A5076711635- Geology and Paleoclimatology Research
- Paleontology and Stratigraphy of Fossils
- Geological and Geochemical Analysis
- Geomagnetism and Paleomagnetism Studies
- Geological and Geophysical Studies
- Astro and Planetary Science
- Methane Hydrates and Related Phenomena
- Geological formations and processes
- Planetary Science and Exploration
- Isotope Analysis in Ecology
- earthquake and tectonic studies
- Geochemistry and Geologic Mapping
- Geological Studies and Exploration
- Geophysics and Gravity Measurements
- Hydrocarbon exploration and reservoir analysis
- Cryospheric studies and observations
- Marine Biology and Ecology Research
- Pleistocene-Era Hominins and Archaeology
- Coral and Marine Ecosystems Studies
- Oceanographic and Atmospheric Processes
- Evolution and Paleontology Studies
- Magnetic and Electromagnetic Effects
- Geochemistry and Elemental Analysis
- Marine and environmental studies
- Winter Sports Injuries and Performance
Princeton University
2015-2024
Princeton Public Schools
2023
University of Victoria
2022
California Institute of Technology
1986-2022
Dartmouth College
2022
Environmental Institute
2018
Massachusetts Institute of Technology
1986-2015
Woodrow Wilson International Center for Scholars
2009
Centre de Géosciences
2009
Harvard University
1999-2006
Research Article| September 01, 2005 Toward a Neoproterozoic composite carbon-isotope record Galen P. Halverson; Halverson 1Department of Earth and Planetary Sciences, Harvard University, 20 Oxford Street, Cambridge, Massachusetts 02138-2902, USA, Department Earth, Atmospheric, Institute Technology, Building 54-1126, 02139, USA Search for other works by this author on: GSW Google Scholar Paul F. Hoffman; Hoffman 2Department Daniel Schrag; Schrag Adam C. Maloof; Maloof A. Hugh N. Rice...
We review recent observations and models concerning the dynamics of Cryogenian global glaciation their biological consequences.
The Neoproterozoic was an era of great environmental and biological change, but a paucity direct precise age constraints on strata from this time has prevented the complete integration these records. We present four high-precision U-Pb ages for rocks in northwestern Canada that constrain large perturbations carbon cycle, major diversification depletion microfossil record, onset Sturtian glaciation. A volcanic tuff interbedded with glacial deposits, dated at 716.5 million years ago, is...
Research Article| November 01, 2010 The earliest Cambrian record of animals and ocean geochemical change Adam C. Maloof; Maloof † 1Department Geosciences, Princeton University, Guyot Hall, Washington Road, Princeton, New Jersey 08544, USA †E-mail: maloof@princeton.edu Search for other works by this author on: GSW Google Scholar Susannah M. Porter; Porter 2Department Earth Science, University California, Santa Barbara, California 93106, John L. Moore; Moore Frank Ö. Dudás; Dudás 3Department...
We describe an ultra-sensitive atomic magnetometer using optically-pumped potassium atoms operating in spin-exchange relaxation free (SERF) regime. demonstrate magnetic field sensitivity of 160 aT/Hz$^{1/2}$ a gradiometer arrangement with measurement volume 0.45 cm$^3$ and energy resolution per unit time $44 \hbar$. As example new application enabled by such we measurements weak remnant rock magnetization as function temperature on the order 10$^{-10}$ emu/cm$^3$/Hz$^{1/2}$ temperatures up...
We present a δ 13 C record from the Anti-Atlas mountains of Morocco and place it in context detailed regional tectonostratigraphy. litho- chemostratigraphic temporal framework using precision UPb zircon geochronology ashes interbedded with same carbonate units that provide data. The variations occur on wide range time scales, suggesting different mechanisms are involved, including non-steady state release isotopically depleted carbon reservoirs short (<100 000 years) scales changes...
Global carbon cycle perturbations throughout Earth history are frequently linked to changing paleogeography, glaciation, ocean oxygenation, and biological innovation. A pronounced carbonate carbon-isotope excursion during the Ediacaran Period (635 542 million years ago), accompanied by invariant or decoupled organic values, has been explained with a model that relies on large oceanic reservoir of carbon. We present matter data demonstrate no decoupling from approximately 820 760 ago complete...
The last interglacial stage (LIG; ca. 130–115 ka) provides a relatively recent example of world with both poles characterized by greater-than-Holocene temperatures similar to those expected later in this century under range greenhouse gas emission scenarios. Previous analyses inferred that LIG mean global sea level (GSL) peaked 6–9 m higher than today. Here, we extend our earlier work perform probabilistic assessment variability within the highstand. Using terminology for probability...
Satellite imagery offers an efficient and cost‐effective means of estimating water depth in shallow environments. However, traditional empirical algorithms for calculating often are unable to account varying bottom reflectance, therefore yield biased estimates certain benthic We present a simple method that is grounded the physics radiative transfer seawater, but made more robust through calibration individual color‐to‐depth relationships separate spectral classes. Our cluster‐based...
Significance We have discovered 2 major oceanic anoxic events (OAEs) in the early Cambrian at time when animals markedly diversified. present a multiproxy constraint on global biogeochemical cycles to show that these events, contrast most younger OAEs, could been driven by declining atmospheric O levels, plausibly set off appearance of bioturbating animals. Pulses animal appearances may occurred different times continents, but last pulse after OAEs and we predict higher marine productivity...
Abstract Two separate and distinct diamictite‐rich units occur in the mixed carbonate‐siliciclastic Polarisbreen Group, which comprises top kilometer of >7 km Neoproterozoic strata northeast Svalbard archipelago. The platformal succession accumulated on windward, tropical to subtropical margin Laurentia. older Petrovbreen Member is a thin glacimarine diamictite that lacks cap carbonate. It contains locally derived clasts overlies regional karstic disconformity was directly preceded by...
Research Article| September 01, 2006 Combined paleomagnetic, isotopic, and stratigraphic evidence for true polar wander from the Neoproterozoic Akademikerbreen Group, Svalbard, Norway Adam C. Maloof; Maloof 1Department of Earth Planetary Sciences, Harvard University, 20 Oxford Street, Cambridge, Massachusetts 02138, USA Search other works by this author on: GSW Google Scholar Galen P. Halverson; Halverson Joseph L. Kirschvink; Kirschvink 2Division Geological California Institute Technology...
Research Article| July 01, 2010 Constraints on early Cambrian carbon cycling from the duration of Nemakit-Daldynian–Tommotian boundary δ13C shift, Morocco Adam C. Maloof; Maloof 1Department Geosciences, Princeton University, Princeton, New Jersey 08544, USA Search for other works by this author on: GSW Google Scholar Jahandar Ramezani; Ramezani 2Department Earth, Atmospheric and Planetary Sciences, Massachusetts Institute Technology, Cambridge, 02139, Samuel A. Bowring; Bowring David Fike;...
On the mid‐Atlantic Coastal Plain of United States, Paleocene sands and silts are replaced during Paleocene‐Eocene Thermal Maximum (PETM) by kaolinite‐rich Marlboro Clay. The clay preserves abundant magnetite produced magnetotactic bacteria novel, presumptively eukaryotic, iron‐biomineralizing microorganisms. Using ferromagnetic resonance spectroscopy electron microscopy, we map magnetofossil distribution in context stratigraphy carbon isotope data identify three magnetic facies clay: one...
Research Article| April 01, 2015 Stratigraphy and geochronology of the Tambien Group, Ethiopia: Evidence for globally synchronous carbon isotope change in Neoproterozoic Nicholas L. Swanson-Hysell; Swanson-Hysell 1Earth Planetary Science Department, University California, Berkeley, California 94720, USA Search other works by this author on: GSW Google Scholar Adam C. Maloof; Maloof 2Department Geosciences, Princeton University, Princeton, New Jersey 08544, Daniel J. Condon; Condon 3Natural...
The supercontinent Rodinia is hypothesized to have been assembled and positioned in tropical latitudes by the early Neoproterozoic Era. Paleomagnetic data from limestones of Svalbard basaltic dikes South China interpreted record rapid changes paleogeography driven true polar wander that may rotated association with ∼800 Ma Bitter Springs carbon isotope event. To further constrain test proposed rotations, we developed sequence- chemo-stratigraphically constrained paleomagnetic Formation...
Significance We present stable carbon isotope ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:msup><mml:mrow><mml:mi>δ</mml:mi></mml:mrow><mml:mrow><mml:mn>13</mml:mn></mml:mrow></mml:msup></mml:math> C) data from modern carbonate sediment that require a decoupling of the cycles in global ocean versus shallow shelves. This realization is important because, for first 97% Earth history, many inferences about paleoclimate and seawater chemistry rely on...
Research Article| April 26, 2018 The arc of the Snowball: U-Pb dates constrain Islay anomaly and initiation Sturtian glaciation Scott MacLennan; MacLennan 1Department Geosciences, Princeton University, Princeton, New Jersey 08544, USA Search for other works by this author on: GSW Google Scholar Yuem Park; Park 2Earth Planetary Sciences Department, University California, Berkeley, California 94720, Nicholas Swanson-Hysell; Swanson-Hysell Adam Maloof; Maloof Blair Schoene; Schoene Mulubrhan...
Abstract Tides and Earth‐Moon system evolution are coupled over geological time. Tidal energy dissipation on Earth slows rotation rate, increases obliquity, lunar orbit semi‐major axis eccentricity, decreases inclination. core‐mantle boundary within the Moon decrease inclination, eccentricity axis. Here we integrate backwards for 4.5 Ga with orbital dynamics explicit ocean tide models that “high‐level” (i.e., not idealized). To account uncertain plate tectonic histories, employ Monte Carlo...