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This study concerns a long marine section (DSDP Site 380: Late Miocene to Present) and onshore exposed sections from the Late Miocene and/or Early Pliocene. The main target of this study is to reconstruct vegetation and climate in the North Anatolia and North Aegean region for the last 7 Ma. Two vegetation types were alternately dominant: thermophilous forests and open vegetations including Artemisia steppes. During the Late Miocene, most of the tropical and subtropical plants declined because of the climatic deterioration. However, some of them survived during the Late Pliocene, such as those which constituted coastal swamp forests (Glyptostrobus, Engelhardia, Sapotaceae, Nyssa) or composed deciduous mixed forests with mesothermic trees. Simultaneously, herbaceous assemblages became a prevalent vegetation component despite steppe elements (Artemisia, Ephedra, Hippophae rhamnoides) did not significantly develop. At 2.6 Ma, as a response to the onset of Arctic glaciations, subtropical elements rarefied despite some taxa persisted (Glyptostrobus, Engelhardia, Sapotaceae, Nyssa). In parallel, deciduous mixed forest assemblages composed of mesothermic trees (deciduous Quercus, Betula, Alnus, Liquidambar, Fagus, Carpinus, Tilia, Acer, Ulmus, Zelkova, Carya, Pterocarya) almost disappeared too while steppe environments strongly enlarged. Then, Artemisia steppic phases developed during longer temporal intervals than mesophilous tree phases all along the glacial-interglacial cycles (first with a period of 41 kyrs, then 100 kyrs). Since 1.8 Ma, herbaceous ecosystems including Artemisia steppes still continuously enlarged up today. Such an expansion of Artemisia steppes in the Ponto-Euxinian region was observed at the earliest Pliocene but their earliest settlement in Anatolia seems to have occurred in the Early Miocene. The development of the Artemisa steppes in Anatolia might result from the uplift of the Tibetan Plateau. Relictuous plants such as Carpinus orientalis, Pterocarya, Liquidambar orientalis, Zelkova persisted up today. This story can be explained by some influence of the Asian monsoon which reinforced as a result from the uplifted Tibetan Plateau.

The study of fossil istiophorids is limited by its fragmentary fossil record; the absence of osteological specimens for comparisons; the cryptic bibliography of several early works and the absence of more accurate comparative methods. Appling a data imputation model we took advantages of extant data for rostral and articular variables for istiophorid billfishes. We used this result to apply PCA analysis and we compared fossil and modern istiophorids together. With this analysis we present here two new istiophorid species: Makaira? sp. nov. 1 and Makaira sp. nov. 2. Makaira? sp. nov. 1 is the most complete fossil istiophorid ever discovered and represent that share characters in various genera. We hypothesize that characters in bones involved in alimentation process have phylogenetic importance as: rostrum shape, denticles, lower jaw, vomer, basioccipital and skull shape as well as orbital size. Our taxonomic reviews of fossil istiophorid reorganize its taxonomy and solve many conflicts about the classification of fossil species. The istiophorids are abundant macrovertebrate in the Chagres sediments and its presence suggests a water column with a minimum of 200m depths in an environment of short platform with oceanic influence. Given the high productivity inferred in this environment we suggest that...

The Late Neogene sedimentary sequence of the Murray Basin provides an excellent opportunity to examine paleoenvironmental change across southeastern Australia. A detailed stratigraphic analysis of sediments deposited within the basin in the last 10 Ma was undertaken to assess the influence of tectonic and eustatic processes on deposition. / Stratigraphic observations and radiogenic isotope analysis reveals the onset of deposition by 7.2 Ma with a transgressive episode that deposited the marine marls of the Bookpurnong Beds. Deposition was restricted to the central and eastern parts of the basin due to the Hamley Fault. In the west, subsurface elevation contours indicate the presence of incised paleodrainage channels above Miocene limestones, which facilitated the formation of a large estuary system at 5.3 Ma. The sediments of the Norwest Bend Formation were deposited within this western region, while further east, the Loxton-Parilla Sands strandplain deposited over 214 coastal ridges. The basal parts of this unit occur as lateral equivalents to the sediments of the Lower Norwest Bend Formation (in the west). Topographic and magnetic data reveal that tectonism was active during this period and resulted in the erosion and truncation of strandlines. / Tectonic evidence and an estimated minimum 28,037 year cyclicity between strandline sets, suggests that the Loxton-Parilla Sands strandlines do not represent an unbroken record of glacioeustatic change. The subaerial exposure of these sediments at approximately 3.0 Ma caused the formation of a calcareous karst above the Norwest Bend Formation and a ferruginous and/or silicious cap (the Karoonda Surface) above the Loxton-Parilla Sands. The stratigraphic position of these surfaces are indicative of a regional widespread unconformity. / The Douglas-Blackburn paleodrainage system in western Victoria was dammed during the Mid-Late Pliocene by uplift associated with the Padthaway High, which caused the formation of a 400,000 km2 lacustrine system, known as Lake Bungunnia. Topographic analysis indicates that Lake Bungunnia comprised at least four distinct sub-basins with water depths of up to 30 metres, with lake shorelines indicating that active tectonism occurred during this period. The resulting lack of sediment input to the coast caused the formation of the Kanawinka Escarpment, a large erosional scarp along the southern margin of the Padthaway High. / The geomorphology of the modern Murray Basin can be directly attributed to the demise of the Lake Bungunnia system. Movement along the Morgan Fault in the west at approximately 700 Ka, resulted in the draining and progressive drying of Lake Bungunnia as a breach was created along the Padthaway High. The Murray River gorge as observed today was incised following this episode. The modern Murray River (and playa lakes such as Lake Tyrell) occupy the lowest elevations along the former sub-basins of Lake Bungunnia. / The Late Neogene sedimentary sequence across the Murray Basin illustrates a complex interaction of eustatic and tectonic processes on deposition. Sedimentation within strandline, estuarine and lacustrine systems, particularly in the western Murray Basin, display evidence of significant tectonic control. This highlights the important role that neotectonic processes have played in shaping southeastern Australia.

My PhD and post-doctorate researches have focused on paleoclimatic, paleogeographical and paleoenvironmental reconstruction of the Mediterranean Basin and its adjacent seas (i.e. the residual former Paratethys) since 11 Ma. During this time-interval the Mediterranean marine and continental environments were affected by significant paleogeographic changes, forced by global climate and sea-level variability, plate tectonics and regional uplift of Alps s.l. and Carpathians. Two main important events characterize this period: the isolation and evolution of Paratethys and the almost complete desiccation of the Mediterranean Sea, an event known as the Messinian Salinity Crisis. I selected this region because it is very rich in long and continuous sediment archives, which document: (1) climate evolution of the Northern Hemisphere during the Late Cenozoic with respect to vegetation changes, and (2) progressive evolution of initially marine environments towards brackish and freshwater ones. The brackish to fresh environments had a profound effect on the marine organisms (especially dinoflagellates) that responded to the stress by developing a large variety of cyst morphologies, often described as new genera and/or species. Methods. The comparative analysis of pollen grains and dinoflagellate cysts from the same samples is rarely performed for such a long time-interval because it needs a deep knowledge in taxonomy and ecology of the both complementary proxies. I reached this parallel expertise, having the benefit of training in (1) botanical identification of pollen grains from the tropical to boreal zones and their ecological significance by Dr. J.-P. Suc, (2) taxonomy and ecology of dinoflagellate cysts by Pr. M. J. Head. To achieve an understanding of the primary factor inducing morphological variations of dinoflagellate cysts, I developed a biological approach (culturing and growing of present-day living dinoflagellates and inducing stress on microcultures experimentations) under supervision of Pr. J. Lewis (Westminster University, London, UK) and Drs. D. Anderson and D. Kulis (WHOI, USA) during my postdoc appointments. The simultaneous work on living and fossil (using biometry and associated statistical analyses) dinoflagellate cysts has allowed me to initiate the development of a transfer function, widely valid and able for the modelling of the physical parameters of sea-surface waters (salinity, temperature, nutrient contents). Such analyses were performed at high- to very high-chronological resolution, as resulting from the following approach: (1) independently established age-model, based on classical biostratigraphy or radiocarbon ages (for recent sediments), completed by magnetostratigraphy for deposits prior to Mid–Quaternary; (2) comprehensive counting of pollen grains (150 per sample, Pinus or any overabundant taxon excepted) and dinoflagellate cysts (200-300 per sample); (3) interpreting the resulting data with respect to ecological requirements. High- to very high-resolution analyses provides results directly comparable with classical oxygen isotope curves. These signals can therefore also be tuned to the frequency of eccentricity, obliquity and precession cycles. Although palynological proxies can be considered as standard, my integrated approach hoists them at the level of the most competitive methods. Another aspect consists in its present-day background, based on many surface samples from the Mediterranean, Marmara and Black seas, taken during several cruises and sampling parties at IFREMER-Brest and WHOI. To develop parallel analyses of pollen grains and dinoflagellate cysts offers additional considerable interests, such as (1) continuous records of climatic changes and sea-level variations independently from sediment types, and (2) quantifications (using transfer functions) of climate for both continental and marine (to brackish) realms as well as of physical oceanic parameters (SST, SSS, nutrient content etc.).<br /><br />Results and research in progress<br />Using pollen grains analysis, I developed investigations on vegetation dynamics and paleoclimate reconstructions for the whole Mediterranean region and Western Europe extended to the Late Cenozoic (Jiménez-Moreno et al., 2007; Fauquette et al., 2006). Thanks to the high-chronologic resolution: <br />a. I established the response of regional vegetation to eccentricity forcing in SW Romania (Dacic Basin) and Black Sea (DSDP Site380) whatever the sediment types (Popescu, 2001, 2006; Popescu et al., 2006a);<br />b. I was the first to demonstrate the precession forcing on regional vegetation (Popescu et al., 2006b) through the Lupoaia pollen record (SW Romania);<br />c. in the frame of two PhD theses that I co-supervise, pollen grain and dinoflagellate cyst records from DSDP Site 380 (7 - 4 Ma) were completed from 4 Ma to Present in order to evidence the impact of glacial-interglacial cycles over the regional vegetation and to reconstruct the climate variability for the last 7 Ma;<br />d. I was the first to demonstrate the solar cycles forcing (Hale and Gleissberg cycles) on the regional vegetation (through the “Thermophilous trees / Artemisia” ratio) since the Last Glacial Maximum were evidenced in cored sediments from the Black and Marmara seas (unpublished data), that is a unique outcome. <br />Using the biometric approach on the dinoflagellate cysts in association with statistical analyses, I demonstrated that fluctuations in salinity are partially responsible for modifying size, shape and ornamentation of the cysts, providing the first reliable paleoecological and paloebiogeographic reconstructions of the brackish Paratethyan basins (Popescu et al., palynology , in press). <br />Simultaneously, I performed experimental cultures on a living-dinoflagellate species (Scrippsiella trifida): suggested relationships between cyst morphological variations and stress under controlled salinity are confirmed by the preliminary results, while reproduction rate seems also modified (unpublished data). <br />The multi-proxy (palynology, sedimentology and geochemistry) study on the Aral Sea, done by the first PhD student that I co-supervised, allowed not only the reconstruction of the regional paleoclimate and paleoenvironments, but also permitted to understand the atmosphere dynamics of the last 2 ka over the high latitudes (Sorrel et al., 2006, 2007). <br />Hence, my palynological and biological expertise offers an exclusive tool for establishing a continuous high resolution chronology, paleoclimatic, paleobiogeographic and paleoenvironmental reconstructions. This is particularly important for the basins impacted by important environmental changes, such as the Mediterranean and Black seas, the sediments of the latter being precisely dated for the first time by this approach.<br /><br />I do no want to close this Introduction Section without addressing my largest acknowledgements to those who supported my researches and expressed their interest in my project, providing personal grants and/or financial assistance for achieving my researches, and especially the PhD and master – graduation students that I appreciated so much to co-supervise.

Le flux de sédiments en provenance des Alpes montre une importante augmentation à la limite Mio-Pliocène (⊥5 Ma). Cette observation, liée à l'exhumation du bassin molassique suisse depuis 5-4 Ma, a conduit à suggérer que les Alpes ont connu une exhumation et un uplift isostatique accélérés à l'échelle de l'orogène depuis cette période. Les objectifs principaux de cette thèse sont de déterminer s'il existe une hausse de l'exhumation alpine après 5 Ma, de préciser son extension spatiale et temporelle, et de passer en revue les différents facteurs potentiels (tectoniques ou climatiques) contrôlant cette dénudation. J'ai développé durant la thèse une nouvelle technique utilisant les contours isoâge associés aux relations âge-élévation pour, à partir de la mise à jour d'une base de données d'âges par traces de fission dans les Alpes Européennes occidentales, reconstruire des surfaces de refroidissement isoâge et estimer les taux d'exhumation de l'orogène entre 13,5 et 2,5 Ma. Les taux et les périodes d'exhumation obtenus pour huit zones des Alpes Occidentales présentent de fortes similarités avec la dénudation moyenne de l'orogène estimée à partir du volume de sédiments péri-alpins. Les taux d'exhumation ont plus que doublé depuis la fin du Miocène, et peuvent avoir été modulés localement par les caractéristiques des différentes unités tectoniques. J'ai ensuite recherché des corrélations entre les valeurs de taux d'exhumation à long terme, dérivées des données d'âge par traces de fission, et les paramètres de contrôle potentiels. Dans les Alpes Occidentales, les taux d'exhumation à long terme sont fortement corrélés avec les taux d'uplift rocheux présents, suggérant que les valeurs d'uplift actuelles ont peu changé récemment. J'ai aussi observé que la distribution de l'énergie sismique libérée n'est pas corrélée avec l'uplift rocheux ou l'exhumation, ce qui suggère que l'exhumation est contrôlée par rebond isostatique plutôt que par un uplift tectonique actif. L'absence de corrélation entre les taux d'exhumation et la distribution des précipitations actuelles suggère qu'elles ne sont pas représentatives d'une tendance à long terme, ou bien que des facteurs autres que le taux de précipitations contrôlent l'intensité de l'exhumation. Dans le but d'étudier davantage en détail l'histoire de l'exhumation, j'ai réalisé un échantillonnage le long de deux profils altitudinaux dans le centre du massif de l'Aar (Suisse) et à l'ouest des Alpes Lepontines (Italie). Les âges AFT et AHe obtenus se caractérisent par des pentes très élevées de la relation âge-élévation aux alentours de 8 et 4 Ma. J'ai utilisé le modèle Pecube pour prédire des âges AFT et AHe selon plusieurs dizaines de scénarios d'exhumation, et j'ai comparé les âges mesurés et prédits. Les résultats des modèles numériques ne permettent pas de rejetter l'hypothèse de deux phases de forte exhumation à 9-7 et 5-3 Ma dans le massif de l'Aar. Cependant, ce signal n'est pas détecté dans les Alpes Lepontines, et sous-réserve de l'apport d'une modélisation flexurale additionnelle, la quantité d'exhumation dans le massif de l'Aar depuis 5 Ma ne permet pas d'expliquer l'exhumation du bassin molassique suisse par rebond flexural isostatique. Au contraire, ces résultats sont de nature à conforter l'existence d'un mécanisme d'uplift rocheux additionnel tel que le détachement de manteau lithosphérique épaissi.

Palaeosurfaces and palaeovalleys are landforms under destruction in the present climate and/or tectonic regime, and thus mainly reflect processes not active today. Uplifted palaeosurfaces exist along the formerly glaciated passive continental margins around the North Atlantic. Large-scale landform development has recently become a matter of interest also for geologists and geophysicists as the result of an increasing awareness that a thorough knowledge of uplift, erosion, deposition and development of landforms along continental margins can only be accomplished by combined studies using independent data from different scientific disciplines. The present study focuses on one of these above data sets; the landform record. Two uplifted areas, southern Norway and central West Greenland, were selected for landform analysis of high resolution digital elevation models, aerial photographs, relation between landforms in basement and cover rocks, offshore seismic lines and X-ray diffraction of clay minerals in saprolites. In southern Norway, analysis of slope angles within the range of pediment slopes was combined with analysis of main valley incision. This resulted in the identification of three main planation surfaces in a stepped sequence formed along the main valleys as a consequence of tectonic uplift events, maybe in the Palaeogene, (in total &gt;1000 m). Two phases of late uplift (~900 m), probably in the Neogene, triggered incision of deep fluvial valleys, later reshaped by glacial erosion (up to 300 m). In central West Greenland palaeosurfaces were analysed in relation to cover rock of different age. An exhumed etch surface, characterized by a typical hilly relief, occurs on Disko and south of Disko Bugt, and are by the presence of cover rocks shown to be sub-Palaeocene in origin. To the north, a post-Eocene erosion surface on Nuussuaq, cuts across basement and basalt and was probably formed close to sea level. Uplift in two phases elevated this surface up to 2000 m above present sea level and broke it in differently tilted tectonic blocks. South of Disko Bugt, a planation surface, of probably the same age as the one on Nuussuaq, cuts the tilted etch surface, and also cuts across different bedrock types. The planation surface rises towards the south and splits in two surfaces, separated in altitude up to 300 m, within two highly elevated areas. The separation into two surfaces indicate two uplift events: A first minor event of a few hundred metres in the uplift centres resulted in incision of the lower planation surface. This event was later followed by a major uplift event amounting to &gt;1000 m. Correlation with the offshore sedimentary record suggests that both uplift events occurred in the Neogene. The erosion pattern calculated from one reconstructed palaeosurface to present topography shows large spatial variations. This is interpreted as an effect of differential bedrock resistance and local variations of glacial erosion (400–1300 m in low areas). The results presented in this thesis demonstrate the usefulness of palaeosurfaces and palaeovalleys as tools for deciphering magnitude of uplift events, establishing relative event chronologies and for calculation of erosion. Moreover integrated studies of palaeolandforms, offshore geology and thermal chronologies, are shown to be invaluable when used to solve the spatial and temporal patterns of uplift, erosion and deposition.

High rates of Neogene sediment influx to the offshore Canterbury Basin resulted in preservation of a high-resolution record of seismically resolvable sequences (~0.1-0.54 my periods). Subsequent sequence development was strongly influenced by submarine currents. This study focuses on correlating seismically interpreted sequence boundaries and sediment drifts architectures beneath the modern shelf and slope with sediment facies observed in cores from shelf Site U1351 and slope Site U1352 drilled by Integrated Ocean Drilling Program (IODP) Expedition 317. A traveltime-depth conversion was created using sonic and density logs and is compared with two previous traveltime-depth conversions for the sites. Eleven large elongate drifts were interpreted prior to drilling. Two new small-scale plastered slope drifts in the vicinity of the IODP sites, together with sediment waves drilled at Site U1352, have been interpreted as part of this study. Lithologic discontinuity surfaces and transitions together with associated sediment packages form the basis of identifying sequences and sequence boundaries in the cores. Contacts and facies were characterized using shipboard core descriptions, emphasizing grain-size contrasts and the natures of the lower and upper contacts of sediment packages. Lithologic surfaces in cores from sites U1351- (surfaces S1-S8) and U1352- (surfaces S1-S6) correlate with early Pleistocene to recent seismic sequence boundaries U12-U19 and U14-U19, respectively. The limited depths achieved by downhole logging, in particular sonic and density logs, together with poor recovery in the deeper section did not allow correlation of older lithologic surfaces. Slope Site U1352 experienced a complex interplay of along-strike and downslope depositional processes and cores provide information about the principal facies forming sediment waves. The general facies are fine-grained mud rich sediment interbedded decimeter-centimeter thick sand and sandy mud. Core evidence for current activity is reinforced at larger scale by seismic interpretations of sediment waves and drifts. / text

Στην εργασία αυτή αρχικά πραγματοποιείται μια σύντομη περιγραφή της γεωλογίας του νομού Αχαΐας με παράθεση στοιχείων της σεισμικότητάς της ευρύτερης περιοχής καθώς και παράθεση υδρομετεωρολογικών στοιχείων. Η σπουδαιότητα των στοιχείων αυτών έγκειται στην κατανόηση του ευρύτερου γεωλογικού περιβάλλοντος στο οποίο ανήκουν και οι σχηματισμοί των οποίων οι ιδιότητες διερευνήθηκαν. Ακολουθεί η περιγραφή των εργαστηριακών δοκιμών που εκτελέστηκαν, σύμφωνα με τις προδιαγραφές της ισχύουσας νομοθεσίας αλλά και της διεθνούς πρακτικής. Στη συνέχεια σχολιάζονται θέματα σχετικά με την δειγματοληψία και την περιγραφή των γεωλογικών σχηματισμών που απασχολούν την εργασία αυτή. Παρουσιάζονται αναλυτικά ο τρόπος και οι θέσεις λήψεως δειγμάτων, ενώ παρέχονται και στοιχεία από τη γεωλογία της εκάστοτε περιοχής σε μια προσπάθεια να συγκεντρωθούν κατά το δυνατόν περισσότερα δεδομένα που συσχετίζονται με τους εδαφικούς σχηματισμούς που μελετήθηκαν. Δίνονται, τέλος, τα αποτελέσματα των εργαστηριακών δοκιμών και παρουσιάζονται τα συμπεράσματα που προέκυψαν, ενώ παρατίθενται και τα πλήρη στοιχεία που αφορούν στην εκτέλεσή τους. Στα πλαίσια του στόχου της πλήρους ανάλυσης και της απόδοσης μιας ολοκληρωμένης εικόνας των σχηματισμών, εκτελέστηκαν, πλέον των εργαστηριακών δοκιμών προσδιορισμού των παραμέτρων διατμητικής αντοχής και δοκιμές προσδιορισμού των αντίστοιχων παραμέτρων που σχετίζονται με τις φυσικές τους ιδιότητες. Με τα στοιχεία που προέκυψαν έγινε μια απόπειρα συσχετισμού των μεγεθών μεταξύ τους, ώστε να διαφανούν πιθανές εξαρτήσεις και να εξηγηθούν διαφοροποιήσεις στα αποτελέσματα των δοκιμών. / In this essay there is initially presented a short description of the geology of prefecture Achaia with apposition of data of it’s wider region seismicity as well as apposition of hydrometeorological data. The importance of presenting this data lies in the comprehension of the wider geological environment in which the formations of this work’s interest belong. Then there follows the description of laboratorial tests that were executed, according to the specifications as presented in effect legislation but also set by international practice. There are also presented subjects with regard to the sampling methods and the description of geological formations that occupy this work’s area of interest. There are analytically presented the way and the sites of reception of samples, while there is also analyzed information regarding to the geology of each site in order to collect as much data connected to the soils that were studied as possible. There are finally presented the results of laboratorial tests (and also the conclusions that resulted). In the objective of complete analysis and the understanding of the marl-type soils that were investigated, along with the elements that resulted, there was an attempt of correlation between shear strength parameters and soil properties, so that should emerge likely dependences and would be explained differentiations in the results of laboratory testing.

This Ph.D. dissertation integrates stable isotope and trace element geochemistry in modern and fossil gastropod shells to study low-latitude marine paleoenvironments. First, stable isotopes (delta18O and delta13C) and Sr/Ca ratios are used to examine low-latitude temperature and salinity variations recorded in Plio-Pleistocene (3.5-1.6 Ma) fossils from western Florida during periods of high-latitude warming and "global" cooling. The middle Pliocene Pinecrest Beds (Units 7 and 4) and the overlaying Plio-Pleistocene Caloosahatchee Formation generate significantly different delta18O-derived paleotemperatures but identical Sr/Ca ratios. High delta18O values, together with low delta13C values and brackish fauna, indicate that Unit 4 was deposited in a lagoonal environment similar to modern Florida Bay. In contrast, relatively low delta18O and high delta13C values in Unit 7 and Caloosahatchee Formation represent deposition in an open-marine environment. The observed Unit 7 and Caloosahatchee paleotemperatures are inconsistent with middle Pliocene warming event, but consistent with the Plio-Pleistocene cooling trend. To quantify modern upwelling and freshening signals and contrast these signals between the tropical eastern Pacific (TEP) and southwestern Caribbean (SWC), methodologies are developed for reconstructing seasonal upwelling and freshening patterns from modern tropical gastropod shells from Panama using: 1) paired oxygen and carbon isotopic profiles and delta18O-delta13C (delta-delta) correlations, and 2) deviation from baseline delta18O values that represent conditions free of seasonal upwelling or freshening influences. Shell delta18O values normalized to the baseline faithfully record modern conditions of little or no upwelling in SWC and Gulf of Chiriqui, and strong upwelling in the Gulf of Panama, as well as strong freshwater input in most areas. The baseline and delta-delta methods are applied to identify and quantify changes in upwelling and freshening in the Neogene TEP and SWC seawaters associated with the final closure of Central American Isthmus. The records reveal significant upwelling in late Miocene SWC and mid Pliocene TEP waters, strong freshening in SWC waters from 5.7-2.2 Ma, and minimal seasonal upwelling and/or freshening variations in Plio-Pleistocene SWC waters. The reconstructed paleotemperatures agree with the global cooling trend through the late Miocene, but lack evidence for middle Pliocene warming or late Neogene global cooling.