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Cuttings and logs from four boreholes in the Mediterranean Sea, offshore the northwestern side of the Nile Delta, Egypt (30°00'–30°24' N, 31°18'–31°30' E), were examined lithostratigraphically, biostratigraphically and paleoenvironmentally. Five planktonic foraminiferal zones were determined assigning the studied boreholes to be late Miocene-Early Pliocene in age. These zones are Globorotalia mediteraneaneana Zone Sphaeroidinellopsis seminulina Zone, Globorotalia margaritae margaritae Zone, Globorotalia puncticulata Zone and Globorotalia inflate. Studying benthonic foraminifera indicated a general shallowing upward trend in all boreholes and tracking the distribution of the foraminiferal assemblages by counting the total number of foraminifera and planktic/benthic ratios provide a history of the progression of deltaic facies with secondary cycles of sea-level change. [ABSTRACT FROM AUTHOR]

The Mediterranean Basin has been subjected to important geological and paleogeographic events that have shaped the evolution of the faunal assemblages that inhabit it. Two main events can be highlighted, the closure of its eastern margin by the Gomphotherium Land Bridge, and the temporal closure of the connection to the Atlantic Basin during the Messinian Salinity Crisis. These two events shaped the diversity of the chondrichthyan assemblages of the Mio–Pliocene Mediterranean, and their consequences can be observed even in the modern faunal composition. To better understand the taxonomic and ecological composition of the Mediterranean chondrichthyan faunas between the aforementioned events, and how they affected their evolutionary dynamics, we have performed a complete systematic and paleoenvironmental study of the chondrichthyan assemblage recovered from various Late Miocene localities at the municipality of Alcoy Basin (Alicante, eastern Spain). Our analysis allowed us to recognize up to 20 taxa of sharks and rays recovered from Miocene deposits. In addition, we reconstruct the paleobathymetry of the El Muro fossil site, based on the estimation of the Oceanization Index for foraminifera, as well as by the elasmobranch fossil assemblage via weighted bootstrap analysis. We expect that this first description and study of the Miocene chondrichthyan taxa from this area of eastern Spain could help us create a comparative framework to compare these communities with other areas, as well as show the changes in the elasmobranch species that have inhabited the Mediterranean Basin during and after the Messinian Salinity Crisis. [ABSTRACT FROM AUTHOR]

Parchment is one of the most abundant resources in archives across the world and is a unique time-sensitive material through which centuries of livestock economies, trade and craft can be explored. We examine the impact of structural and chemical modifications during production to δ13C and δ15N values in the skin, particularly the removal of cutaneous keratins and lipids and the conversion of amide functional groups into carboxyl groups via alkaline hydrolysis. Through the manufacture of 51 parchment skins (sheep, goat, calf and pig) using both historic and modern manufacturing techniques, we found production resulted in a small enrichment in 13C (average +0.12‰) and 15N (+0.26‰). Our results pave the way for the isotopic analysis of parchment in paleodietary and paleoenvironmental studies for the historic period and establish the acceptable C:N ratios in deamidated collagenous tissues. [ABSTRACT FROM AUTHOR]

There are four sets of source rocks from Carboniferous (C) to Permian in Mahu Sag, and the paleoenvironment is the decisive factor for the differences of source rocks. In order to study the controlling effect of paleoenvironmental evolution on the change of source rock properties, the major, trace elements and the total organic carbon (TOC) of 47 core samples from four sets of source rocks were tested. The results indicate that the paleoenvironmental evolution of these four sets of source rocks from C to Permian in Mahu Sag can be divided into five stages. At the end of C and the early stage of deposition of Wuerhe formation (P2w), the paleo climate became warm and humid, and the salinity of water body became small. Meanwhile, the oxidizability of water body gradually became stronger. At the deposition stage of Jiamuhe Formation (P1j), Fengcheng Formation (P1f) and the late stage of deposition of P2w, the paleo climate gradually became hot and dry, and the salinity of water body gradually increased. Meanwhile, the reducibility of water body became stronger. The paleoenvironmental factors controlling the abundance of organic matter in source rocks are different in different stages. [ABSTRACT FROM AUTHOR]

Palaeokarsts are rarely preserved and recognized from Precambrian strata. However, a Mesoproterozoic palaeokarst was recently discovered on the top of the Tuanshanzi Formation in Xingcheng, Liaoning Province, China. This palaeokarst recorded karstification fissures, three types of breccias and unique vadose filling. Four factors: no bedding fillings, vadose cements, restricted palaeokarst development, and the overlying beds without involved any karstification, supported this palaeokarst occurred before the deposition of the Dahongyu Formation. Relative sea-level changes and tectonic movement provided the essential external cause for this palaeokarst, which revealed the hiatus between the Dahongyu Formation and the Tuanshanzi Formation in the Yan-Liao Aulacogen of the North China Craton. This finding was significant and valuable for discussing the 'Xingcheng Movement' and unconformity contact relationships between the two formations observed around the basin. As the palaeokarst did not extend to the interior of the basin and the unconformity occurred mainly in the margins of basin, the significance of them is always underestimated. Nevertheless, this palaeokarst and other sedimentary features could represent an apparent transition of Yan-Liao Aulacogen basin evolved from rift to depression under the background of Supercontinent Columbia breakup. [ABSTRACT FROM AUTHOR]

Middle Eocene Fulra Limestone and Oligocene Maniyara Fort Formation represent platform carbonate deposits of Kutch at the north-western margin of India. These carbonates contain larger benthic foraminifera, including Alveolina, Assilina, Discocyclina, Lepidocyclina, Miogypsina, Nummulites and Spiroclypeus. This study presents paleodepositional and paleobathymetric interpretations for both formations using benthic foraminifera in combination with lithological association, sedimentary structures and early diagenetic features. The six carbonate facies comprising the Fulra Limestone indicate a depositional spectrum ranging from bar-lagoon to mid-ramp depositional conditions. It records several shallowing upward cycles, leading to emergence and formation of paleokarst. The four carbonate facies of the Maniyara Fort Formation represents deposition within the inner ramp setting in bar-lagoon and patch-reef environment, while intervening fine siliciclastics correspond to episodes of relative sea level fall. Nummulitic accumulations form low-relief bars within the fair weather wave base in both the formations. The depositional setting of the Paleogene carbonate in Kutch broadly resembles Eocene platformal deposits in the circum-Tethys belt. [ABSTRACT FROM AUTHOR]

Ethnographic accounts document widespread use of low-intensity surface fires by California's Native Americans to manage terrestrial resources, yet the effects of such practices on forest composition and structure remain largely unknown. Although numerous paleoenvironmental studies debate whether proxy interpretations indicate climatic or anthropogenic drivers of landscape change, available data sources (e.g., pollen, charcoal) are generally insufficient to resolve anthropogenic impacts and do not allow for hypothesis testing. We use a modeling approach with LANDIS-II, a spatially explicit forest succession and disturbance model, to test whether the addition of Native American-set surface fires was necessary to approximate vegetation change as reconstructed from fossil pollen. We use an existing 1,600-year pollen and charcoal record from Holey Meadow, Sequoia National Forest, California, as the empirical data set to which we compared modeled results of climatic and anthropogenic fire regimes. We found that the addition of anthropogenic burning best approximated fossil pollen-reconstructed vegetation change, particularly during periods of prolonged cooler, wetter periods coinciding with greater regional Native American activity (1550-1050 and 750-100 cal yr BP). For lightning-caused wildfires to statistically approximate the pollen record required at least twenty times more ignitions and 870 percent more area burned annually during the Little Ice Age (750-100 cal yr BP) than observed during the modern period (AD 1985-2006), a level of natural fire increase we consider highly improbable. These results demonstrate that (1) anthropogenic burning was likely an important cause of pre-Columbian forest structure at the site and (2) dynamic landscape models provide a valuable method for testing hypotheses of paleoenvironmental change. [ABSTRACT FROM AUTHOR]

Lignite samples from Nagaur district, Rajasthan, have been collected for petrographic and organic geochemical analyses following the pillar sampling method. The reflectance of Eu-Ulminite-B ranges from 0.20 to 0.49 with a mean of 0.33%Ro, putting them as “Low-Rank B” coal. Hydrogen index values imply type-III kerogen, while the values of Tmax (402 to 411°C) indicate that these coals are thermally immature. Gas chromatography data reveal the presence of n-alkanes from C14 to C33 with a predominance of odd n-alkanes over the even homologues. Pristane vs. phytane ratio indicates anoxic conditions during the deposition of the organic matter. Saturated fractions of studied lignites suggest a contribution from both conifers and angiosperms as source vegetation. [ABSTRACT FROM AUTHOR]

Integrated archaeological and paleoenvironmental investigations provide long-term perspectives on human-environment interactions. In the North Atlantic region, early human settlements were established in marginal agricultural environments and were susceptible to various environmental stressors. The Lofoten Islands have had an important role in the history of this region, particularly during the Iron Age, when Lofoten developed from pioneering agricultural settlements to a prominent node of power and trade under Viking chieftains. Iron Age developments in Lofoten were concurrent with significant natural environmental changes, including variations in climate and sea level. However, there has not been a comprehensive investigation of their influence on early settlements. The purpose of the study is to review Iron Age cultural developments in Lofoten using published archaeological data and paleoenvironmental records of past climate and sea-level change, and to present specific examples of the intersection of early human development and natural environmental changes. The findings show that climate changes probably influenced agricultural phases and that relative sea-level variations had important impacts on maritime developments. In conclusion, the findings demonstrate that human-environment interactions were significant factors in Lofoten’s history and the authors suggest specific areas for future research. [ABSTRACT FROM AUTHOR]

The Middle Ordovician Kelimoli Formation carbonate reservoirs in the northern Tianhuan area, Ordos Basin, China are main exploration targets. Subsurface core samples, logging, drilling and production data from the area were used to characterise the carbonate reservoir and to construct a genetic model for exploration. The sedimentary facies identified include trough-continental rise, upper-lower slope, platform margin reef-shoal, open platform and evaporation-restricted platform. The slope and platform margin facies are potential zones for high-quality reservoirs. Porosity in the study area comprises intergrain, intercrystal, intragrain and intracrystal pores, fractures and vughs. The Sr/Ba (0.40-4.87) and V/(V + Ni) (0.64-0.97) ratios indicate deposition in a brackish water-dominated environment under reducing conditions, associated with sea-level fluctuations during the deposition of the Kelimoli Formation. The Sr/Ba, V/(V + Ni), 87Sr/86Sr ratios, δ18O values and crystal texture of dolomite samples suggest that meteoric water was involved in the diagenetic fluid in the near-surface depositional environment. Isotopes (δ13C and δ18O) and trace elements (Fe and Mn) allowed the identification of seepage-reflux and mixed-water dolomitisation. The crystal textures of the samples consist of micritic, bioclastic and reefal limestones, and dolomite with gypsum, which were easily dissolved during the early diagenetic stage. The epidiagenetic stage was the key period for the development of high-quality reservoirs because of large-scale bedding-parallel karstification from meteoric water. The reservoir zones, dominated by partially filled and unfilled vughs, and fractures, are favourable exploration targets in the northern Tianhuan area. [ABSTRACT FROM AUTHOR]

Pollen analysis from Paisley Cave 2 (35LK3400), in Oregon has produced a record of climate change affecting the Summer Lake Sub-basin during a 7000-year period beginning at roughly 14,500 cal. yr. These sediments provide an opportunity to examine questions concerning human-environmental interaction at the end of the Pleistocene Epoch, during the Younger Dryas climatic event. The sediment deposits show a relatively unchanging early Holocene environment of predominantly xeric conditions with subalpine and marsh communities nearby. Additionally, there is little evidence of culturally significant use of any specific plant species. The data shows that the overall climatic conditions in the region were slightly cooler and perhaps wetter, just prior to the end of the Late Glacial, than today. These results provide important perspective on early settlement patterns and human ecology in the far western region of North America. [ABSTRACT FROM AUTHOR]

In this paper, we have studied a new micromammal site from the Sierra del Colmenar section (Elche, SE Spain), named Sierra del Colmenar 1A (SCO-1A), representing the uppermost levels of Messinian age of the Bajo Segura Basin. The sedimentary context of this locality corresponds to a costal lagoon with marine influence. The fossil site has yielded remains ofApodemusaff.gorafensis,Paraethomys meini,Apocricetus alberti,Occitanomys alcalai,Ruscinomyssp.,Eliomyscf.truci,Muscardinussp.,Parasorex ibericus, Prolagus michauxiand Soricidae indet. Based on this assemblage, we propose a Late Miocene age (MN13) for the locality SCO-1A, matching the previously inferred age for the stratigraphic unit in which the fossil site is situated. According to its faunal composition, we infer warm and humid climate conditions in the moment of formation of this locality, agreeing with the environmental conditions of the Messinian age in a parallic sedimentary context. [ABSTRACT FROM PUBLISHER]

Southern African late Quaternary research has developed rapidly during recent decades, with an increase in the range of proxies used, the inclusion of new field sites, and increased international collaboration and skills transfer. This has enabled recent meta-studies into the synoptic drivers of palaeoenvironmental shifts across the region, and of spatial variability in climatic and environmental changes. Expanded research has also highlighted uncertainties in the understanding of southern African palaeoenvironments, and the relationships with Northern Hemisphere analogues, encouraging on-going critical debate within the discipline. Given current concerns of climate change impacts on the natural environment, the spread of invasives, increased fire frequency, and anthropogenic influences on the natural environment, palaeoenvironmental data and inferences are increasingly being utilised outside of the palaeoenvironmental discipline, providing a valuable inter-disciplinary platform for global change science in the region. Relative to the size, landscape and climatic heterogeneity and resultant biome variability across southern Africa, the network of palaeoenvironmental study sites remains sparse, and arguably insufficient to resolve key debates. This paper critically reviews these spatial gaps in palaeoenvironmental knowledge, with a particular emphasis on the shortfalls of the current network of study sites and palaeoenvironmental records in resolving debates concerning latitudinal shifts of the Westerlies, conditions during the last glacial maximum and contemporaneous Northern and Southern Hemisphere climatic events. Southern African applications of palaeoenvironmental science in exploring ecological trait shifts, fire influences and anthropogenic impacts are briefly discussed, to facilitate the future identification of key sites, proxies, debates and applications in ongoing regional Quaternary work. [ABSTRACT FROM AUTHOR]

A new pollen record from south western Madhya Pradesh, central India provides a palaeoenvironmental record for the core monsoon zone (CMZ) of India. The 2m deep lacustrine sediment profile demonstrates that between ∼5679 and ∼4939 cal yr BP, open vegetation occurred in the region, indicative of a dry climate with reduced monsoonal precipitation. This was replaced by a mixed tropical deciduous forest under a warm and humid climate with increased monsoonal precipitation between ∼4939 to ∼3762 cal yr BP. From ∼3762 cal yr BP to the present day, a dense mixed tropical deciduous forest has existed under a warm and relatively more humid climate indicating a further increase in monsoonal precipitation. Cereal-based agricultural practice is evident during the most recent two phases. [ABSTRACT FROM AUTHOR]

Playa lake systems tend to be overlooked archives of paleoenvironmental change due to the likelihood of a short and intermittent record of deposition. Groundwater-fed wetlands associated with these climate-sensitive playas, however, preserve changes in hydrologic budget and are thus valuable archives for semiarid regions. This study examines the paleoecological record of a groundwater-fed wetland from Lake Solai, Kenya. Biological proxies are used to reconstruct paleoenvironmental change and climate impacts over the past millennium. Dry conditions persisted between CE 1115 and 1490, followed by wetter conditions during the Little Ice Age. Near surface sediments indicate increasing anthropogenic impact through pastoralism. [ABSTRACT FROM AUTHOR]

A recent publication (Levin and Ayres 2015) presented evidence for cyclical swiddening over a 700-year sequence at an old gardening site on Temwen Island, Pohnpei, Micronesia, using phytolith and microcharcoal evidence. Here, we corroborate this evidence by quantifying macroscopic charcoal from flotation occurring at the same site. Notably, the macrocharcoal provides evidence for burning in the immediate local area rather than the regional evidence that microcharcoal can provide. This method allows for a more robust interpretation of gardening microenvironments. [ABSTRACT FROM PUBLISHER]

The Pueblo I period was a time of tumultuous change throughout the Four Corners region. Long regarded as an era of gradual transition, it is now recognized by most authors as a discrete and decisive turning point in North American prehistory. Although this topic has been studied extensively in the central Mesa Verde area of southwestern Colorado, very little formal research has occurred for the early Pueblo era in southeast Utah. The high uplands area of Elk Ridge contains probably the greatest concentration of Pueblo I sites in this region. Cultural resource inventories on Elk Ridge itself, and an extensive published literature on nearby landforms such as Cedar Mesa, comprise a useful dataset for investigating the early Pueblo archaeology of southeast Utah. This paper presents a synthetic analysis of Pueblo I settlement patterning in the Elk Ridge area in terms of climatic and environmental factors. [ABSTRACT FROM AUTHOR]

Thirty-three modern surface samples were collected in the environmentally and climatologically contrasting regions of the Middle and High Atlas Mountains, Morocco. Samples representing forest and steppe montane environments (1935–2760 m above sea level) are clustered around study sites at Lake Tislit (High Atlas, semi-arid oro-Mediterranean bioclime) and Lake Sidi Ali and Michliffen (Middle Atlas, sub-humid montane Mediterranean bioclime). Good discrimination between regional pollen spectra is evident, with Middle Atlas samples reflecting higher arboreal cover (Cedrus and evergreen Quercus) and High Atlas samples with high abundances of non-arboreal taxa, including Artemisia and Fabaceae. These four taxa (Cedrus, evergreen Quercus, Artemisia and Fabaceae) are furthermore shown to be reliable indicators of local source vegetation within a 100 m2 quadrat, taking into account threshold abundances of 7%, 20%, 4% and 10%, respectively. Deciduous Quercus, Olea and Phillyrea show long-distance pollen dispersal across both regions, contributing to non-trivial arboreal pollen (AP) values of up to 35% (typically 20–30%) in the High Atlas spectra. In the Middle Atlas, AP values of 40 to 50% occur in open sampling locations and > 60% under forest canopy cover. These insights should be taken into account when interpreting ancient pollen spectra from regional lakes and bogs for palaeoenvironmental reconstruction. [ABSTRACT FROM AUTHOR]

Aves are represented by abundant fossil remains in Quaternary sites. Birds are well adapted to the environment they inhabit, so they make very good paleoenvironmental indicators for Quaternary sites. Here we analyse the avian remains from the Late Pleistocene (probably MIS3) site of Aguilón P-7 (AGP-7). The Pleistocene sediments fill up a shallow cave, which is located in the Zaragozan part of the Iberian Range, 55 km south of the city of Zaragoza. We have for the first time provided a taxonomic and taphonomic study of the avian assemblage of AGP-7, as well as a preliminary paleoenvironmental analysis based on these data. Nine avian taxa have been identified: Galliformes indet.,Lagopussp.,Aquila chrysaetos,Gyps fulvus, Passeridae indet.,Anthussp.,Prunella modularis,Sturnuscf.unicolorandCorvus monedula. The taphonomic analysis did not provide conclusive information. However, it suggests an accumulation of uneaten food remains by diurnal birds of prey. The identified taxa currently inhabit the Iberian Peninsula, populating woodland environments with rocky areas. They are found in areas with an oceanic climate, in contrast to the Mediterranean climate that now prevails in Aguilón. [ABSTRACT FROM AUTHOR]

The successful interpretation of continental ichnofossils is impeded by our limited knowledge of the burrows produced by modern continental animals. Actualistic studies of modern burrowing animals provide the data that make trace fossils invaluable to paleoecological and paleoenvironmental reconstructions. The goal of this project is to determine how well burrows produced by terrestrial arthropods, amphibians, and reptiles engaged in known behaviors under controlled environmental conditions can be differentiated on the basis of qualitative and quantitative morphology. The animals produced a diverse assemblage of shafts, tunnels, ramps, U-, J-, W-, Y-shaped and helical burrows, and mazeworks. The quantitative aspects of the burrow morphologies were compared using nonparametric similarity and distance indices as well as cluster analyses to determine if the burrow casts could be effectively differentiated based upon their tracemakers, behaviors, and environmental conditions. By using multiple properties of burrow morphology to compare the burrows statistically, many of the burrows were separated according to different behaviors and tracemakers, although overlaps did occur. Levels of similarity were highest amongst animals with similar morphologies, burrowing techniques, and behavioral patterns. Results from these analyses provide an assessment of our ability to reconstruct ancient soil ecosystems based on trace fossil morphology. By assembling a comprehensive analysis of the burrows of modern terrestrial animals, trace fossils may be described in a similar manner and compared directly to these modern analogs. This will be invaluable to improving the interpretation of tracemakers and behaviors. [ABSTRACT FROM AUTHOR]

This study is focused on the depositional model and paleoenvironmental distribution patterns of orbitolinids-rich microfacies in an Upper Cretaceous carbonate succession in the Kuh-e Mazar anticline in Kerman Province, Central Iran. Twelve microfacies indicating a tidal flat (including intertidal and supratidal) and an inner ramp (consisting of subtidal lagoon and orbitolinid–rudist barrier shoal) belonging to a shallow-water ramp-type carbonate platform were recognised. Generally, the orbitolinid associations in the carbonate ramp are indicative of shallow warm waters with normal salinity. The occurrence and abundance of thick or conical orbitolinids in both shoal and lagoon show that such associations were well adapted to different environmental conditions including different depth, substrate stability and water energy. The slightly discoidal, almost discoidal and discoidal forms were only present in the deeper depths of the environment including the lagoon with muddy and more stable substrates and lower water energy. However, the orbitolinids in the inner part of the carbonate ramp were scarce or almost absent in the deep inner to middle lagoon due to the deep restricted environmental conditions unfavourable for benthic marine life. [ABSTRACT FROM AUTHOR]

A geoarchaeological and paleobotanical study of a Paleoeskimo and Neoeskimo site was undertaken in order to reconstruct site-formation processes. The study site JfEl-10 is located on Igloo Island, in Diana Bay, on the southern shore of Hudson Strait. It contains a peat-mineral deposit situated between two successive beach crests, close to a small marsh. Samples from the edge of the site, which consists of a remarkable section of stratigraphy 60 cm thick that contains alternating brown organic beds and light-colored sand beds, were examined in the laboratory. Macrofossil data and pollen data were used to reconstruct the local and regional vegetation and to determine climatic changes over the past 1200 years. The geoarchaeological study includes the stratigraphy and the sedimentology of archaeological sediments. The evolution of the site followed three successive environmental phases, and the site was home to two distinct cultures. The first phase (from ca. 1200 to ca. 950 cal. yr B.P.) was characterized by cold and mesic conditions and the Dorset occupation. In the second phase, conditions became more humid beginning ca. 950 cal. yr B.P. and lasted for approximately 450 years. This period is marked by the arrival of Thule Inuit, who hunted marine mammals in the vicinity. Zooarchaeological information indicated a fall/winter occupation during the Thule Inuit period. The third phase corresponds with the onset of the Little Ice Age (A.D. 1500-1850) and associated cooling. During this time, the Thule Inuit abandoned the site. If the increased cooling caused an earlier freeze-up of Diana Bay, this may have prevented the movement of walrus to their haul-out island during fall. Additionally, the faster accumulation of thick ice would have limited the hunting of seals through their breathing holes. [ABSTRACT FROM AUTHOR]

The abundance, accessibility and value of limpets as a source of food and bait for coastal peoples have resulted in their high frequency in shell middens worldwide. The limpet Patella vulgata is found in middens from the Mediterranean to Norway, and morphometric and sclerochronological analyses of its shell can provide insight into harvesting patterns and paleoenvironmental variables valuable in reconstructing climate. Previous work with P. vulgata has relied on lines on the exterior of the shell, or on lines exiting on the shell surface in shell cross-section, as annual or sub-annual markers. Shell damage may compromise these lines and limit the use of some shells, but growth lines are also found in the better-preserved shell apex. We investigated whether the growth lines in the apex of P. vulgata from two locations in Northern Europe are annual using calcein-marking and recapture. Investigations were performed at one site in the Shetland Islands (UK) and at one site at the northern limit of P. vulgata's range in Northern Norway. We also used laser ablation to measure the concentration of minerals in the shells of two individuals from Shetland to determine if patterns of minerals suggested as bioproxies for temperature and productivity varied annually. All individuals deposited one growth line in the apex during their year in the field, and the lowest ratios of Sr/Ca and Ba/Ca and to a lesser extent Mg/Ca were coincident with annual lines on the shells from Shetland. Growth at both sites was modelled using the von Bertalanffy growth function, and apex growth was nearly five times faster in Shetland than in Norway, probably a result of differences in temperature between the two locations. [ABSTRACT FROM AUTHOR]

Non-pollen palynomorphs comprising algal remains, namelyBotryococcus,Chara,Concentricystis,Pediastrum,SpirogyraandZygnemaas well as fungal spores such as ascospore types,Alternaria,Cookeina,Curvularia,Diplodia,Glomus,Helminthosporium,Nigrospora, Microthyriaceae andTetraploa, well identified from the palynoslides prepared basically for the study of palaeovegetational succession and palaeoclimatic reconstructions, are discussed and illustrated from the late Quaternary sediments collected from southwestern Madhya Pradesh (India), which is regarded as one of the core monsoon zones of the Indian subcontinent.Botryococcusand zygospores of Zygnemataceae indicate warmer climate.Pediastrum–Botryococcusalternation may reflect colder–warmer climates.BotryococcusandPediastrummay also suggest oscillations in atmospheric precipitation. They could be sensitive indicators of salinity, pH, temperature and depth changes in palaeolagoons influenced by sea-level oscillations and climate.Charapoints to less oxygenated and hard water conditions. The record of fungal spores advocates the prevalence of a humid climate. [ABSTRACT FROM AUTHOR]

Ilha Grande is a Brazilian island that has a high vegetal biodiversity with a well-documented prehistoric human occupation but has few paleoenvironmental studies developed in this area. In view of this, multiproxy analysis of lagoonal sediments including radiocarbon dating were carried out on a 139 cm-long continental sediment core. The aim of our study was to recognise and explain environmental dynamics in this region during the Holocene (∼5200 cal yr BP). The palynomorphs indicate the continuous presence of Atlantic Forest under humid conditions during the last Holocene sea-level highstand, after 5200 cal yr BP. A phase of low palynomorph concentrations was followed by a marked increase in palynomorph accumulation and diversity which may be linked to the subsequent drop of the sea-level. Dinoflagellate cysts showed a higher accumulation at the base of the sediment core. The high accumulation of charcoal particles identified between approximately 3700 and 3000 cal years BP might indicate human activity related to the long-lasting bonfires kept burning by the inhabitants of the archaeological site of Ilhote do Leste. [ABSTRACT FROM AUTHOR]

Records of high resolution climate variability in the past are essential to understanding the climate change observed today. This is particularly true for Arctic regions, which are rapidly warming. Prior to instrumental data, proxy records can be extracted from highlatitude climate archives to provide critical records of past Arctic climate variability. Here, we investigate the feasibility of extracting records of climate and environmental variability from the skeleton of the crustose coralline alga Leptophytum foecundum from offshore the Sagavanirktok River in the Beaufort Sea. Although this alga forms an annually banded skeleton, age chronologies were established with difficulty due to the large uncalcified reproductive structures relative to low annual growth rates. Average measurements of skeletal Mg content, δ18Oalga values, and δ13Calga values were consistent among the analyzed specimens, but time series of these parameters only significantly correlated between two of the collected specimens for δ18Oalga. No clear trends in environmental variability explained the patterns in the skeletal geochemistry over time. This suggests that ambient seawater combined with freshwater from the Sagavanirktok River drives the geochemistry of L. foecundum at this site. Thus, coralline algal specimens located near variable sources of low-salinity waters are not ideal organisms to use as proxy archives. [ABSTRACT FROM AUTHOR]

The AR-1 layer, corresponding to the Escucha Formation (Lower Cretaceous) in the Santa Maria Mine of Ariño, has supplied rich and well-preserved macrofloral and palynological assemblages showing interesting data about both taphonomic and environmental conditions. This single layer is located in the Oliete Sub-Basin from the Maestrazgo Basin in northeastern Spain, and it represents one of the most outstanding single layer fossil sites in the world. This site shows abundant and diverse fauna containing exquisitely preserved vertebrate and invertebrate fossils (dinosaur bones, turtles, crocodiles, fishes, molluscs and ostracods) and also plant remains of Albian age. The assemblage is especially significant for dinosaur phylogenetic analysis. The sedimentary environment corresponds to a freshwater swamp plain with sporadic marine inputs within a deltaic–estuarine system under subtropical–tropical climate. [ABSTRACT FROM AUTHOR]

Why, when, and how people developed highly specialized marine economies remains the focus of considerable anthropological research. Study of maritime adaptations at high latitudes has potential to contribute to this debate because low biodiversity and increased resource seasonality at high latitudes made reliance on marine resources particularly risky. New research at the Cape Krusenstern site complex, located in northwest Alaska, offers a rare opportunity to study the evolution of maritime adaptations across the environmentally dynamic mid-to-late Holocene Arctic. Large-scale and systematic survey of this important site complex was undertaken to address questions about the timing and character of early Arctic coastal lifeways. Our research yielded direct dates of 4,200 years ago for the oldest occupation of the site complex and identified several new sites dating to between 4,200 and 2,000 years ago. Results support the existing settlement model, pointing to increased sedentism and local population only after 2,000 years ago. New data, however, indicate local population was much higher than previously established and that coastal occupation was sustained over long periods of time despite considerable mid-to-late Holocene paleoenvironmental variability. Together, these findings raise new questions about the evolution of maritime adaptations at high latitudes. [ABSTRACT FROM AUTHOR]

Four ichnospecies,Dimorphichnusisp.,Monomorphichnusisp. A,M. isp. B and cf.Nereitesisp., are described from the upper part of the ?middle Cambrian Pantapinna Sandstone, Balcoracana Creek, Flinders Ranges, South Australia. They occur on the base of fluted sandstones, thus indicating a short period of open marine influence within what has generally been interpreted as a fluvial to marginal marine succession. [ABSTRACT FROM AUTHOR]

This paper investigates several wedge structures formed in continental deposits covering marine sediments deposited during MIS 5 along the central Patagonian coast of Argentina. The size and surface microtexture characteristics of the infilling sediments are consistent with a depositional environment dominated by aeolian transport. Fragments of Andean volcanic rocks (glass shards) in the wedge-fill suggest long-distance transport via a westerly component of wind direction. The wedges are interpreted as products of deep seasonal frost action in frozen ground, which produced open cracks that filled rapidly with partially non-local aeolian sediments. Many wedges cross cut carbonate crusts that formed under permafrost conditions in coastal Patagonia. The radiocarbon dating of carbonate crusts yielded an age of 25-27 kyr bp, while wedge-fill sediments are OSL dated to 14 670 ± 750 yr bp. This indicates that ground wedge formation occurred during a cold event (the Antarctic Cold Reversal period) that interrupted the permafrost degradation following the Last Glacial Maximum. [ABSTRACT FROM AUTHOR]

The hyper-arid climate of Ouargla area (Northern Sahara of Algeria) is important in the field of the paleoenvironmental reconstitution. This paper investigates the importance of palaeolake sediments as significant terrestrial archives for studying Quaternary climate changes. Through morphological and mainly micromorphological investigations of the studied sites (Sabkha of Ouargla and palaeolake of Mellala), we noted the fluctuation of climate between arid and more humid conditions during Quaternary. Some pedofeatures have recorded these environmental changes. The studied calcareous crusting has a lacustrine origin when precipitations were more important. The clay coatings around the quartz grains indicate an old origin and different geochemical conditions that led to their dissolution. Lenticular gypsum crystals were formed from groundwater saturated with Ca2+andions. Calcite pseudomorphs after lenticular gypsum crystals indicate changes in local climatic parameters. Gypsum crusts can be explained by formation under wet climatic conditions in a lagoonal environment. Black and gray layers indicate evolution of organic matter at a wetter period. This paper highlights an unknown palaeolake which can be useful for the comprehension of the ecological past of the Sahara. The comparison between this palaeolake and other Saharan palaeolakes has allowed us to assign it to a probable active period between 10000 and 4000 years B.P. [ABSTRACT FROM PUBLISHER]

The primitive deer (subfamily Lagomerycinae)LagomeryxandStephanocemasare characterized primarily by their palmate antlers. Two lagomerycines,Lagomeryx manai, sp. nov., andStephanocemas rucha, are described for the first time from Q and K coal layers of the late middle Miocene (13.4–13.2 Ma) Mae Moh Basin in northern Thailand. A species-level phylogeny of theLigeromeryx-Lagomeryxclade, based on cranial appendages, reconstructsLagomeryx manai, n. sp., as a derived species ofLagomeryx, sister group ofLagomeryx complicidens. This study suggests that the large species ofLagomeryxare restricted geographically to Asia and dispersed to Southeast Asia at the latest during late middle Miocene, where they are represented byLagomeryx manai, n. sp. The paleoenvironmental studies of five Mae Moh mammalian taxa, a cervid (Lagomeryx manai, n. sp.), an indeterminate bovid, a suid (Conohyus thailandicus), a rhinoceros (Gaindatheriumsp.), and a proboscidean (Stegolophodonsp.), investigated with stable carbon and oxygen isotope analyses of tooth enamel, indicate that the Mae Moh mammals inhabited a wide range of habitats from woodlands to grasslands in a C3-plant-dominated environment. The new species ofLagomeryxseems to have been living in an open environment, contrary to its European relatives. The serial isotopic samples also support that Mae Moh herbivores probably lived in a low-seasonal climate during the late middle Miocene of northern Thailand. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free atwww.tandfonline.com/UJVP [ABSTRACT FROM AUTHOR]

The objective of this study is to determine fine-scale spatial and temporal trends in screen temperature, lapse rates, and inversions associated with the Great African Escarpment wall. Particular attention is focused on the characteristics of near-surface-temperature lapse rates, their variability associated with particular synoptic conditions, and environmental implications such as for modeling climate projections in topographic- and climatic-specific high mountain regions. Hourly temperature data were logged on northeast- and southeast-facing slopes over 12 months in 2001, in the high Drakensberg Escarpment of southern Africa, at a range of elevations including: 2650, 2900, and 3200 m a.s.l. High spatial and temporal variations in lapse rates are recorded and illustrated. A relatively low mean annual lapse rate of -0.42 °C 100 m-1 between 2650 and 2900 m a.s.l. doubles to -0.84 °C 100 m-1 between 2900 and 3200 m a.s.l. The frequent westerlies and tropical temperate troughs provide for high lapse rates ( -- 0.91 °C 100 m-1), which are likely responsible for the relatively high annual average lapse rate of - 0.63 °C 100 m-1. Quanti-fying the fine-scale temperature trends has important implications for better understanding site-specific paleoenvironmental signatures and for projecting future climate scenarios and associated bio- and geosystem responses. [ABSTRACT FROM AUTHOR]

Byssate bivalves can be attached to hard substrates by byssal threads. Dissolution of the substrate to which they are attached may leave superficial bioerosion traces. This study reports the scars produced by byssus ofMytilus edulisandAulacomya atrarecorded in shells ofOstrea puelchana.Oyster valves were cut and gold-sputtered prior to scanning electron microscope observation. Each byssal thread leaves a characteristic scar on shells substrate. They etch an irregular trace on the substrate which may reach a diameter of several centimeters. These etching-traces comprise shallow round/oval holes of variable number and placement. A bundle of pits corresponding to fibers that compose the thread core was identified in the interior of each hole. We suggest that this trace could be included in the ethological class Fixichnia. The description of this trace would allow adjusting the composition of fossil assemblages and therefore paleoenvironmental interpretations in those cases in which mytilid shells have not been preserved. The recognition of this trace along with other ones of tracemakers with reotaxis or positive phototaxis could be useful in inferring the life habit of fossil biogenic substrates and in reconstructing their taphonomic history. [ABSTRACT FROM PUBLISHER]

The Bass Basin, southeastern Australia, is a moderately explored, Late Cretaceous to late Cenozoic, intra-cratonic rift system. Despite the success of hydrocarbon exploration in the adjacent Otway and Gippsland basins, attempts to locate significant hydrocarbon reservoirs in the Bass Basin have been disappointing, with only one major gas accumulation found in the centre of the basin since drilling began in 1965. However, owing to the basin's tectonostratigraphic characteristics, which typically support the accumulation of significant reservoirs, the Bass Basin remains a viable target for hydrocarbon exploration. In this study, a detailed, fine-scale, stratigraphic framework, employing spore–pollen biozones as an age control of potentially suitable hydrocarbon source, reservoir and seal facies has been constructed to provide a better understanding of the basin's paleoenvironmental evolution. Data from various sources, including well completion reports, drill core, cuttings descriptions and seismic sections were collated and analysed. Data from 18 wells were used in order to construct two cross-sections; one extending from the northwest to southeast along the basin and the other extending northeast to southwest. Up to 12 biozones were correlated between the wells. Key stratigraphic units and biozones were then correlated with hydrocarbon source, reservoir and seal and were traced along the basin. New results demonstrate that from the late Maastrichtian the depositional system was dominated by a large tidal inlet or lagoonal system situated between a marine influence towards the northwest and fluvial processes operating in the far southeast. Major hydrocarbon source facies are mainly located within the middle to upper Eocene, upperM. diversustoP. asperopolusbiozones in the Eastern View Coal Measures and are generally concentrated in the northwest section of the basin. Potential reservoir and seal facies also appear to be thickest in this region. This new research reveals that from an exploration perspective, risk increases towards the southeast as the concentration of source facies diminishes, and the thickness of potential reservoir and seal facies decreases. [ABSTRACT FROM PUBLISHER]

Hystricognathous rodents are among the most common members of African mammal faunas of the mid-Paleogene, but their record has so far remained limited to North and northeast Africa. Here we report the first Paleogene record of hystricognaths from the Atlantic margin of North Africa. The fossils come from the westernmost part of the Sahara, east of the Dakhla peninsula, Morocco, from estuarine deposits dating to the earliest Oligocene (Dakhla level C2[DAK C2]). Several tens of isolated teeth plus three jaw fragments document seven species of hystricognaths (Gaudeamuscf.aslius, G.cf.hylaeus, Phenacophiomys occidentalis, gen. et sp. nov.,Birkamysaff.korai, Mubhammys atlanticus, sp. nov.,Neophiomys minutus, sp. nov., and ?Phiocricetomyssp.). Despite the extensive east-west geographic distance, the majority of hystricognath taxa recorded in DAK C2document primarily close relatives of taxa that are known from a latest Eocene Egyptian locality (L-41) and from early Oligocene localities of both Egypt and Libya. This highlights the widespread east-west distribution of hystricognaths across North Africa, a distribution that reflects the existence of roughly similar tropical environmental conditions in northern latitudes of Africa at that time. The presence of seven hystricognath species plus five anomaluroid species in sympatry during the earliest Oligocene demonstrates that rodents were particularly diverse near the global cooling recorded at the Eocene-Oligocene transition. We describe and compare the species and new species of hystricognaths with their sub-coeval counterparts from northern and northeastern Africa and then discuss the paleobiogeographic and paleoenvironmental implications of that discovery. http://zoobank.org/urn:lsid:zoobank.org:pub:4041680F-65A0-41D5-AF97-D6115A656F15 Citation for this article: Marivaux, L., S. Adnet, M. Benammi, R. Tabuce, J. Yans, and M. Benammi. 2017. Earliest Oligocene hystricognathous rodents from the Atlantic margin of northwestern Saharan Africa (Dakhla, Morocco): systematic, paleobiogeographical, and paleoenvironmental implications. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1357567. [ABSTRACT FROM AUTHOR]

ABSTRACT—Whereas ‘biological site fidelity’ refers to the regular reuse of a favored locale (e.g., breeding ground or nest) by an individual animal, ‘paleontological site fidelity’ typically refers to repeated use of a nesting locality by a herd or species over geologic time scales. Two new Cretaceous specimens from the Two Medicine Formation of Montana, U.S.A., and the Liantoutang Formation of Zhejiang, China, each preserve two closely superimposed clutches of the egg formPrismatoolithus.These eggs belong to the Troodontidae, small theropod dinosaurs sharing a close ancestry with Aves. In both specimens, eggs of a lower clutch are truncated at a level below what would normally preserve in an undisturbed hatched clutch. These traces differ from past examples of dinosaur site fidelity in (1) the close or cross-cutting relationship of the clutches, (2) the precise overlay of clutch atop clutch, and (3) the implication of nest reuse and, thus, site fidelity on an ecologic rather than geologic scale and at approximately the individual rather than species level. Given the likely extended occupation of troodontid nesting sites by attending adults, factors such as nesting success and territoriality may, in addition to favorable substrates, have influenced the behaviors recorded by these specimens. The arrangements of eggs as clutches within the geologic record represent trace fossils. Thus, they record past in situ behavior, providing important insight into dinosaur nesting. In addition, they can serve as independent indicators of substrate conditions and sedimentary history, potentially refining our understanding of paleoenvironments. [ABSTRACT FROM PUBLISHER]