A5000936194- Geology and Paleoclimatology Research
- Archaeology and ancient environmental studies
- Climate change and permafrost
- Isotope Analysis in Ecology
- Maritime and Coastal Archaeology
- Nuclear Physics and Applications
- Pleistocene-Era Hominins and Archaeology
- Atmospheric and Environmental Gas Dynamics
- Marine and environmental studies
- Tree-ring climate responses
- Cryospheric studies and observations
- Ecology and biodiversity studies
- Geological Studies and Exploration
- X-ray Spectroscopy and Fluorescence Analysis
- Geological formations and processes
- Paleopathology and ancient diseases
- Hydrology and Watershed Management Studies
- Mass Spectrometry Techniques and Applications
- Archaeology and Natural History
- Soil Carbon and Nitrogen Dynamics
- Evolution and Paleontology Studies
- Ecology and Vegetation Dynamics Studies
- Pacific and Southeast Asian Studies
- Cultural Heritage Materials Analysis
- Fire effects on ecosystems
University of Ottawa
2015-2024
University of Arizona
2020-2021
Institut de l'Information Scientifique et Technique
2020-2021
Carleton University
2011-2014
Master's College
2013
An annually laminated succession in Crawford Lake, Ontario, Canada is proposed for the Global boundary Stratotype Section and Point (GSSP) to define Anthropocene as a series/epoch with base dated at 1950 CE. Varve couplets of organic matter capped by calcite precipitated each summer alkaline surface waters reflect environmental change global local scales. Spheroidal carbonaceous particles nitrogen isotopes record an increase fossil fuel combustion early 1950s, coinciding fallout from nuclear...
Abstract The A.E. Lalonde accelerator mass spectrometer (3MV, HVEE) was commissioned in early 2014 at the University of Ottawa (Canada). radiocarbon sample preparation laboratory spent better part undertaking a quality control program, establishing pretreatment protocols, and streamlining processing. In fall 2014, first unknown samples were accepted year operation well over 1000 targets (~60% unknowns) analyzed. Here, we present an overview processing protocols results from routinely...
We examined late Holocene (ca. 3300 yr BP to present-day) climate variability in the central Northwest Territories (Canadian Subarctic) using a diatom and sedimentological record from Danny's Lake (63.48ºN, 112.54ºW), located 40 km southwest of modern-day treeline. High-resolution sampling paired with robust age model (25 radiocarbon dates) allowed for examination both lake hydroecological conditions (30-year intervals; diatoms) changes watershed (12-year grain size records) over Holocene....
Abstract New computer-controlled, semi-automatic systems were designed and built for CO 2 purification graphitization at the A.E. Lalonde Accelerator Mass Spectrometry (AMS) Laboratory with consideration user friendliness high throughput. The stainless steel vacuum lines are orbitally welded to ensure clean seams low memory. insulated ovens plug-in electrodes provide a hazard-free environment operators. closed-loop cooling system circulating low-viscosity Dynalene –40°C provides highly...
ABSTRACT Sample preparation techniques for radiocarbon analysis of dissolved inorganic carbon (DIC) and organic (DOC) in freshwater, as well CO 2 CH 4 gas mixtures are presented. Focused efforts have been on developing a robust low-background wet oxidation extraction method DOC following routine methods developed stable isotope adapted ( 14 C) analysis. DIC (by acidification) oxidation) converted to pre-baked septum-fitted borosilicate bottles, where the resulting is extracted from headspace...
Abstract Agricultural soils contribute significantly to global CO 2 emissions. Soils can be both a sink and source depending on vegetation cover the physical‐chemical characteristics of soil environment. This study uses new 14 C dating approach elucidate physical geochemical properties that drive production transport in cultivated noncultivated drainage ditch environments. As expected, fluxes decrease with depth. Relating depth‐specific subsurface radiocarbon ( ) atmospheric scenario...
ABSTRACT Fewer than 200 radiocarbon ( 14 C) dates with secure contextual information are available for Cuba, making it challenging to reconstruct Caribbean indigenous population dynamics, their identities and interactions. In this paper, we discussed 21 accelerator mass spectrometry (AMS) C from two mounds (M1 M2) at the Playa del Mango site (Granma province, Cuba), traditionally associated Banwaroid stone tool tradition. The ΔR calculated was –132.0 ± 176 –164.0 68. chronology of burials...
The unprecedented environmental changes resulting from anthropogenic activities initiated during the Great Acceleration of mid-20th century can be traced using radiocarbon analysis. cosmogenic isotope 14C, which is produced in atmosphere, well-known as geochronological tool applied to archives last 55 thousand years. However, 200 years, natural signal 14C atmosphere and connected reservoirs (biosphere, ocean, soils, etc.,) has been perturbed by human activities. Two effects are observed: a...
ABSTRACT Observation of the ion source generated background has been an area focus during our routine analytical work. It is noted that results very-low-ratio samples are dependent upon particular procedures for measurement using present-day Cs + sputter sources. When measured without excessive fluxes and interleafing with other higher-ratio references, accelerator mass spectrometry (AMS) sensitivity can be somewhat improved. In some cases, it appears possible to assess old radiocarbon ( 14...
Here we describe the oldest, most complete wolf pup (Canis lupus) mummy discovered to date: “Zhur”, as she was named by local indigenous Tr’ondëk Hwëch’in community in 2016 Yukon, Canada, and is with skin, fur, other soft tissues. We infer that Zhur died ~57,000 years ago ~7 weeks old at death. Her mitochondrial genome falls within a clade comprising ancient Beringian Russian genomes, isotopic analyses show her diet composed of mostly aquatic resources. Although mummies like will...
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