the sites, Rudabànya 2, where two cycles of deposition and erosion are represented, with soil formation, swamp conditions with lignite formation, and periods of extended high lake level succeeding each other. Both mammal and plant fossils are present at several levels. Taphonomic modifications in the Rudabànya 2 vertebrate faunas include losses of skeletal elements through carnivore selection, fluvial sorting at some levels, and post-depositional destruction by leaching and/or acid soils. The lowest level, the lower lignite, has few fossils. The fossil mammals from the level above, the grey marl, are the least modified but they are mixed with abraded, probably allochthonous, bone fragments and more complete specimens resulting from near-lake deaths. Modifications of bones by carnivores are indicated, but the specimens were too broken post-depositionally for the impact of the carnivores to be assessed. Carnivore action is also indicated for the fauna of the black clay which formed on the surface of the grey marl. The fauna consists of relatively abundant small mammals and the primates Anapithecus hernyaki and Dryopithecus hungaricus, with the latter much less common. The predator accumulating the smaller species was probably a viverrid. The red marl fauna is a transported assemblage from higher up the valley with the fossils extremely fragmentary and abraded and few identifiable specimens, almost all of which are teeth. The black mud fauna is also probably a transported assemblage, lower energy than the red marl environment, and the bones are much modified subsequently by acid corrosion similar to that seen today in bone preserved in peat bogs. Dryopithecus is a major constituent of the fauna, with Anapithecus less common. D. hungaricus is thus associated more strongly with swamp forest and shallow riverine conditions with low energy movement of water, and A. hernyaki is associated with lake shore (probably forest) conditions, accumulating in lake sediments and lake-flat sediments. The palaeoecology of the area as a whole, based on the associated flora and fauna, is a combination of swamp forest, lake shore forest and open mud flats.

Late Miocene continental biota in Northeastern Patagonia (Península Valdés, Chubut, Argentina)

A new vertebrate faunal assemblage was recently discovered from the uppermost part of the late Miocene Puerto Madryn Formation. These deposits crop out along the southwestern coast of the Península Valdés area near Punta Delgada (Chubut Province, Argentina). The exhumed vertebrate fauna includes a range of fish, bird and mammal taxa, of which the latter are most varied and abundant. The new findings represent the first record of continental fossil vertebrates in the Puerto Madryn Formation and this is the first assemblage of late Miocene continental vertebrates recorded to the south of Río Negro Province. It also includes the southernmost record of Hydrochoeridae rodents, Dendrocygninae birds and Loricariidae fishes. The mammals suggest that the fossil-bearing sediments are Huayquerian in age. The climate during the accumulation of late Miocene deposits in this region is inferred to have been warmer and seasonally drier than that of today.

A new genus and species of Mylodontidae (Mammalia: Xenarthra) from the late Miocene of southern Uruguay, with comments on the systematics of the Mylodontinae

ABSTRACT New associated cranial and postcranial remains of a new genus and species of Mylodontinae: Lestobradys sprechmanni, gen. et. sp. nov (Mammalia: Xenarthra), were found on the coast of Kiyú beach (San José, southern Uruguay). The specimens described are from the late Miocene (Huayquerian SALMA) sediments of Camacho Formation. The mandibular configuration of this new taxon differs from all well-known members of the family in presenting a first alveolus strongly projected toward the labial region that is separated from the rest of the alveoli of the dental series by a marked diastema. It additionally differs in its combination of a subtriangular second alveolus, subquadrangular third alveolus, and a bilobed last alveolus. An incomplete skull, three thoracic vertebrae, and two caudal vertebrae were associated with the mandibular remains. We also refer a complete and well-preserved right astragalus to the new species. Aspects of the history, systematics, and taxonomy of the Mylodontidae and their proposed subfamilies are discussed.

Micropaleontology and paleoecology of the Neogene sediments in the Adana Basin (South of Turkey)

This paper analyses the stratigraphical features and fossil associations (ostracod and planktonic foraminifer) of the late Miocene deposits in the Adana Basin. In this research, numerous samples were collected from the sediments, both below and above the Messinian evaporitic layers which cropped out in the western and middle part of the Adana Basin, due to paleoenvironmental changes during the Messinian salinity crisis. The fine-grained sediments below the gypsum layers surrounding Topçu and Karayayla villages located in the western part of the Basin are sterile. Nodular anhydrite and enterolithic structures are well developed in these selenitic gypsum layers, which are supposed to represent a sabkha environmental condition. In the middle part of the Adana Basin, some re-sediment detritic gypsum deposits cropped out around Semiramis village houses. The lithological characteristics and faunal assemblages of the sediments both below and above these evaporites are more or less similar to each other. Fossil fauna (ostracod and planktonic foraminifera) demonstrate that these sediments are not older than latest Tortonian, as suggested by the presence of Neogloboquadrina humerosa, and not younger than earliest Messinian, as suggested by the last occurrence of Globigerinoides bulloideus. Similar planktonic assemblages were found in the drill log bored east of the Adana Basin, where there was no evaporitic occurrence. Both the planktonic species and the presence of Globorotalia suterae (from 7.81 Ma to 7.24 Ma) point that also these fine granied sediments a late Tortonian-early Messinian in age. The quantity of kaolinite recorded is relatively higher in the Tortonian-early Messinian than in the late Messinian sediments. All data show that, during the latest Tortonian-earliest Messinian time interval, the area was characterised by shallow marine environments and humid climatic conditions.