Dr. Dallas Abbott
Adjunct Research Scientist , Marine Geology & Geophysics , Lamont-Doherty Earth Observatory (LDEO) , The Earth Institute
61 Route 9W
PO Box 1000
Palisades, NY 10964
Dallas Abbott has worked in the areas of Marine Geology, Geophysics, Precambrian Geology, and Impact Geology. Over the past 13 years, Abbott has developed the microtechniques necessary to study the fine debris from oceanic impacts. Deep-sea impacts pose several problems. The first is a very restricted sample size compared to subaerial impacts. The second is a lack of large quartz grains in most settings, resulting in a reduced abundance of or no shocked quartz. Her collaborators and she have developed microtechniques to study oceanic impacts. They use the scanning electron microscope and analyses of thin sections of tiny grains to find and confirm impact ejecta.
Abbott has also learned how to separate out particulates from ice cores at ages of suspected Holocene impacts. They measured the highest concentration ever of marine diatoms in the GISP2 ice core. The diatoms are low latitude and originate from a source on a continental shelf with high biological productivity. Several other types of dust, including micrometer sized CaCO3 crystals, accompany the diatoms. The latter may have caused a dust veil and climate downturn that lasted for 18 months (Feb. 536 to June 537 AD). Some dust with both substantial Ni and K may be impact ejecta. They are still developing these microtechniques but they have already yielded some important scientific results. By combining proxies for continental dust with historical accounts of unusual dust storms, they have managed to date their ice core samples to within a calendar year. This allows us to tie our scientific results into the historical record-a mix that should attract students of both Earth Science and History. One accomplishment is documenting oldest primary native Fe ever found. Abbott and her collaborators found 1.6 Ga native Fe in the Chaibasa Formation in India. This is the worlds oldest primary native Fe by over a billion years.
- Consortium for Ocean Leadership IODP-USIO Support of 2014 Summer Intern at LDEO
- REU Site: Interdisciplinary Cutting-Edge Research though the Analysis of Global Data
- REU SITE: Research Experience for Undergraduates: Analyzing Global Databases
- REU Site: Research Experience for Undergraduates: Analyzing Global Databases
- Support of two IODP Summer Interns (Shared support for two students)
31 PUBLICATIONS ON COLUMBIA | ACADEMIC COMMONS
- What Are the Origins of V-Shaped (Chevron) Dunes in Madagascar? The Case for Their Deposition by a Holocene Megatsunami
- New historical records and relationships among 14C production rates, abundance and color of low latitude auroras and sunspot abundance
- New historical records and relationships among ¹⁴C production rates, abundance and color of low latitude auroras and sunspot abundance
- Calendar-year dating of the Greenland Ice Sheet Project 2 (GISP2) ice core from the early sixth century using historical, ion, and particulate data
- What caused terrestrial dust loading and climate downturns between A.D. 533 and 540?
- The character of the Moho and lower crust within Archean cratons and the tectonic implications
- Exotic Grains in a Core from Cornwall, NY - Do They Have an Impact Source?
- Mega Tsunami of the World Oceans: Chevron Dune Formation, Micro-Ejecta, and Rapid Climate Change as the Evidence of Recent Oceanic Bolide Impacts
- Heat flow from the Southeast Indian Ridge flanks between 80°E and 140°E: Data review and analysis
- Burckle abyssal impact crater: Did this impact produce a global deluge?
- Implications of the Temporal Distribution of High‐Mg Magmas for Mantle Plume Volcanism through Time
- Geologic evidence for a mantle superplume event at 1.9 Ga
- Plume-related mafic volcanism and the deposition of banded iron formation
- Increased mantle convection during the mid-Cretaceous: A comparative study of mantle potential temperature
- Influence of the tectosphere upon plate motion
- The structural and geochemical evolution of the continental crust: Support for the oceanic plateau model of continental growth
- An empirical thermal history of the Earth's upper mantle
- Topographic relief and sediment thickness: Their effects on the thermal evolution of the oceanic crust
- Heat flow constraints on the South Pacific Superswell
- The case for accretion of the tectosphere by buoyant subduction
- Has the Wharton Basin's Heat flow been perturbed by the formation of a diffuse plate boundary in the Indian Ocean?
- A statistical correlation between Ridge Crest offsets and spreading rate
- Heat flow measurements on a hydrothermally-active, slow-spreading ridge: The Escanaba Trough
- Tectonically controlled origin of three unusual rock suites in the Woodlark Basin
- Age of oceanic plates at subduction and volatile recycling
- Archaean plate tectonics revisited 1. Heat flow, spreading rate, and the age of subducting oceanic lithosphere and their effects on the origin and evolution of continents
- Archaean plate tectonics revisited 2. Paleo-sea level changes, continental area, oceanic heat loss and the area-age distribution of the ocean basins
- Correlated sediment thickness, temperature gradient and excess pore pressure in a marine fault block basin
- Anomalous heat flow in the northwest Atlantic: A case for continued hydrothermal circulation in 80-M.Y. crust
- Constraints upon water advection in sediments of the Mariana Trough
- Evidence for excess pore pressures in southwest Indian Ocean sediments