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K. M. Reed

Publications and source records attributed to K. M. Reed.

8 recordsLinked to original sources
USGS2017

Late Pleistocene Vertebrates and Other Fossils from Epiguruk, Northwestern Alaska

Sediments exposed at Epiguruk, a large cutbank on the Kobuk River about 170 km inland from Kotzebue Sound, record multiple episodes of glacial-age alluviation followed by interstadial downcutting and formation of paleosols. Vertebrate remains from Epiguruk include mammoth, bison, caribou, an equid, a canid, arctic ground squirrel, lemmings, and voles. Radiocarbon ages of bone validated by concordant ages of peat and wood span the interval between about 37,000 and 14,000 yr B.P. The late Pleistocene pollen record is dominated by Cyperaceae, with Artemisia, Salix, Betula, and Gramineae also generally abundant. The fossil record from Epiguruk indicates that the Kobuk River valley supported tundra vegetation with abundant riparian willows during middle and late Wisconsin time. Large herbivores were present during the height of late Wisconsin glaciation as well as during its waning stage and the preceding interstadial interval. The Kobuk River valley would have been a favorable refugium for plants, animals, and possibly humans throughout the last glaciation.

Quaternary Research↗
USGS1995

Radiolarian biostratigraphy of the Quinn River Formation, Black Rock terrane, north-central Nevada: correlations with eastern Klamath terrane geology

The Quinn River Formation, Black Rock terrane, Quinn River Crossing, is one of the few Nevadan sections of Permian and Triassic strata that are unaffected by Sonoman deformation. The formation consists of: 1) a basal tuff overlain by limestone and ferruginous dolomite, 2) interbedded radiolarian-bearing chert and argillite, 3) siltstone and carbonaceous shale, and 4) partly volcaniclastic rocks. All but the uppermost (barren) chert samples contain Late Permian radiolarian taxa. These radiolarians suggest that early Wordian conodonts reported from near the top of the chert and argillite unit are reworked. Poorly preserved Early(?) or Middle triassic radiolarians and Middle Triassic ammonites and pectenacid bivalves from the middle part of the volcaniclastic unit indicate the Early Triassic deposition cannot be documented at Quinn River. The ages of the Quinn River brachiopod, conodont, and radiolarian faunas resemble those of the Dekkas and Pit Formations, eastern Klamath terrane, northern California. The analogous Quinn River and eastern Klamath rock types and faunal ages, as well as similar hiatuses in their stratigraphic records, suggest that they may be lateral equivalents that formed in the same island-arc sedimentary basin. -from Authors

Micropaleontology↗
USGS1993

Acid processing of pre-Tertiary radiolarian cherts and its impact on faunal content and biozonal correlation

The numbers of radiolarians visible in thin sections of chert-rich rocks are commonly an order of magnitude greater than the numbers observed on the surfaces of fragments etched by hydrofluoric acid (HF) and typically orders of magnitude greater than the numbers of individuals found in HF-processed residues. Destruction of radiolarians during both diagenesis and HF processing severely reduces faunal abundance and diversity and affects the taxonomic and biostratigraphic utility of chert residues. The robust forms that survive the processing represent only a small fraction of the death assemblage, and delicate skeletal structures used for species differentiation, commonly preserved in limestone radiolarian faunas, are either poorly preserved or dissolved in many coeval chert residues. First and last occurrences of taxa in chert sequences are likely to be coarse approximations of their true stratigraphic ranges. Precise correlation is difficult between biozonations based solely on index species from cherts and those constructed from limestone faunas. Careful selection of samples in sequence, use of weaker HF solutions, and study of both chert and limestone faunas should yield better biostratigraphic information.

Geology↗
USGS1992

Permian and early(?) Triassic radiolarian faunas from the Grindstone Terrane, central Oregon

Moderately well preserved Permian and Early(?) Triassic radiolarian faunas from sedimentary melange cherts of the Grindstone terrane in central Oregon are nearly identical to coeval chert faunas in Japan. Although several Oregon taxa have been reported from limestone sequences in the central United States, most of the Oregon forms have only been found in cherty rocks and nearly half have not previously been reported from North America. Forty-two taxa belonging to 19 genera are systematically treated. Co-occurrences of some species in Oregon indicate that their ranges in North America may differ from those in Japan. -from Authors

Journal of Paleontology↗
USGS1976

Geohydrology and water supply, Shemya Island, Alaska

Sheyma Island, Alaska, was occupied as a military base in 1942. Since that time, potable water has been supplied by streams, lakes, wells, and in the late 1950's, a gallery system. The island is a low-lying, wave-cut platform composed of pyroclastic and volcanic rocks with some intrusives. Bedrock is overlain by thin glacial deposits. Most of the island 's present surface is relatively thick peat deposits. On the southern and western sides of the island active sand dunes are present. Ground-water supplies are limited by the dense bedrock; only a small amount of water penetrates into fracture systems. Most ground-water movement is in the overlying glacial and peat deposits. Ground water moves generally from north to south across the island. Currently water supplies are drawn from the gallery system which is capable of providing about 200,000 gallons per day. An emergency water supply is available from two wells. Additional supplies could be developed by either adding to the existing gallery or constructing an additional gallery near the present gallery system. The chemical quality of water analyzed from the gallery well generally approximates that of surface water on the island. None of the constituents in samples from streams, lakes, or ground water, except the August 27, 1970, analysis for Lower Lake, exceed the recommended limits for drinking water (Environmental Protection Agency, 1973).

Alaska↗