Publications
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Holocene Treeline Fluctuations in the Northern San Juan Mountains, Colorado, U.S.A., as Indicated by Radiocarbon-Dated Conifer Wood
An early to mid-Holocene warm period with greater than present-day monsoonal circulation is indicated by evidence in the northern San Juan Mountains of southwestern Colorado. Fifty radiocarbon ages of coniferous wood fragments, and several other radiocarbon ages of willow fragments, woody peat, and organic sediment associated with conifer remains, recovered from six sites at or above present-day t
Authors
Paul E. Carrara, Deborah A. Trimble, Meyer Rubin
U-Th-Pb Isotopic Systematics of Lunar Norite 78235
No abstract available.
Authors
Wayne R. Premo, M. Tatsumoto
U-Pb isotopic characteristics of lunar meteorites Yamato-793274 and Yamato-86032
No abstract available.
Authors
Mistunobu Tatsumoto, Wayne R. Premo
Quaternary history of some southern and central Rocky Mountain basins
This chapter summarizes the current state of late Cenozoic stratigraphic knowledge in some Rocky Mountain basins (here defined as the structurally low portions of major drainage basins) that have been studied in detail since Scott’s (1965) summary on the nonglacial history of the southern and middle Rocky Mountains. The Quaternary history of few of these basins has been studied as intensively as t
Authors
Marith C. Reheis, Robert C. Palmquist, S.S. Agard, Cheryl Jaworowski, Brainerd Mears, Richard F. Madole, Alan R. Nelson, Gerald Osborn
Assessing the natural performance of felsic tuffs using the Rb-Sr and Sm-Nd systems-A study of the altered zone in the Topopah Spring Member, Paintbrush Tuff, Yucca Mountain, Nevada
Core samples of the Topopah Spring Member of the Paintbrush Tuff from drill hole UE25A#1 were analyzed for Sr and Nd isotopes and selected minor and trace elements to constrain the origin of a zcolitized zone associated with the lower vitrophyre. The Sm-Nd radiogenic isotope system was unperturbed by the alteration, but the Rb-Sr system was severely disturbed in the altered zone. The thick, densel
Authors
Zell E. Peterman, Richard W. Spengler, Kiyoto Futa, Brian D. Marshall
Age estimates and uplift rates for late Pleistocene marine terraces: Southern Oregon portion of the Cascadia forearc
Interest in the Cascadia subduction zone has increased because recent investigations have suggested that slip along plates at certain types of convergent margins is characteristically accompanied by large earthquakes. In addition, other investigations have suggested that convergent margins can be broadly classified by the magnitude of their uplift rates. The authors generated new uranium series, a
Authors
Daniel R. Muhs, Harvey M. Kelsey, Joseph F. Whelan, Galan W. McInelly
Iron sulfide minerals at Cement oil field, Oklahoma: Implications for magnetic detection of oil fields
Aeromagnetic anomalies at Cement oil field (Anadarko basin, Oklahoma) have been attributed to authigenic magnetite. The following characteristics of the magnetite, however, indicate that it is contamination introduced by drilling: (1) occurrence as sharp angular blades and as spheres, commonly with metallographic textures typical of industrial alloys and with associated steel and wustite (FeO); (2
Authors
Richard L. Reynolds, Neil S. Fishman, Richard B. Wanty, Martin B. Goldhaber
Saline minerals in the Lewis Cliff ice tongue, Buckley Island Quadrangle, Antarctica
No abstract available.
Authors
J. J. Fitzpatrick, D.R. Muhs, A.J.T. Jull
Influence of climate and eolian dust on the major-element chemistry and clay mineralogy of soils in the northern Bighorn basin, U.S.A.
Soil chronosequences in the northern Bighorn basin permit the study of chronologic changes in the major-element chemistry and clay mineralogy of soils formed in different climates. Two chronosequences along Rock Creek in south-central Montana formed on granitic alluvium in humid and semiarid climates over the past two million years. A chronosequence at the Kane fans in north-central Wyoming formed
Authors
Marith C. Reheis