Although the data are too limited to permit the formal naming of any new polarity epochs or events, four polarity transitions have been identified: The loss of absolute resolution of K-Ar dating in older rocks indicates that the use of well defined stratigraphic successions to identify and date polarity transitions will be important in the study of Pliocene and older reversals.
The Murchison Widefield Array is designed to measure the fluctuations in the 21cm emission from neutral hydrogen during the Epoch of Reionisation. The new hex configuration is explicitly designed to test the predicted increase in sensitivity of redundant baselines. However the challenge of the new array is to understand calibration with the new configuration.
We have developed two new pipelines to reduce the hex data, and will compare the results with previous datasets from the Phase 1 array. We have now processed 80 hours of data refining the data analysis through our two established Phase 1 pipelines. This proposal requests as much observing time as possible in semester A to 1 obtain a comparable hex dataset to test the sensitivity and systematic limits with redundant arrays, 2 establish the optimal observing strategy for an EoR detection, and 3 continue to explore observational strategies in the three EoR fields to advise the design of SKA-low experiments.
Due to the proposed changes in the array during the upcoming semester, we have not requested a specific number of hours, but will optimise our observing program as availability of the telescope becomes clear. We note that this observing proposal implements the key scientific program that can benefit from the new hex configuration.
The theme of phenomenology and quantum physics is here tackled by examining some basic interpretational issues in quantum physics. One key issue in quantum theory from the very beginning has been whether it is possible to provide a quantum ontology of particles in motion in the same way as in classical physics, or whether we are restricted to stay within a more limited view of quantum systems, in terms of complementary but mutually exclusive phenomena.
However, there are other interpretations especially David Bohm's that seem to re-establish the possibility of a mind-independent ontology at the quantum level. We will show that even such ontological interpretations contain novel, non-classical features, which require them to give a special role to "phenomena" or "appearances", a role not encountered in classical physics.
Kira Janene Holt
Published by Elsevier Ltd. Late Paleocene glyptosaur Reptilia: The discovery of South Carolina osteoderms is significant because they expand the late Paleocene geographic range of glyptosaurines eastward from the US midcontinent to the Atlantic Coastal Plain and provide one of the few North American records of these lizards inhabiting coastal habitats. This discovery also brings to light a possibility that post- Paleocene expansion of this group into Europe occurred via northeastward migration along the Atlantic coast of North America.
Physics In the time before the first seconds of the Universe, or the Planck Epoch , the laws of physics as we know them break down; the predictions of General Relativity become meaningless as distance physics models predict that during this epoch the four fundamental forces were combined into one unified. Foraminiferal stratigraphy of Ranikot Paleocene of Pakistan. The sedimentary deposits of Pakistan are divided into three distinct basins: The Lower Indus basin is further divided into two parts; the northern part is the Sulaiman Province, and the southern part is known as Kirthar Province.
The tertiary stratigraphy of Kirthar Province is conspicuous for its characteristic lithostratigraphic units. The Ranikot Group was divided by Cheema et al in into three distinct lithostratigraphic units: The Khadro and Lakhra formations are marine, characterized by foraminiferal assemblages. The characteristic planktonic forms are: Globigerina triloculinoides Plummer, Globorotalia pseudobulloids Plummer , G.
The diagnostic forms of larger foraminifera are: The planktonic foraminifera were assigned to Globorotali trinidadensis, G. This paper extends in two directions the results of prior work on generalized linear covariance analysis of both batch least-squares and sequential estimators. The first is an improved treatment of process noise in the batch, or epoch state, estimator with an epoch time that may be later than some or all of the measurements in the batch. The second is to account for process noise in specifying the gains in the epoch state estimator.
We establish the conditions under which the latter estimator is equivalent to the Kalman filter. Ten new determinations on volcanic extrusions in the Sierra Nevada with potassium-argon ages of 3. Thermomagnetic experiments and mineralogic studies fail to provide an explanation of the opposing polarities in terms of mineralogic control, but rather suggest that the remanent magnetization reflects reversals of the main dipole field of the earth.
All available radiometric ages are consistent with this field-reversal hypothesis and indicate that the present normal polarity epoch N1 as well as the previous reversed epoch R1 are 0. Chronostratigraphy of the mammal-bearing Paleocene of South America. Land mammal faunas of Paleocene age in the southern Andean basin of Bolivia and NW Argentina are calibrated by regional sequence stratigraphy and magnetostratigraphy.
All known South American Paleocene land mammal faunas are thus between Late Paleocene and are here assigned to the Riochican Land Mammal Age, with four subages from oldest to youngest: Peligrian, Tiupampian, Itaboraian, Riochican s. An interchange event for continental taxa between North and South America is identified between Impact ejecta at the Paleocene -Eocene boundary. Extraterrestrial impacts have left a substantial imprint on the climate and evolutionary history of Earth. A rapid carbon cycle perturbation and global warming event about 56 million years ago at the Paleocene -Eocene P-E boundary the Paleocene -Eocene Thermal Maximum was accompanied by rapid expansions of mammals and terrestrial plants and extinctions of deep-sea benthic organisms.
Here, we report the discovery of silicate glass spherules in a discrete stratigraphic layer from three marine P-E boundary sections on the Atlantic margin. Distinct characteristics identify the spherules as microtektites and microkrystites, indicating that an extraterrestrial impact occurred during the carbon isotope excursion at the P-E boundary. Geomagnetic reversal in brunhes normal polarity epoch.
The magnetic stratigraphly of seven cores of deep-sea sediment established the existence of a short interval of reversed polarity in the upper part of the Brunches epoch of normal polarity. The reversed zone in the cores correlates well with paleontological boundaries and is named the Blake event. Observing the epoch of galaxy formation.
Significant observational progress in addressing the question of the origin and early evolution of galaxies has been made in the past few years, allowing for direct comparison of the epoch when most of the stars in the universe were forming to prevailing theoretical models. There is currently broad consistency between theoretical expectations and the observations, but rapid improvement in the data will provide much more critical tests of theory in the coming years. Upper Paleocene and lowermost Eocene angiosperm pollen biostratigraphy of the eastern Gulf Coast and Virginia.
Strata comprising most of the upper Paleocene in eastern North America are divided into two new pollen zones, the Carya and Platycarya platycaryoides Interval Zones. Pollen data have proven to be important for correlations between Alabama-western Georgia and eastern Mississippi and between the eastern Gulf Coast and Virginia. Migration of tropical plant taxa from the Caribbean to the Gulf Coast began at least 4 m. The Terminal Paleocene Extinction Event, accompanied by a distinct pulse of plant immigration from Europe, began several hundred thousand years before the end of the Paleocene.
Administering an epoch initiated for remote memory access. Methods, systems, and products are disclosed for administering an epoch initiated for remote memory access that include: During these epochs , early stars and black holes heated and ionized the IGM, introducing fluctuations in 21 cm emission. HERA is designed to characterize the evolution of the 21 cm power spectrum to constrain the timing and morphology of reionization, the properties of the first galaxies, the evolution of large-scale structure, and the early sources of heating.
Currently, 19 dishes have been deployed on site and the next 18 are under construction. After reviewing the current state of the art in foreground mitigation, we use the delay-spectrum technique to motivate high-level performance requirements for the HERA instrument. Finally, we summarize the schedule and status of the project. We conclude by suggesting that, given the realities of foreground contamination, current-generation 21 cm instruments are approaching their sensitivity limits. HERA is designed to bring both the sensitivity and the precision to deliver its primary science on the basis of proven foreground filtering techniques, while developing new subtraction techniques to unlock new capabilities.
The result will be a major step toward realizing the widely recognized scientific potential of 21 cm cosmology. New paleomagnetic and potassium-argon dating measurements have been made of basalt flows from Nunivak Island, Alaska, with the following results. Geologic history and palynologic dating of Paleocene deposits, western Rock Springs uplift, Sweetwater County, Wyoming. During the latest Cretaceous or earliest Paleocene , a northwest-southeast trending anticline developed in the area of the present Rock springs uplift in southwestern Wyoming.
This ancestral structure was eroded to a surface of fairly low relief on which a paleosol developed. The surface was formed on the Upper Cretaceous Almond Formation throughout the study area. In the early middle Paleocene P3 palynomorph zone , topographic lows on the erosion surface were infilled by alluvial deposits that accumulated in channel, floodplain, and backswamp environments. An organic-rich facies contains numerous coal beds and is middle to late Paleocene in age P3 to P5 zones. The assemblage of pollen that defines the late middle Paleocene P4 zone is absent from the area suggesting a hiatus, although no lithologic break was observed at this boundary.
The younger organic-poor facies begins in the late Paleocene P5 zone and continues to the top of the studied sequence. This change in facies has been used to map the contact between the Fort Union Formation of Paleocene age in this area, and the Wasatch Formation which was though to be of Eocene age.
This study demonstrates that, as currently mapped, the lower part of the Wasatch Formation is Paleocene in age. Stratigraphically higher parts of the Wasatch, which presumably contain rocks of latest Paleocene P6 zone and earliest Eocene age, were not studied. Dinosaur teeth from Paleocene channel fills have been interpreted as indicating dinosaur survival into the Paleocene. However, enormous potential for reworking exists because these records are restricted to large channel fills that are deeply incised into Cretaceous strata. Identification of reworked fossils is usually equivocal.
This problem is illustrated by the Black Spring Coulee channel fill, a dinosaur-bearing Paleocene deposit in the upper Hell Creek Formation of eastern Montana. In this example, the reworked nature of well-preserved dinosaur bones is apparent only after detailed sedimentological and palynological analysis. To date, reports of Paleocene dinosaurs do not fulfill any of these criteria. Thus, the proposal that dinosaurs persisted into the Paleocene remains unsubstantiated.
HERA leverages the operation of the PAPER and MWA telescopes to explore techniques and designs required to detect the primordial HI signal in the presence of systematics and radio continuum foreground emission some four orders of magnitude brighter.
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With this understanding, we are now able to remove foregrounds to the limits of our sensitivity, culminating in the first physically meaningful upper limits. Building on this, the next stage of HERA incorporates a 14m diameter antenna element that is optimized both for sensitivity and for minimizing foreground systematics. Arranging these elements in a compact hexagonal grid yields an array that facilitates calibration, leverages proven foreground removal techniques, and is scalable to large collecting areas.
With its sensitivity and broader frequency coverage, HERA can paint an uninterrupted picture through reionization, back to the. Mars - Epochal climate change and volatile history. The epochal climate change and volatile history of Mars are examined, with special attention given to evidence for and mechanisms of long-term climate change. Long-term climate change on Mars is indicated most directly by the presence, age, and distribution of the valley networks. They were almost certainly formed by running water, but it seems more likely that they were formed by groundwater sapping than by rainfall.
It is argued to be physically plausible that a higher early intensity of surface insolation caused by a CO2 greenhouse effect could have overcompensated for an early weak sun and raised temperatures to the freezing point near the equator under favorable conditions of obliquity and eccentricity.
This could account for the morphological changes.
The Large Synoptic Survey Telescope LSST , a next generation astronomical survey, sited on Cerro Pachon in Chile, will provide an unprecedented amount of imaging data for studies of the faint optical sky. The LSST system includes an 8. This system will enable about 10, sq. The measured properties of newly discovered and known astrometric and photometric transients will be publicly reported within 60 sec after closing the shutter.
The resulting hundreds of petabytes of imaging data for about 40 billion objects will be used for scientific investigations ranging from the properties of near-Earth asteroids to characterizations of dark matter and dark energy. For example, simulations estimate that LSST will discover about 1, quasars at redshifts exceeding 7; this sample will place tight constraints on the cosmic environment at the end of the reionization epoch. Evidence from Polecat Bench in Northwestern Wyoming.
Many important environmental events in the geological past were first recognized by their effects on the associated biota, and this is true for the Paleocene -Eocene Thermal Maximum or PETM global greenhouse warming event, which happened 55 million years before present. In the Southern Ocean, PETM carbon and oxygen isotope anomalies were found to coincide with a major terminal- Paleocene disappearance or extinction of benthic foraminiferans.
Linking the two records, marine and continental, resolved a long-standing disagreement over competing definitions of the Paleocene -Eocene epoch boundary, and more importantly indicated that the PETM greenhouse warming event was global. Dwarfing of herbivorous mammals can be interpreted as a response to elevated atmospheric CO2. The origin of modern orders of mammals including Artiodactyla, Perissodactyla, and Primates 'APP' taxa is more complicated and difficult to explain but the origin of these orders may also be a response, directly or indirectly, to PETM warming.
We now know from Polecat Bench and elsewhere in North America that the biotic response to PETM greenhouse warming involved the appearance of at least two new mammalian faunas distinct from previously known Clarkforkian mammals of the upper or late Paleocene and previously known Wasatchian mammals of the lower or early Eocene.
Three stages and ages of the former are known Cf-1 to Cf-3 and seven stages and ages of the latter are known Wa-1 to Wa-7 , each occupying about a hundred meters of strata representing a half-million years or so of time. Between the standard Clarkforkian and Wasatchian faunal zones is an initial 'Wa-M' faunal zone of only five or so meters in thickness and something on the order of 20 thousand years of geological time.
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The Wa-M fauna includes the first. We selected two samples: The formal errors on these weighted parallax solutions are mostly between 4 and 10 mas. A few of these are found to be within 10 pc. Many of these new nearby stars display a total proper motion of less than mas yr Paleocene coal deposits of the Wilcox Group, Northeast Texas. This area forms the northwestern flank of the East Texas Basin Figure 2 , the axis of which separates northeast Texas from the Sabine uplift structural area.
Epoch Lifetimes in the Dynamics of a Competing Population. We propose a dynamical model of a competing population whose agents have a tendency to balance their decisions in time. The model is applicable to financial markets in which the agents trade with finite capital, or other multiagent systems such as routers in communication networks attempting to transmit multiclass traffic in a fair way. We find an oscillatory behavior due to the segregation of agents into two groups. Each group remains winning over epochs. The aggregation of smart agents is able to explain the lifetime distribution of epochs to 8 decades of probability.
The existence of the super agents further refines the lifetime distribution of short epochs. The Hydrogen Epoch of Reionization Array HERA is a radio telescope dedicated to observing large scale structure during and prior to the epoch of reionization. Once completed, HERA will have unprecedented sensitivity to the cm signal from hydrogen reionization. This poster will present time- and frequency-subtraction methods and results from a preliminary analysis of the noise characteristics of the nineteen-element pathfinder array.
Cyclic transgressive and regressive sequences, Paleocene Suite, Sirte basin, Libya. The Farrud lithofacies represent the main reservoir rock of the Ghani oil field and Western Concession Eleven of the Sirte basin, Libya. Eight microfacies are recognized in the Farrud lithofacies in the Ghani field area: The Paleocene suite of the Farrud lithofacies generally shows a prograding, regressive sequence of three facies: Source rocks were primarily organic-rich shales overlying the Farrud reservoir rock.
Porosity and permeability were developed in part by such processes as dolomitization, leaching, and fracturing in the two progradational, regressive carbonate facies. Hydrocarbons were trapped by a supratidal, anhydrite cap rock. A new reference section for palynostratigraphic zonation of Paleocene rocks in the Rocky Mountain region. A biostratigraphic palynostratigraphic zonation of Paleocene rocks was established in the northeastern Wind River Basin near Waltman, Natrona County, Wyoming, in and subsequently applied extensively by various workers throughout the Rocky Mountain region.
Because the original study on which the zonation was based was proprietary, precise details about the locations of the two reference sections and the samples on which the zonation was based were not published and are no longer retrievable. Therefore, it is useful although not required to designate formally a new reference section for the Paleocene biozones. Accordingly, exposures of Paleocene and associated strata within and west of the Castle Gardens Petroglyph Site in Fremont County, Wyoming, in the east-central part of the Wind River Basin, were selected for this purpose.
At this location, composite stratigraphic sections encompassing m of strata were measured, described, and sampled. Productive samples yielded characteristic Maastrichtian palynomorphs from the lower part of the sampled interval and diagnostic species of the six palynological biozones zones widely known as P1 lower Paleocene through P6 upper Paleocene , through an interval of about m.
The Paleocene biozones are present in the same consistent stratigraphic order in the Castle Gardens area as observed in the study and subsequent studies throughout the Rocky Mountain region. In accordance with the North American Stratigraphic Code, the historical background is presented; intent to establish the Castle Gardens reference section is declared; the category, rank, and formal names of biostratigraphic units within it are specified; and the features of the biozonation are described, including biozone boundaries, ages, and regional relations. Occurrences of biostratigraphically significant palynological species within each biozone in the reference section are tabulated, and presence of these and other species in correlative.
A Paleocene lowland macroflora from Patagonia reveals significantly greater richness than North American analogs. Few South American macrofloras of Paleocene age are known, and this limits our knowledge of diversity and composition between the end-Cretaceous event and the Eocene appearance of high floral diversity. We report new, unbiased collections of compression specimens from the Paleocene Salamanca Formation ca. Our samples reveal considerably greater richness than was previously known from the Paleocene of Patagonia, including 36 species of angiosperm leaves as well as angiosperm fruits, flowers, and seeds; ferns; and conifer leaves, cones, and seeds.
The floras, which are from siltstone and sandstone channel-fills deposited on low-relief floodplain landscapes in a humid, warm temperate climate, are climatically and paleoenvironmentally comparable to many quantitatively collected Paleocene floras from the Western Interior of North America. The cause of the dis parity is unknown but could involve reduced impact effects because of greater distance from the Chicxulub site, higher latest Cretaceous diversity, or faster recovery or immigration rates.
Paleocene decapod Crustacea from northeastern Mexico: Additions to biostratigraphy and diversity. New decapod specimens from mid- Paleocene shallow marine deposits of NE Mexico represents an important addition to the diversity, paleobiogeography and evolution of the Crustacea record. Species reported from the mid- Paleocene Selandian assemblage of the Porters Creek Formation Alabama , are correlatable to the decapod species from NE Mexico in age, size and systematic composition.
The erymid lobster Enoploclytia gardnerae Rathbun, is represented by several carapaces and chelae remains. One isolated palm of Callianassidae is included. Numerous carapaces of Linuparus wilcoxensis Rathbun, are described, representing the most abundant lobster. A new record for the raninid Notopoides sp. New raninids, Claudioranina latacantha sp. Cyrtorhininae are also part of this assemblage. Paraverrucoides alabamensis Rathbun, , and Tehuacana americana Rathbun, are represented by several carapaces exhibiting intraspecific morphological variation.
Effects of rapid global warming at the Paleocene -Eocene boundary on neotropical vegetation. We investigated the tropical forest response to this rapid warming by evaluating the palynological record of three stratigraphic sections in eastern Colombia and western Venezuela. We observed a rapid and distinct increase in plant diversity and origination rates, with a set of new taxa, mostly angiosperms, added to the existing stock of low-diversity Paleocene flora.
There is no evidence for enhanced aridity in the northern Neotropics. The tropical rainforest was able to persist under elevated temperatures and high levels of atmospheric carbon dioxide, in contrast to speculations that tropical ecosystems were severely compromised by heat stress. Hydrological Process of Martian Surface in Hesperian epoch. It is considered that the Mars in Noachian ecoch was much warmer temperature than current condition, with atmosphere and ocean supported by its magnetic actiity. Several valley which seems to be developed by ancient hydrological processes are obsered in Martian surface, is being considered to be built long time before.
Some fluvial fun was formed during the following Hesperian epoch , which is considered as much cooler and drier than Noachian epoch. In this study, we applied Hydro-debris 2D model into Martian surface in Hesperian epoch in order to try develping surface vallay formation throughout hydrological processes.
Sediment transport and associated small-scale debris-flow occurrence may be the key for valley formation, where might be the micro-habitable zone. Into the Epoch of Galaxy Formation. A first analysis of the new observations indicates that "evolved" galaxies were already present when the Universe was only 4 billion years old.
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This information is of great importance to our understanding of how the matter in the early Universe condensed and the first galaxies and stars came into being. While in the nearby Universe evolved galaxies are preferentially located in denser environments such as groups and clusters of galaxies, little is currently known about the distribution in space of such objects at early cosmic epochs. Such observations are beyond the capability of the infrared cameras installed on the world's 4-m class telescopes.
With ISAAC , it is possible to obtain "deep" NIR images in an unprecedentedly wide field of view, covering a sky area about 7 times larger than with the best instruments previously available on very large telescopes. Such observations also benefit greatly from the very good optical quality provided by the active optics control of the VLT, as well as the excellent Paranal site. The Story of Informatization. Informatization is a term of Japanese provenance denoting major systemic change from the application of information technology.
Proposes a theory of post-war informatization focusing on information services in libraries, specifically computerized information retrieval. Describes four electronic epochs: Extraterrestrial 3He in Paleocene sediments from Shatsky Rise: Constraints on sedimentation rate variability. We attempt to constrain the variability of the flux of extraterrestrial 3He in the Paleocene by studying sediments from Shatsky Rise Ocean Drilling Program, ODP Leg that have tight orbital age control.
The total helium in the sediments can be explained as a binary mixture of terrestrial and extraterrestrial components. We determine a constant extraterrestrial 3He flux of 5. This value is identical within error to those for the late Paleocene in sediments from the northern Pacific and the Weddell Sea. Bulk sediment MARs derived using a constant extraterrestrial 3He flux respond to climate-forced carbonate preservation cycles and changes in eolian flux over the late Paleocene. This is the first direct evidence for significant changes in dust accumulation in response to eccentricity forcing during a greenhouse climate interval.
It has been proposed that ocean acidification - a decrease in the pH and carbonate saturation state of the water as a result of dissolved carbon dioxide in sea water - occurred in both the shallow and deep marine realms. Ocean acidification would have had a devastating impact on the benthic ecosystem, and has been proposed as the cause of decreased carbonate deposition in marine sections and coral reef collapse during the late Paleocene.
To date, however, the only physical evidence of Paleocene -Eocene ocean acidification has been shown for offshore sites i. Several sites in the Kras region of Slovenia, has been found to contain apparent erosion surfaces coeval with the Paleocene -Eocene Boundary. We have investigated these potentially acidified horizons using petrography, stable carbon isotopes, cathodoluminescence, and elemental mapping.
These datasets will inform whether the horizons formed by seafloor dissolution in an acidified ocean, or are due to subaerial exposure, or burial diagenesis i. Physical erosion and diagenesis can easily be ruled out based on field relationships and petrography, but the other potential causes must be analyzed more critically. Oldest known euarchontan tarsals and affinities of Paleocene Purgatorius to Primates.
Earliest Paleocene Purgatorius often is regarded as the geologically oldest primate, but it has been known only from fossilized dentitions since it was first described half a century ago. The dentition of Purgatorius is more primitive than those of all known living and fossil primates, leading some researchers to suggest that it lies near the ancestry of all other primates; however, others have questioned its affinities to primates or even to placental mammals.
Here we report the first to our knowledge nondental remains tarsal bones attributed to Purgatorius from the same earliest Paleocene deposits that have yielded numerous fossil dentitions of this poorly known mammal. Three independent phylogenetic analyses that incorporate new data from these fossils support primate affinities of Purgatorius among euarchontan mammals primates, treeshrews, and colugos. Astragali and calcanei attributed to Purgatorius indicate a mobile ankle typical of arboreal euarchontan mammals generally and of Paleocene and Eocene plesiadapiforms specifically and provide the earliest fossil evidence of arboreality in primates and other euarchontan mammals.
Postcranial specializations for arboreality in the earliest primates likely played a key role in the evolutionary success of this mammalian radiation in the Paleocene. A search for changing look quasars in second epoch imaging. Over nearly two decades, the Sloan Digital Sky Survey has compiled a catalog of over half a million confirmed quasars. During that period approximately ten percent of these objects have been spectroscopically observed in two or more epochs over baselines of ten or more years.
This led recently to the discovery of the largest change in luminosity ever before observed in a quasar. The dimming emission was a reflection of very significant changes in continuum and broad line properties, the source had effectively transitioned from a Type I quasar to a Type II AGN. Since then several more "changing look" quasars have been discovered in multi- epoch SDSS spectroscopy.
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Among them are objects with rising and falling luminosities, appearing and disappearing broad lines. The origin of this behavior is still very uncertain, currently favored is the scenario in which an accreting black hole is simply starved of fuel. Other plausible scenarios include flaring due to stellar tidal disruption close to the black hole or large changes in accretion flow, which can occur during transitions between radiatively efficient and inefficient accretion regimes.
Monitoring of larger numbers of changing look quasars will help to elucidate these ideas. In this poster, we report on the progress of a pilot study in which we hope to learn how to select changing look quasars in multi- epoch imaging. This will allow us to take advantage of the entire SDSS quasar catalog rather than just the ten percent of objects with multi- epoch spectroscopy. Comparing archival SDSS and more recent Legacy Survey imaging over ten-year baselines we select objects whose photometry is consistent with the large changes in luminosity expected in changing look quasars.
We aim to build up a catalog of both transitioned and transitioning objects for future monitoring. In this paper, we introduce a novel entropy measure, termed epoch -based entropy. This measure quantifies disorder of EEG signals both at the time level and spatial level, using local density estimation by a Hidden Markov Model on inter-channel stationary epochs.
The investigation is led on a multi-centric EEG database recorded from patients at an early stage of Alzheimer's disease AD and age-matched healthy subjects. We investigate the classification performances of this method, its robustness to noise, and its sensitivity to sampling frequency and to variations of hyperparameters. The measure is compared to two alternative complexity measures, Shannon's entropy and correlation dimension.
The classification accuracies for the discrimination of AD patients from healthy subjects were estimated using a linear classifier designed on a development dataset, and subsequently tested on an independent test set. Furthermore, it was shown to be more stable to hyperparameter variations, and less sensitive to noise and sampling frequency disturbances than the other two complexity measures.
Frieling, Joost; Huurdeman, Emiel P. These reconstructions have revealed a large discrepancy between temperature proxy data and climate models in this region, suggesting a crucial error in model, proxy data or both. To resolve the origin of this discrepancy, detailed reconstructions are needed from both sides of the Tasmanian Gateway. Here we present new stratigraphic data for upper Paleocene and lower Eocene strata from the Otway Basin, southeast Australia, on the north west side of the Tasmanian Gateway.
We analyzed sediments recovered from exploration drilling Latrobe-1 drill core and outcrop sampling Point Margaret and performed high-resolution carbon isotope geochemistry of bulk organic matter and dinoflagellate cyst dinocyst and pollen biostratigraphy on sediments from the regional lithostratigraphic units, including the Pebble Point Formation, Pember Mudstone and Dilwyn Formation. Pollen and dinocyst assemblages are assigned to previously established Australian pollen and dinocyst zonations and tied to available zonations for the SW Pacific.
Based on our dinocyst stratigraphy and previously published planktic foraminifer biostratigraphy, the Pebble Point Formation at Point Margaret is dated to the latest Paleocene. The globally synchronous negative carbon isotope excursion that marks the Paleocene -Eocene boundary is identified within the top part of the Pember Mudstone in the Latrobe-1 borehole and at Point Margaret. However, the high abundances of the. The Paleocene -Eocene interval is well known as a time of climatic transitions, especially hyperthermals associated with disturbances in the carbon cycle that are used as proxies for impacts of projected anthropogenic global climate change.
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The disconformity is developed on a thick, kaolinitic paleosol, which we interpret as a mature Oxisol that supported tropical rainforest vegetation as evidenced by associated well preserved leaf fossils. The nature of the paleosol at the disconformity led us to hypothesize that the strata might contain evidence of the Paleocene Eocene Thermal Maximum PETM. Results showed no evidence of the negative excursion characteristic of the PETM. Instead, we found a gradual upsection enrichment that we interpret as the positive trend characteristic of the lower Paleocene Carbon Isotope Maximum PCIM.
This is reasonable based on published biostratigraphy and absolute ages from elsewhere in the Naheola Formation. Further analyses will be performed to determine whether the PCIM trend continues throughout the remainder of the core. Also, the PCIM is associated with a gradual warming trend as indicated by previously published stable oxygen isotopes from benthic foraminifera.
Studying successive ME paleosols throughout the PCIM may yield information about the impacts of gradual atmospheric warming on soils and associated terrestrial systems. Geochemistry and depositional environments of Paleocene -Eocene phosphorites: We review the characteristics of phosphorites deposited in three areas: Comprehensive new bulk rock elemental data are presented, together with complementary mineralogical and mineral chemical results.
Carbonate fluorapatite francolite constitutes the dominant mineral phase in the deposits. Phosphorite samples are enriched in Cd, Sr, U, rare-earth elements and Y, together with environmentally diagnostic trace elements that provide detrital Cr, Zr , productivity Cu, Ni, Zn and redox Mo, V proxies. Suboxic bottom-water conditions predominated, with suboxic to anoxic porewaters accompanying francolite precipitation. Phosphorite deposition occurred under increasingly arid climate conditions, accompanying global Paleocene -Eocene warming.
The Northern Basins show the strongest Tethys Ocean influence, with surface seawater rare-earth element signatures consistently developed in the phosphorites. Bed-scale compositional variation indicates relatively unstable environmental conditions and episodes of sediment redeposition, with varying detrital supply and a relatively wet local climate. Glauconitic facies in the Northern Basins and the more isolated evaporite-associated phosphorites in the dryer Eastern Basins display the greatest diagenetic influences.
The phosphorite - organic-rich marl - diatom-bearing porcelanite facies association in the Gafsa-Metlaoui Basin represents the classic coastal upwelling trinity. Modified Tethyan waters occurred within the Basin during phosphorite deposition, with decreasing marine productivity from NW to SE evidenced by systematically falling enrichment factors for Cu, Ni, Cd and Zn in the phosphorites. Productivity declined in concert with increasing basin isolation during the deposition of the commercial phosphorite beds in the latest Paleocene to earliest.
A Paleocene penguin from New Zealand substantiates multiple origins of gigantism in fossil Sphenisciformes. One of the notable features of penguin evolution is the occurrence of very large species in the early Cenozoic, whose body size greatly exceeded that of the largest extant penguins. Here we describe a new giant species from the late Paleocene of New Zealand that documents the very early evolution of large body size in penguins.
Several plesiomorphic features place the new species outside a clade including all post- Paleocene giant penguins. It is phylogenetically separated from giant Eocene and Oligocene penguin species by various smaller taxa, which indicates multiple origins of giant size in penguin evolution. That a penguin rivaling the largest previously known species existed in the Paleocene suggests that gigantism in penguins arose shortly after these birds became flightless divers. Our study therefore strengthens previous suggestions that the absence of very large penguins today is likely due to the Oligo-Miocene radiation of marine mammals.
Three palynological studies of the post-impact section are currently underway. A few samples from the Early Paleocene have also been examined but organic microfossil preservation is quite poor. Samples from this core are the oldest palynological record from the Yucatan peninsula. Terrestrial palynomorph assemblages will be used to reconstruct paleoclimatological conditions throughout this time period.
Floral response to hyperthermal events in the IODP core will be compared with records from other Gulf of Mexico and Caribbean sections. In addition to the biological and paleoclimatological implications of this research, age control from foraminiferal and nannofossil biostratigraphy, paleomagnetism, and radiometric dating will provide a chronological framework for the terrestrial pollen biostratigraphy, with applications to hydrocarbon exploration in the Wilcox Formation and age equivalent sections in the Gulf of Mexico.
The term 'anthropocene' has gained enormous popularity among scientists who believe we are in a global phase distinguished by the extensive and lasting impacts of social activities on Earth's sedimentary record and vital systems. Beyond its widespread informal use, a working group of the International Union of Geological Sciences seeks to formalize the term to name a new geological epoch , implying that the Holocene epoch has ended.
If human-caused mass extinction and other ecological catastrophes are serious harms, ethical responses are required. Instead, the move to formalize the idea of an 'anthropocene' epoch treats dire ethical warnings as an opportunity to redefine the current dangerous situation as a new status quo. Have we met our responsibilities to protect Holocene Earth? This presentation will focus on the ethical implications of using the power and discourse of geology to demote Holocene ecological states from their role as the foundational benchmarks for guiding and assessing human relationships with nature and other species.
Have geoscientists adequately consulted the biological, ecological and social sciences before declaring the end of the Holocene epoch? Upon what do we base environmental ethics if the Holocene is considered past history? I will also examine the ethical dimensions of naming the so-called 'anthropocene', asking: Are the phenomena identified with the 'anthropocene' nuclear fallout, mass species endangerment, ocean acidification, fossil fuel pollution, deforestation, mining definitive accomplishments of the human species?
A detailed summary of the data used, analyses performed, modeling techniques employed, and results obtained in the course of the Epoch World Magnetic Modeling effort are given. Charts and tables related to the World Magnetic Model WMM for the Earth's main field and secular variation in Mercator and polar stereographic projections are presented along with useful tables of several magnetic field components and their secular variation on a 5-degree worldwide grid. Latest Paleocene lithologic and biotic events in neritic deposits of southwestern New Jersey.
Significant lithologic and biotic changes occur in these strata near the top of the Paleocene. Global warming, increased precipitation, and other oceanographic and climatic events that have been recognized in high-latitude, deep-oceanic deposits of the latest Paleocene also influenced mid-latitude, shallow-marine, and terrestrial environments of the western North Atlantic. The diverse, well-preserved calcareous nannofossil flora that is present throughout the entire New Jersey boundary section accurately places these events within the uppermost part of the upper Paleocene Zone NP 9.
Several rapid but gradational changes occur within a 1. Pollen was sparse in the New Jersey drill holes, but terrestrial sporomorph species in Virginia exhibit increased turnover rates at a correlative level. Foraminiferal assemblages and lithology indicate that relative sea level rose in New Jersey at the same time as these late Paleocene events occurred in late Biochron NP 9.
The higher sea levels influenced sediment type and absolute abundance of planktonic foraminifers in the deposits. Above the initial increase of kaolinite in the upper part of Zone NP 9, the kaolinite percentage continues to increase, and the maximum kaolinite value occurs in the uppermost part of Zone NP 9.
There are few changes in either the sediments or the. We are testing the alternative hypothesis that the carbon cycle perturbation resulted from wildfires affecting the extensive peatlands and coal swamps formed in the Paleocene. Accounting for the CIE with terrestrial organic carbon rather than methane requires a significantly larger net release of fossil carbon to the ocean-atmosphere, which may be more consistent with the extreme global warming and ocean acidification characteristic of the Paleocene -Eocene Thermal Maximum PETM.
While other researchers have noted evidence of fires at the Paleocene -Eocene boundary in individual locations, the research presented here is designed to test the "wildfire hypothesis" for the Paleocene -Eocene boundary by examining marine sediments for evidence of a global increase in wildfire activity. Such fires would produce massive amounts of soot, widely distributed by wind and well preserved in marine sediments as refractory black carbon.
We expect that global wildfires occurring at the Paleocene -Eocene boundary would produce a peak in black carbon abundance at the PETM horizon. We are using the method of Gelinas et al. This method involves the chemical and thermal extraction of non-refractory carbon followed by combustion of the residual black carbon and measurement as CO2. Our instrumentation goals include: The array is being built and evaluated in stages at the Green Bank Observatory in West Virginia with deployment of the full instrument in Western Australia.
We present results from an eight-station deployment in Green Bank and four-station deployment in Western Australia, including phase and amplitude calibration, RFI mitigation and removal, full sky maps, and wide-field snapshot imaging. We have discovered new ways to improve our system's stability and sensitivity from these early experiments, and are applying these concepts to a element array in Green Bank in early and a element array in Western Australia later in Is there another coincidence problem at the reionization epoch? The cosmological coincidences between the matter and radiation energy densities at recombination as well as between the densities of matter and the cosmological constant at the present time are well known.
We point out that, moreover, the third intersection between the energy densities of radiation and the cosmological constant coincides with the reionization epoch. To quantify the statistical relevance of this concurrence, we compute the Bayes factor between the concordance cosmology with free Thomson scattering optical depth and a model for which this parameter is inferred from imposing a match between the time of density equality and the epoch of reionization. This is to characterize the potential explanatory gain if one were to find a parameter-free physical connection.
We find a very strong preference for such a concurrence on the Jeffreys scale from current cosmological observations. We furthermore discuss the effect of the choice of priors, changes in reionization history, and free sum of neutrino masses. We also estimate the impact of adding intermediate polarization data from the Planck High Frequency Instrument and prospects for future 21 cm surveys. In the first case, the preference for the correlation remains substantial, whereas future data may give results more decisive in pro or substantial in contra of it.
Finally, we provide a discussion on different interpretations of these findings. In particular, we show how a connection between the star-formation history and the cosmological background dynamics can give rise to this concurrence. Observational and Theoretical Constraints. The latest radiometric data confirm that the main phases of magma extrusion of both DT and NAIP were concentrated over relatively short intervals Shallow marine ostracode turnover in response to environmental change during the Paleocene -Eocene thermal maximum in northwest Tunisia.
Two outcrop sections spanning the Paleocene -early Eocene boundary in the Sidi Nasseur-Wadi Mezaz area in northwest Tunisia provided rich ostracode assemblages, yielding 26 species of which three are newly described: Reymenticosta bassiounii, Reymenticosta nasseurensis and Buntonia?
The recorded ostracode fauna and associated foraminifera reflect deposition in a coastal to inner neritic environment. Many of the recorded taxa have a wide geographic distribution throughout the Middle East and North Africa. A correspondence is also observed with West African faunas, especially in the early Eocene fauna.
These taxa seem to have originated in West Africa during the Paleocene and migrated northwards during the late Paleocene to early Eocene. Sea-level change and decrease in oxygenation associated with the Paleocene -Eocene thermal maximum PETM caused the local disappearance of the South Tethyan Paleocene fauna represented by Paracosta kefensis morphotype-A , Paracosta aff.
B Esker, Loxoconcha saharaensis, Buntonia sp. Simultaneously, a new but poorly diverse Afro-Tethyan fauna, mainly represented by Alocopocythere attitogonensis and Buntonia? After the PETM, diversity increased again as various taxa e. Bairdia aegyptiaca, Reticulina lamellata and Aegyptiana duwiensis re appeared. Dipole of the Epoch of reionization cm signal. The motion of the Solar System with respect to the cosmic rest frame modulates the monopole of the epoch of reionization cm signal into a dipole. This dipole has a characteristic frequency dependence that is dominated by the frequency derivative of the monopole signal.
Most importantly, the direction of the cosmic velocity vector is known exquisitely well from the cosmic microwave background and is not aligned with the galaxy velocity vector that modulates the foreground monopole. Well written and interesting. As with almost every e-book I have read, there are a few errors that seem to be part of the program and not part of the book. Maybe it was just my reader, but several pages repeated. There was a problem loading comments right now. There's a problem loading this menu right now. Learn more about Amazon Prime.
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