Eocene

The Eocene was the warmest part of the Cenozoic, when warm climates extended into the Arctic, and substantive paleobotanical evidence indicates broadleaf and coniferous polar forests. Paleontological temperature proxies provide a basis for understanding Arctic early Paleogene climates; however, there is a lack of corresponding proxy data on precipitation. Both leaf physiognomic analysis and quantitative analysis of nearest living relatives of an Arctic macrofl ora indicate upper microthermal to lower mesothermal moist climates (mean annual temperature ~13–15 °C; cold month mean temperature ~4 °C; mean annual precipitation
>120 cm/yr) for Axel Heiberg Island in the middle Eocene. Leaf-size analysis of Paleocene and Eocene Arctic fl oras demonstrates high precipitation for the Paleogene western and
eastern Arctic. The predicted enormous volume of freshwater entering the Arctic Ocean as a result of northward drainage of a signifi cant region of the Northern Hemisphere under a
high-precipitation regime would have strongly affected Arctic Ocean salinity, potentially supporting Arctic Ocean Azolla blooms. High Paleogene precipitation around the Arctic Basin
is consistent with high atmospheric humidity, which would have contributed signifi cantly to polar, and global, Eocene warming.

Iron ore deposits of Franche-Comté (France)
"Iron ores are so common in the province, we can consider its territory as entirely ferruginous. It would be easier to count the places where there is no iron ore than those where we find it ." This observation extracted from 'A look at the province of Franche-Comté presented to Mr. de La Chaise by "his humble servant, Father TIBURCE ", written in 1775, reflects substantially the reality that results of research done in the field or in the bibliography regarding iron ores. Such is the geographical distribution of iron deposits that at every point of the province, ironmasters disposed of ore resources close to  their blast furnace.
Except a few veins and stockworks associated with paleozoic basement of the southern Vosges, most of Franche-Comté iron ores are either marine jurassic and cretaceous deposits (domerian, toarcian, aalenian, callovian, oxfordian and valanginian oolitic iron deposits) or deposits formed by weathering, intact or reworked, (eocene and plio-pleistocene pisolitic iron deposits and ferricrusts).

The biodiversity of early Eocene cerithioidean gastropods from a marine littoral environment, including mangroves with Nypa palms, is documented from the Figols group (FG) and the overlying Castigaleu group (CG), of the Ager and the Tremp-Graus basins (south-central Pyrenees, Spain). The stratigraphic interval includes the middle and upper Ypresian, encompassing the early Eocene climatic optimum (EECO). A lower Ypresian assemblage from the Tremp-Ager group (TA) is also discussed. The malacofauna comprises a rich association of intertidal to shallow subtidal species, dominated by Potamidiidae, Batillariidae, Pachychilidae and Cerithiidae, with subordinate Melanopsidae, Thiaridae and Diastomidae. The subtidal fauna is dominated by Turritellidae. The new taxa Peraubium n. gen. (middle-upper Ypresian), Cerithium agervallensis n. sp. (middle Ypresian) (Cerithiidae), Granulolabium pyrenaicum n. sp. (upper Ypresian), Melanopsis cuisiensis n. sp. (upper Ypresian), Pseudobellardia muttii n. sp. (middle-upper Ypresian) (Pachychilidae), Trempotamides n. gen. (middle Ypresian), Cerithideopsis roselli n. sp. (upper Ypresian), Cerithideopsis harzhauseri n. sp. (upper Ypresian), Potamides isabenense n. sp. (upper Ypresian), Tympanotonos morillensis n. sp. (upper Ypresian) (Potamididae) and Melanoides vidali n. comb. (lower Ypresian) (Thiaridae) are introduced. The Cerithioidea fossil record is interpreted according to their local palaeoenvironmental gradients, and by considering their genus-level global stratigraphic distributions in the light of molecular phylogeny, ecology and geographic range of Recent relatives. The study suggests that Potamididae were adapted to intertidal bottoms of mangrove settings since their radiation in Western Tethys. Some early Eocene genera survive in Recent mangrove-fringed coasts. The Batillariidae were adapted to shallow subtidal settings. Their species richness is high, but within genera unrelated to modern forms. Some early Eocene genera attributed to the Pachychilidae lived in marine habitats, contrary to purely freshwater Recent species of that family. Turritellidae were abundant, but not diversified, and occupied a seaward position with respect to all other cerithioidean families.

The geodiversity and hence landscape of the county of Suffolk, England, is dominated by the influence of glacial deposits of the Lowestoft Formation of Anglian (Elsterian) age. This paper is cast as a series of radial excursions from the centre of the county, introducing the elements of pre-Anglian and post-Anglian geodiversity as they relate to this Lowestoftian legacy, featuring particularly the last two million years. Set against two centuries of scientific study of Suffolk’s Earth heritage, it introduces the major elements of the geodiversity of this classic eastern English lowland landscape.

2013.19 These maps (rectilinear projection) are from the PALEOMAP PaleoAtlas for ArcGIS (Scotese, 2013a-f).  This is a digital atlas of plate tectonic, paleogeographic, and paleoclimatic reconstructions designed for use with the GIS software, ArcMap (ESRI).  Table 1 lists the various types of maps that comprise the PALEOMAP PaleoAtlas.  The maps included in this folio are highlighted in bold text (Table 1).
The last map in each folio is a rectilinear graticule that can be overlain on the maps to provide a geographic reference frame.  A rectilinear projection was used because it can be easily georeferenced in ArcMap and transformed into a variety of other map projections.  The rectilinear, or plate caree map projection can also be directly “wrapped” onto a spherical projection, like the oneused by Google Earth. A set of Google Earth paleoglobes has made from the maps in this folio. These Google Earth paleoglobes can be downloaded at: www.globalgeology.com. 
If the map you need is missing, or if there doesn’t seem to be a map folio for the exact time interval of interest, please contact me ([email protected]). Table 2 lists all the time intervals that comprise the PALEOMAP PaleoAtlas for ArcGIS. The PaleoAtlas contains one map for every stage in the Phanerozoic, as well as 6 maps for the late Precambrian.  Eventually, Map Folios, like this one, will be published for every time interval in the PALEOMAP PaleoAtlas.  The following section is a brief description of the maps that makeup the Map Folio.

A new dyrosaurid is described from the Ypresian of the phosphatic deposits of the Oulad Abdoun Basin of Morocco. It is based on numerous cranial and postcranial remains, allowing an almost complete reconstruction. This new Dyrosaurus species, Dyrosaurus maghribensis sp. nov., is currently only known from Morocco. It differs from D. phosphaticus, present in contemporaneous levels of Algeria and Tunisia, by several autapomorpies, including a smooth dorsal margin of the parietal and widely opened choanae. A phylogenetic analysis, using 47 taxa and 234 morphological characters, shows the dyrosaurids as the sister taxon of pholidosaurids, which include Elosuchus, Sarcosuchus, Terminonaris and Pholidosaurus, and the thalattosuchians. Goniopholididae is a non-monophyletic group; however, if dyrosaurids are not included in the analysis, the result differs and the goniopholidids form a distinct clade. If Thalattosuchia is excluded, both Goniopholididae and Pholidosauridae become paraphyletic assemblages. Thus, phylogenetic problems remain with respect to longirostrine clade, and more attention should be paid to resolving their evolutionary relationships amongst the crocodyliforms.

The Eocene was a period of intense climate variability and the response of deep-sea biota is still poorly understood , especially across certain understudied intervals from the middle Eocene. We present new benthic foraminiferal data from a Bartonian marine sequence deposited in the western Tethys Ocean (Torre Cardela section, Spain), and determine the biotic and paleoenvironmental turnover. The assemblages indicate a middle to lower bathyal depth of deposition, and they contain allochthonous taxa (e.g. asterigerinids) that were transported from shallower settings. A Detrended Correspondence Analysis (DCA) performed on the total assemblage differentiates the autochthonous and allochthonous taxa, supporting the idea of different provenience. We suggest that the latter were likely transported downslope by currents. Quantitative analyses of the auto-chthonous assemblages show a strong dominance of calcareous infaunal taxa, mainly bolivinids, which point to a high flux of organic matter to the seafloor. Bolivinoides crenulata, the most common species, is associated with inputs of refractory organic matter and high-energy environments. Five intervals were differentiated based on changes in the relative abundance of taxa. Two intervals (B and D) show the highest percentages of al-lochthonous taxa and B. crenulata. We suggest that enhanced current activity not only transported allochthonous taxa, but also brought in refractory organic matter to the seafloor, which was consumed by opportunistic taxa during these two intervals. We conclude that benthic foraminiferal assemblages at Torre Cardela were strongly controlled by the amount and type of organic matter reaching the seafloor, which were in turn affected by sedimentary and, ultimately, by climatic factors.

The area of western Herzegovina contains a number of Eocene sites with an abundance of macrofossils. Some of the most representative of these sites are located in the municipalities of Čitluk Ljubuski, Široki and Posušje. Among these sites is a significant number of those where have recently discovered endemic, unique or attractive macrofossils. Especially can be noted the fossil fruits of mangrove palm Nypa, terrestrial macroflora, giant oysters, corals and brackish endemic snails from Eocene localities in the municipality of Čitluk. From Eocene locality Grabova draga northeast of Široki Brijeg especially interesting are the discoveries of giant nautilid cephalopods, fossil crabs and many brachiopods. Eocene localities in the municipality of Posušje are probably one of the most fossiliferous Eocene sites in this part of Europe, where is present a real treasure of shallow water fossil communities with molluscs, echinoderms and corals, where you can find one of the largest ever living snail specimens of Campanile giganteum. All these macrofossils and sites of discovering, wearing a very huge scientific paleontological significance, as well as great potential in terms of geotourism.

Une excavation temporaire dans une sablière désaffectée au Quoniam, Haravilliers (Val d'Oise), a rendu à nouveau possible l'examen des couches du Marinésien basal (Bartonien supérieur), notamment le niveau couramment dénommé horizon de Mortefontaine. Bien que précédemment étudié par MORELLET & MORELLET (1922), nos fouilles ont permis d'en préciser la stratigraphie et le contenu paléontologique. Six espèces de gastéropodes, nouvelles pour l'horizon de Mortefontaine, ont été identifiées. Des otolithes de poissons osseux, attribuables à quatre espèces différentes, sont signalés, ce qui est une première pour ce niveau. Abstract: Thanks to a temporary excavation in a disused sand quarry located in Le Quoniam, Haravilliers (Val d'Oise), it has been possible to again study deposits from the basal " Marinesian " , notably a bed commonly named Mortefontaine Member, and their contact with the Auversian. Although previously studied by MORELLET & MORELLET (1922), our digs allowed us to further investigate their stratigraphy and paleontological content. Six gastropod species have been identified, which are new for the Mortefontaine Member. Bony fish otoliths, belonging to four species, are also reported, for the first time from this level

This report re-evaluates the depositional history, biostratigraphic “age,” and regional correlates of Chadron Formation rocks in North Dakota using a variety of data sources. A series of well-developed paleosols are herein recognized for the first time at the top of the Chalky Buttes Member across much of southwestern North Dakota. Those paleosols are contemporaneous with the Weta Paleosol Series of southern South Dakota developed on top of the Chamberlain Pass Formation, and together these paleosols indicate a period of nondeposition and geomorphic stability throughout the Great Plains region following a first phase of late Eocene deposition. Within the Williston Basin, that first phase of deposition begins with rocks dominated by group A heavy minerals (zircon > staurolite > aluminosilicates, tourmaline) that are overlain by rocks dominated by group B heavy minerals (epidote > garnet > zircon). Deposition of these group A and group B rocks would have occurred sometime in the early Chadronian (Ch1-Ch2: 36.9-35.8 Ma).

The second phase of late Eocene deposition in North Dakota consisted of local downcutting of stream channels that were infilled with rocks dominated by group D heavy minerals (hornblende > diopside > epidote). Two faunas are now known from these group D rocks: the late early Chadronian (Ch2: 36.6-35.8 Ma) Medicine Pole Hills local fauna, and the newly reported middle Chadronian (Ch3: 35.8-34.8 Ma) Stover Site local fauna (Adams County, North Dakota). This second phase of deposition occurred after the onset of paleosol development in North Dakota as indicated by the common presence of ferruginous aggregate grains within the opaque heavy minerals from the Stover Site sample that appear to be derived from erosion of paleosols developed on older Chalky Buttes Member rocks that contained group B heavy minerals. Deposition of group D rocks in North Dakota was contemporaneous with portions of those rocks infilling the base of the Red River Paleovalley in southern South Dakota (Ahearn and Crazy Johnson Members).

Deposition of the South Heart Member began gradually during the development of the paleosols within the Williston Basin, indicating those rocks are younger than the group A and group B rocks of the Chalky Buttes Member. Given the lack of biostratigraphic data from the South Heart Member and absence of those rocks within Bowman and Adams Counties where group D rocks of the Chalky Buttes Member are exposed, insufficient evidence is currently available to determine the relative timing of deposition of group D Chalky Buttes Member rocks and those of the South Heart Member. Overall, this study demonstrates that late Eocene deposition was more complicated than previously reported, though these patterns match those found elsewhere within the Great Plains region.

The Eocene Green River Formation and associated fluvial strata host a large variety of widely distributed and laterally extensive synsedimentary to early post-depositional deformation features. Although mostly overlooked in past studies, these structures provide insight into the rheology of the sediments and hydrodynamic conditions at the time of deformation. They also have implications about basin configuration and bottom topography, as well as the structural history of the region.
In the Uinta and Piceance Creek Basins of Utah and Colorado, deformed intervals are present in littoral (sand-dominated) to profundal (oil shale) lacustrine deposits, as well as fluvial facies. Deformation structures exhibit a wide range of morphology, size, and style, ranging from ductile (convolution, folding, load and pinch-and-swell structures) to brittle (microfaults, breccias), to sedimentary injection into fissures and cracks forming dikes, to various mass transport deposits. In most cases, these layers are bound above and below by undisturbed beds of similar facies with horizontal bedding planes, which implies short-lived but recurring events that affected only sediments with a susceptible rheological state. Deformation typically occurred intrastratally, i.e. under shallow burial. The variations in deformation style, size, morphology, and areal extent are related to differences in grain size and type, water content, cementation, organic content, thickness of susceptible material, lateral facies variation, and the nature of the driving force. Some of the sedimentary injection features overprint each other, indicating multiple events affecting a single interval.
We interpret most of these features as seismically induced (‘seismites’) based on: (1) the tectonic setting of the basin; (2) the sedimentary environment and sedimentological characteristics of the host succession; (3) the lateral extent of deformation structures; (4) their recurrence at different stratigraphic levels; and (5) their similarity to those ascribed to seismically induced deformation elsewhere and reproduced experimentally. They developed as a result of increased pore pressure and a complex combination of extensional, compressive, and shear stresses acting in many directions caused by shaking during strong earthquakes. Mass transport deposits indicate in situ disruption and failure of the imperceptibly dipping lake floor. These ‘seismites’ represent the direct sedimentary record of syndepositional tectonic activity in the Uinta Basin.

Fossil material of the Eocene marine sediments of the Crimean Simferopol Formation (Akkaja, Prolom),
Novopavlovsk Formation and Al’Ma Formation (Bachthisarai) as well as the Kazakh Schorym
Formation (Kujulus) has been taxonomically investigated. The following 16 taxa of fossil carcharhinid
and triakid sharks could be specified: Galeorhinus ypressiensis, Iago carlaluisai n. sp., Mustelus cf. vanderhoefti,
Triakis muelleri n. sp., Triakis wardi, Triakis sp.1, Abdounia beaugei, Abdounia lappierei,
Abdounia sp., Galeocerdo latidens, Physodon contortus comb. nov., Physogaleus tertius, Physogaleus
sp., Morphospecies 1, Morphospecies 2, Morphospecies 3. Iago carlaluisai and Triakis muelleri were described
as new species. Physodon (Müller & Henle, 1839) was reintroduced as an independent genus. It
was described as sister group of Physogaleus. The proof of Physodon contortus (Winkler, 1874 B) comb.
nov. for the Middle Eocene, is the oldest fossil record of this species and one of the first safe proofs of the
species in Eurasia. The habitat of the faunal community were warm and tempered offshore waters of the
littoral (Prolom, Ak-kaja, Kujulus) up to the epipelagial (Bachthisarai). The waters were nutritious and
characterized by a high biodiversity. The presented fauna is a typical Tethys fauna and well correlated to
Middle Eocene faunas of North Africa, Europe, India, Central Asia and North America.

In the Sahara Desert of southwestern Morocco, the Aridal Formation of Gueran is known for the world’s richest Bartonian archaic whale assemblage, which includes both protocetids and basilosaurids.
Gueran has also yielded another rich and diverse vertebrate fauna described in detail herein —The chondrichthyan assemblage of twelve species is quite similar to that of the Midawara Formation (Egypt). Actinopterygians include Siluriformes, Percomorpha and rostra of Cylindracanthus Leidy, 1856. Turtles are attributed to at least three indetermined species: two marine cryptodires – a cheloniid and a dermochelyid, and a possible littoral pleurodire, as found in Ad-Dakhla (Morocco) and Fayum (Egypt). The crocodylians comprise at least two longirostrine taxa, including a gavialoid that resembles the late Eocene-early Oligocene Eogavialis africanum Andrews, 1901 from Egypt.
The second form is too fragmentary to be identified more precisely than Crocodyliformes indet. Two snake vertebrae belong to Pterosphenus cf. schweinfurthi Andrews, 1901. Two other incomplete snake vertebrae probably belong to Paleophiidae as well. Seabird remains belong to a gigantic soaring pseudo-toothed bird (Pelagornithidae) and constitute the earliest occurrence of the genus Pelagornis sp. Lartet, 1857.  This material extends the fossil record of Pelagornis back in time by at
least 10 million years. Based on their size and enamel microstructure, mammal dental fragments are attributed to the proboscidean ?Barytherium sp. The Bartonian age of the fauna, initially based on an archaeocete cetacean assemblage, is also supported by chondrichthyans. Affinities of the Gueran faunal assemblage are analyzed in comparison with those from other middle and upper
Eocene deposits of North Africa and elsewhere.

Abstract—The relatively complete late Danian–initial Lutetian succession of biotic events, which are suit
able to serve as biostratigraphic reference levels for interregional correlations are defined in the section of the
Novouzensk reference borehole based on dinocyst and nannoplankton assemblages. The analysis of palyno
logical and nannofossil assemblages allows dynamics of basin development and sealevel fluctuations to be
traced. Three major stages reflecting different sedimentation regimes are established in the borehole section:
(1) Danian with terrigenous–carbonate sedimentation regime corresponding to the Algai and Tsyganovka
formations; (2) Selandian (initial Eocene included) characterized largely by siliceous–terrigenous sediments
of the Syzran, Novouzensk, and, partly, Bostandyk formations; (3) Ypresian–Lutetian with the carbonate–
terrigenous sedimentation regime corresponding to the upper part of the Ypresian Bostandyk and Lutetian
Kopterek formations. The composition of dinoflagellate and nannoplankton assemblages characterizes the
North Caspian basin as an internal largely shallow sea with a changeable temperature regime. The paleoeco
logical analysis of phytocoenoses made it possible to define basin fluctuations comparable with thirdorder
rhythms. Four Danian rhythms definable in the Algai and Tsyganovka formations indicate conditions of an
open warmwater basin. Dynamics of the stepwise shoaling of the basin was characteristic of the Selandian–
early Thanetian ages with subsequent restoration of the marine regime in the late Thanetian. The Syzran For
mation corresponds to two Selandian rhythms, which were formed in shallower settings of the restricted sea
basin. Four Thanetian rhythms are established in the Novouzensk Formation. The early Thanetian basin was
characterized by the shallowest disturbed marine conditions, which were followed by the restored normal
marine regime in the late Thanetian. Six Ypresian rhythms correspond to the Bostandyk Formation (Yp0,
Yp1, Yp5–Yp8) reflecting transition from initial Ypresian coastal (Yp0, Yp1) to normal marine conditions
during the Yp5 rhythm. The late early (Yp2–Yp4)–late (Yp9–Yp10) Ypresian corresponded to the sedi
mentation break. Most abundant and diverse microbiotic assemblages characteristic of the Yp7 rhythm are
correlative with the EECO event. The marly Kopterek Formation corresponding to the early Lutetian rhythm
(Lu1) is characterized by diverse thermophilic biota.

The diversity of Fabaceae in Mexico has a long geological history, and it is particularly rich in sediments from the Oligocene and Miocene. In this work, we describe the first record of two woods resembling ?Cercidoidea and Dialonoidea subfamilies from the Eocene of Chiapas. Both fossil woods have medium to large vessels, abundant paratracheal axial parenchyma, simple perforation plates, short vessel elements, alternate intervessel pits and non-vestured, vessel-ray pits with distinct borders and similar to intervessel pits in size and shape, homocellular (slightly heterocellular) multiseriate rays, prismatic chambered crystals in axial parenchyma cells and in fibers. These characteristics support the inclusion of both woods in Fabaceae. The identification of this new fossil genus (Tzotziloxylon) within Leguminosae, as well as other that have been described earlier from other Eocene localities of Mexico (e.g., Inga, Chamaecrista, and Senna), supports the hypothesis that some genera of this family probably evolved in North America instead of arriving by dispersal from Asia or Africa during the Eocene time.

Even though the Cenozoic has been recognized as a period of important climate change, long-term climatic changes that took place in the continental domain are still questioned. For an area, southern Germany, for which other long-term palaeoclimatic records exist, analysis of oxygen isotope composition of small mammal teeth has been carried out for localities ranging in age from the late Eocene (c.36 Ma) to the middle Miocene (c.10 Ma). Comparison of this long-term continental δ18O record with the marine record reveals comparable trends. The major Cenozoic climatic events are thus recognized in the continental oxygen isotope record.Through comparison with other quantitative palaeoclimatic reconstructions available for the studied area, temperatures in southern Germany are broadly estimated to have fluctuated between 12 °C and 25 °C from late Eocene to early late Miocene. According to the different available chronological frameworks, either a ∼ 2 °C (considering the classical biostratigraphy) or a ∼ 6 °C (considering a revised biostratigraphy) decrease in mean air temperature is estimated for the Eocene/Oligocene boundary.

Baltic amber constitutes the largest known deposit of fossil plant resin and the richest repository of fossil insects of any age. Despite a remarkable legacy of archaeological, geochemical and palaeobiological investigation, the botanical origin of this exceptional resource remains controversial. Here, we use taxonomically explicit applications of solid-state Fourier-transform infrared (FTIR) microspectroscopy, coupled with multivariate clustering and palaeobotanical observations, to propose that conifers of the family Sciadopityaceae, closely allied to the sole extant representative, Sciadopitys verticillata , were involved in the genesis of Baltic amber. The fidelity of FTIR-based chemotaxonomic inferences is upheld by modern–fossil comparisons of resins from additional conifer families and genera (Cupressaceae: Metasequoia ; Pinaceae: Pinus and Pseudolarix ). Our conclusions challenge hypotheses advocating members of either of the families Araucariaceae or Pinaceae as the primary...

Magyarcarcinidae is proposed as a new family to accommodate the genus Magyarcarcinus. A new species, Magyarcarcinus yebraensis is erected after specimens from Bartonian levels of the Margas de Arguís Formation at Yebra de Basa (Aragón, N Spain). A detailed comparison with all the Goneplacoidea families and related taxa is presented. Relationship between both Tethyan and British Middle Eocene decapod faunas are herein confirmed, as well as their migration paths.

Magyarcarcinidae new family (Crustacea: Decapoda: Goneplacoidea), and description of Magyarcarcinus yebraensis new species, from the Bartonian (Middle Eocene) of the Jaca basin, south-central Pyrenees (Aragón, N Spain). Available from: https://www.researchgate.net/publication/313854322_Magyarcarcinidae_new_family_Crustacea_Decapoda_Goneplacoidea_and_description_of_Magyarcarcinus_yebraensis_new_species_from_the_Bartonian_Middle_Eocene_of_the_Jaca_basin_south-central_Pyrenees_Aragon_N [accessed May 3, 2017].

Newly described specimens of North American Eocene turtles provide valuable information on their morphology and, more specifically, variation, both intraspecific and ontogenetic. We describe several complete and nearly complete testudinoid (Testudinoidea) specimens, including juvenile specimens of Hadrianus corsoni, H. majusculus, Echmatemys haydeni and E. naomi. These specimens help us determine that the oldest and most basal tortoises are from the western United States, suggesting Testudinidae evolved in North America from one of the geoemydid-like forms in the genus Echmatemys, which have their lowest stratigraphic occurrence in the earliest Wasatchian North American land-mammal “age” (early Eocene, Ypresian, ~53 Ma).

RESUMEN-Se confirma la presencia del género Rhabdobrissus Cotteau, 1889 en el Eoceno y se revisan las especies descritas en este período. Se recuerda y se comenta la relación de este género con Plagiobrissus. Los materiales estudiados constituyen la primera cita de Rhabdobrissus en España y se concluye que los ejemplares estudiados pertenecen a la especie Rhabdobrissus fabianii (Lambert, 1910).

ABSTRACT-The occurrence of the genus Rhabdobrissus Cotteau, 1889, is confirmed in the Eocene and the species found in this period are reviewed. The relationship of this genus with Plagiobrissus is remembered and commented on. The specimens studied are the first record of the genus Rhabdobrissus (Echinoidea) in Spain and they are ascribed to the Rhabdobrissus fabianii (Lambert, 1910) species.

A B S T R A C T As an important geological archive, paleosols have been widely used in reconstruction of paleoenvironmental and paleoclimatic conditions. In this study, we undertook detailed analyses of the clay mineralogy and carbon and oxygen isotopic compositions of pedogenic carbonates in a series of 13 paleosol horizons within a fluvial section of the Eocene (~52–44 Ma) Lulehe Formation in the Qaidam Basin. Pedogenic smectite and illite/ smectite (I/S) mixed-layer minerals are the predominant clay minerals in the paleosols, suggesting that the early Eocene paleoclimate of the Qaidam Basin was strongly seasonal with warm-wet summers. The high levels of pedogenic smectite production and high atmospheric pCO 2 reconstructed from soil carbonate nodule δ 13 C (mean −7.1 ± 0.8‰) are consistent with elevated temperatures during the Early Eocene Climatic Optimum (EECO). Coeval paleosol carbonate nodules yield estimated paleo-surface water compositions (δ 18 O psw) of −7.9‰ to −5.0‰ (VSMOW), which are significantly higher than the δ 18 O value of modern summer precipitation in the Qaidam Basin. The estimated temperature difference (~5.0 °C cooling) implies uplift of the study area by nearly 1000 m to its current average elevation of ~3000 m above sea level. This paleoelevation estimate agrees with modern meteoric water isotopes of Global Network of Isotopes in Precipitation (GNIP) sites in Asia in the same elevation range.