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Richard M. O’Leary

Publications and source records attributed to Richard M. O’Leary.

10 recordsLinked to original sources
USGS2010

Stream-sediment samples reanalyzed for major, rare earth, and trace elements from seven 1:250,000-scale quadrangles, south-central Alaska, 2007-09

During the 1960s through the 1980s, the U.S. Geological Survey conducted reconnaissance geochemical surveys of drainage basins throughout most of the Iliamna, Lake Clark, Lime Hills, and Talkeetna 1:250,000-scale quadrangles and parts of the McGrath, Seldovia, and Tyonek 1:250,000-scale quadrangles in Alaska. These geochemical surveys provide data necessary to assess the potential for undiscovered mineral resources and provide data that may be used to determine regional-scale element baselines. This report provides new data for 1,075 of the previously collected stream-sediment samples. The new analyses include a broader spectrum of elements and provide data that are more precise than the original analyses. All samples were analyzed for arsenic by hydride generation atomic absorption spectrometry, for gold, palladium, and platinum by inductively coupled plasma-mass spectrometry after lead button fire assay separation, and for a suite of 55 major, rare earth, and trace elements by inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry after sodium peroxide sinter at 450 degrees Celsius.

Data Series↗
USGS2010

Stream-sediment samples reanalyzed for major, rare earth, and trace elements from ten 1:250,000-scale quadrangles, south-central Alaska, 2007-08

During the 1960s through the 1980s, the U.S. Geological Survey (USGS) conducted reconnaissance geochemical surveys of the drainage basins throughout most of the Anchorage, Bering Glacier, Big Delta, Gulkana, Healy, McCarthy, Mount Hayes, Nabesna, Talkeetna Mountains, and Valdez 1:250,000-scale quadrangles in Alaska as part of the Alaska Mineral Resource Assessment Program (AMRAP). These geochemical surveys provide data necessary to assess the potential for undiscovered mineral resources on public and other lands, and provide data that may be used to determine regional-scale element baselines. This report provides new data for 366 of the previously collected stream-sediment samples. These samples were selected for reanalysis because recently developed analytical methods can detect additional elements of interest and have lower detection limits than the methods used when these samples were originally analyzed. These samples were all analyzed for arsenic by hydride generation atomic absorption spectrometry (HGAAS), for gold, palladium, and platinum by inductively coupled plasma-mass spectrometry after lead button fire assay separation (FA/ICP-MS), and for a suite of 55 major, rare earth, and trace elements by inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry (ICP-AES-MS) after sodium peroxide sinter at 450 degrees Celsius.

Open-File Report↗
USGS1987

Tables showing analyses of semiquantitative spectrometry and atomic-absorption spectrophotometry of rock samples collected in the Ugashik, Bristol Bay, and western part of the Karluk quadrangles, Alaska

The accompanying tables list chemical analyses of 337 rock samples that were collected in 1979, 1980, and 1981 in conjunction with geologic mapping in the Ugashik, Bristol Bay, and part of Karluk quadrangles. This work was conducted under the auspices of the Alaska Mineral Resource Assessment Program (AMRAP). This report is to accompany Wilson and O'Leary (1986) which inadvertently is missing most of the data tables listed here. Together the two reports contain the complete data from all samples collected for the Ugashik AMRAP.

Alaska↗
USGS1976

Spectrographic and chemical analyses of geochemical samples from the McCarthy Quadrangle, Alaska

As an integral part of the Alaskan Mineral Resource Assessment Program, a geochemical reconnaissance survey was conducted in the McCarthy quadrangle during the summer of 1974. The investigation consisted of geochemical sampling, multielement chemical and spectrographic analyses, compilation of new and existing geochemical data, statistical evaluation of the total data set, and the generation of element distribution and abundance maps. The purpose of the survey was to define areas in the quadrangle that contain anomalous concentrations of metallic and nonmetallic elements. These studies are fundamental to a comprehensive evaluation of the mineral resource potential of the area and to assist in the discovery of additional economic mineral deposits. The first-large scale geochemical sampling and analytical surveys were initiated in the McCarthy quadrangle in the early 1960's with the inception of the Wrangell Mountain project by the U.S. Geological Survey. Since that time, levels of activity in geochemical sampling in the quadrangle have fluctuated. Each year, many geochemical samples have been collected concomitantly with geologic mapping, and was culminated under the Alaskan Minerals Resource Assessment Program 1974.

Alaska↗