Physical Sciences and Mathematics Commons^™

Explorations, Vol. 1, No. 2, Jim I. Mead, Emilee M. Mead, Carol J. Bombard, Ronald B. Davis, Marcella H. Sorg

Explorations — A Journal of Research

The cover print is a multi-plate colored etching entitled Skull and Sun Dial, by Susan Groce, Associate Professor of Art at the University of Maine at Orono, where she teaches Printmaking and Drawing.

Articles include:

"The Quaternary"

"Ice Age Plants and Animals: Secrets of the Colorado Plateau," by Jim I. Mead and Emilee M. Mead

"Finding the Facts: Pieces of the Puzzle"

"On Location: In Search of the First Americans"

"A Temporal Vegetational Continuum: From Tundra to Forest," by Carole J. Bombard for Ronald B. Davis

"Anatomy of an Excavation," by Robson Bonnichsen

"What the Bones Tell Us," by …

Thermal Convection In Ice Sheets: We Look But Do Not See, Terence J. Hughes

Earth Science Faculty Scholarship

Thermal convection in the Antarctic and Greenland ice sheets has been dismissed on the grounds that radio-echo stratigraphy is undisturbed for long distances. However, the undisturbed stratigraphy lies, for the most part, above the density inversion in polar ice sheets and therefore does not disprove convection. An echo-free zone is widespread below the density inversion, yet nobody has cited this as a strong indication that convection is indeed present at d�pth. A generalized Rayleigh criterion for thermal convection in e1astic-viscoplastic polycrystalline solids heated from below is developed and applied to ice-sheet convection. An infinite Rayleigh number at the onset of …

Examination Of Selected Microparticles From The Sentik Glacier Core, Ladakh, Himalayas, Emily Goss, Paul Andrew Mayewski, William Berry Lyons

Earth Science Faculty Scholarship

Several characteristics and interpretive comments are reported for microparticles from selected samples in the Sentik Glacier core. Four basic morphologic groups are defined: Platy, angular, biogenic, and anomalous.

The Glaciochemistry Of Snowpits From Quelccaya Ice Cap, Peru, 1982, W. Berry Lyons, Paul Andrew Mayewski, Lonnie G. Thompson, Boyd Allen Iii

Earth Science Faculty Scholarship

We present glaciochemical data from a pilot study of two snow-pits from Quelccaya ice cap, Peruvian Andes. These are the first samples to be analyzed from Quelccaya for nitrate and sulfate by ion chromatography (IC), for nitrate-plus-nitrite, reactive silicate and reactive iron by colorimetry, and for sodium by atomic absorption spectrophotometry. The 3 m pits used in this study represent a one year record of mass accumulation and the 29 samples collected provide the first glaciochemical data from this area which can be compared with glaciochemical studies from other locations.

Reactive iron, reactive silicate and sodium, and the profiles of …

Glaciochemical Studies And Estimated Net Mass Balances For Rennick Glacier Area, Antarctica, Boyd Allen Iii, Paul Andrew Mayewski, W. Berry Lyons, Mary Jo Spencer

Earth Science Faculty Scholarship

Two snow and ice cores from the Rennick Glacier area, Antarctica (study area center point lat 71° 15' S, long 162° 30' E) were analyzed for the chemical species: chloride, sodium, reactive silicate, sulfate and nitrate. Core E1O (6.35 m) was taken from Evans Névé, a large accumulation basin at the head of Rennick Glacier. Core M1 (4.35 m) was extracted from the accumulation zone on the central plateau of the Morozumi Range, a small mountain massif bordering Rennick Glacier. Cores E1O and M1 span the time periods from 1929 to 1981 and from 1971 to 1981, respectively, as dated …

A Preliminary Assessment Of The Potential Application Of Glaciochemical Investigations On Heard Island, South Indian Ocean, Mary Jo Spencer, Paul Andrew Mayewski, William Berry Lyons, Martin R. Hendy

Earth Science Faculty Scholarship

Analyses of fluoride, chloride, sodium, sulfate, bromide. nitrate, and iron from a 3 m snow pit on Heard Island, collected at an elevation of 2450, m are used to assess the potential of glaciochemical studies on Heard Island glaciers. Sources Cor the chemical species are identified and, in particular, chloride, sodium, and sulCate are found to be useful seasonal indication. The total record measured is believed to be less than one mass-balance year.

Using An Ice Core To Characterize The Climatic History Of Antarctica, Paul Andrew Mayewski, W. B. Lyons

Earth Science Faculty Scholarship

Between 20 November and 14 December 1984, a remote tent camp was operated in the Dominion Range (center point, 85° 15' S 166° 10 'E) on an ice-covered massif located at the confluence of the heads of the Beardmore and Mill Glaciers in the Transantarctic Mountains. The camp was occupied by four members of the Glacier Research Group (University of New Hampshire) and three members of the Polar lee Coring Office (PICO) (University of Nebraska). The main task at the site was to retrieve an ice core from which chemical and physical time series will be made available to help …