Variations of Blue, Hoh, and White Glaciers During Recent Centuries

Glaciers in the Olympic Mountains of western Washington, as elsewhere in North America, enlarged in late-postglacial time and attained positions from which they have receded conspicuously. Former locations of the ice are marked by moraines and overridden surfaces which the regional vegetation is slowly invading. An examination of aerial photographs of glaciers on Mt. Olympus taken in 1939 and 1952 clearly reveals the progress of recession. In 1952 Blue and Hoh glaciers appear rather inactive whereas a photograph of Blue Glacier taken about the turn of the century shows an actively discharging tongue, well in advance of its position in the early 1950's. About 1900 glacier termini were nevertheless well behind positions reached when the ice stood farther down the valleys in past centuries. No written accounts or measurements are available from this pre-1900 period, although the ages of trees growing on moraines and outwash offer the means for fixing positions of the glaciers during the time before the earliest observations. The minimum periods elapsed since glaciers may have been even farther advanced are established by the ages of the oldest trees in the forests beyond the recent outermost limits of the ice. A reconnaissance of Blue and Hoh glaciers and the vicinity of White Glacier was made during the 1955 summer, and the former limits of the ice were determined and dated. The purpose was to record the variations of Mt. Olympus glaciers so that the climate of this region during the last several centuries might be interpreted from these changes and compared with other localities where similar studies have been made. ..

Radiocarbon Dates of Peats from North Pacific North America

Ages are presented for 17 late-Pleistocene peat samples from sectios that range from Karluck on Kodiak Island, Alaska to Port Orford, Oregon. Pollen and peat stratigraphy of the sections is used to interpret the environments prevailing at and since the time of sample deposition. The late-glacial at more southerly Pacific coastal Alaskan sites is dated at ca. 10,800 B.P. and the postglacial at ca. 10,000 B.P. At northerly coastal sites these intervals begin somewhat later. Regression rates for sealevel are given for a number of sites along this coast. Sample ages from two Oregon lakes suggest eustatic transgression ca. 5000 B.P. during the Hypsithermal interval.This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

History of an estuarine bog at Secaucus, New Jersey

Taken from the Bulletin of the Torrey Botanical Club, Nov. 1949 ; a botanical survey of the Hackensack River Estuar

Cueva del Medio: A Paleoindian Site and Its Environmental Setting in Southern South America

This article reports the results of the palynological analysis obtained from one of the archaeological profiles exposed at Cueva del Medio, a Paleoindian site located at the southern tip of South America (Ultima Esperanza, Chile). The earliest occupation is located over a sand layer which follows the natural slope of the sedimentological matrix of the cave. The findings of this level are significant,as they demonstrate a clear Paleoindian context, linking humans with extinct fauna. Based on the palynological analysis and previous results obtained in the region, the environmental setting of Cueva del Medio is described. Paleoindian occupations of the cave, estimated to date from approximately 11 - 10 kya, may have taken place at about the time of initial, albeit ephemeral, Nothofagus expansion. Climate becoming more mesic was evidently transitory, and possibly favored some development of arboreal communities. Summer drought for a time afterward, in turn, was less favorable to the spread of trees, as inferred by the successive prevalence of steppe.Fil: Nami, Hugo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Heusser, Calvin J.. No especifica

Troncos de Salix Humboldtiana en depósitos aluviales del Holoceno tardío, río Sauce Grande (Provincia de Buenos Aires)

El presente trabajo tiene como objetivo la presentación de este hallazgo, discutir la estratigrafía y la cronología de los sedimentos portadores e intentar la reconstrucción de las características paleoambientales. Para ello, fueron realizados perfiles estratigráficos en las localidades estudiadas, muestreo de las unidades reconocidas, estudio palinológico en doce niveles distintos, muestreo de materiales orgánicos para fechado radiocarbónico y recolección de troncos para su estudio xilològico