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M. Miller

Publications and source records attributed to M. Miller.

At least 19 recordsLinked to original sources
USGS2014

Investigation of the high-frequency attenuation parameter, κ (kappa), from aftershocks of the 2010 M w 8.8 Maule, Chile earthquake

The Bío Bío region of Chile experienced a vigorous aftershock sequence following the 2010 February 27 M w 8.8 Maule earthquake. The immediate aftershock sequence was captured by two temporary seismic deployments: the Quake Catcher Network Rapid Aftershock Mobilization Program (QCN RAMP) and the Incorporated Research Institutions for Seismology CHile Aftershock Mobilization Program (IRIS CHAMP). Here, we use moderate to large aftershocks ( M L ≥ 4.0) occurring between 2010 March 1 and June 30 recorded by QCN RAMP and IRIS CHAMP stations to determine the spectral decay parameter, kappa ( κ ). First, we compare waveforms and κ estimates from the lower-resolution QCN stations to the IRIS CHAMP stations to ensure the QCN data are of sufficient quality. We find that QCN stations provide reasonable estimates of κ in comparison to traditional seismic sensors and provide valuable additional observations of local ground motion variation. Using data from both deployments, we investigate the variation in κ for the region to determine if κ is influenced primarily by local geological structure, path attenuation, or source properties (e.g. magnitude, mechanism and depth). Estimates of κ for the Bío Bío region range from 0.0022 to 0.0704 s with a mean of 0.0295 s and are in good agreement with κ values previously reported for similar tectonic environments. κ correlates with epicentral distance and, to a lesser degree, with source magnitude. We find little to no correlation between the site kappa, κ 0 , and mapped geology, although we were only able to compare the data to a low-resolution map of surficial geology. These results support an increasing number of studies that suggest κ observations can be attributed to a combination of source, path and site properties; additionally, measured κ are often highly scattered making it difficult to separate the contribution from each of these factors. Thus, our results suggest that contributions from the site, path and source should be carefully considered when interpreting κ values.

Bío Bío Region↗
USGS2013

Barite

Barite is the mineralogical name for barium sulfate, which is also referred to as barytes. The most basic marketable product is known as “crude barite,” which is barite that usually has undergone simple beneficiation methods, such as jigging, tabling and washing, or more complex methods, such as flotation, heavy-media separation and magnetic separation. Most barite ore requires some upgrading to minimum purity or density levels.

Mining Engineering↗
USGS2013

Fluorspar

World fluorspar demand slowed in 2012 and, according to some sources prices decreased, especially in the latter half of the year. In 2012, nearly all fluorspar (CaF 2 ) consumption in the United States was from imports. Hastie Mining and Trucking Co. produced some fluorspar as a byproduct of its limestone quarry operations in Illinois. In addition, a small amount of usable synthetic fluorspar was produced from industrial waste streams.

Mining Engineering↗
USGS2012

Fluorspar

World fluorspar demand continued to show signs of recovery from 2008-2009 recession. In 2011, nearly all fluorspar (CaF 2 ) consumed in the United States was imported. Hastie Mining and Trucking Co. produced some fluorspar as a byproduct from its limestone quarry operations in Illinois. In addition, a small amount of usable synthetic fluorspar was produced from industrial waste streams.

Mining Engineering↗
USGS2011

Barite

The article discusses the latest developments in the barite or baryte industry, particularly in the U.S., as of June 2011. It claims that the bulk of barites production in the country comes from four mines in Nevada, including the Big Ledge Mine, the Rossi Mine and the Greystone Mine. It cites that barite is mainly used as a weighting agent in natural gas and oil field drilling muds. Barite is also utilized as filler, extender or weighting agent in such products as paints, plastics and rubber.

Mining Engineering↗
USGS2010

Fluorspar

Statistics on fluorspar consumption, prices, and trade in 2009 are presented. Information on the mine developments and closures and on the outlook for the sector is provided.

Mining Engineering↗
USGS2007

Fluorspar

Apart from some fluorspar by-product, there was no U.S. production of fluorspar in 2006. Imports were 553 kt, nearly 14 percent less than in 2005, and China was by far the largest supplier. China's changing export policy and high ocean freight rates indicate that delivered prices for fluorspar may increase in 2007 and countries such as Mexico, Mongolia, and South Africa are gaining market share.

Mining Engineering↗
USGS2004

Zoonotic protozoa in the marine environment: a threat to aquatic mammals and public health

This collection of abstracts provides an account of four presentations at the 19th International Conference of the World Association for the Advancement of Veterinary Parasitology (WAAVP) (held in New Orleans, LA, USA from 10–14 August 2003) in a symposium session on zoonotic protozoan parasites found in the marine environment and chaired by Ronald Fayer and David Lindsay. The focus was on three genera of parasites of veterinary and public health concern - Toxoplasma , Giardia , and Cryptosporidium with emphasis on their epidemiology in the marine environment.

Veterinary Parasitology↗
USGS2004

Fluorspar

Supply and demand data for fluorspar are provided. Industry developments and the outlook for 2005 are discussed.

Mining Engineering↗
USGS2003

Fluorspar

The United States had a small quantity of fluorspar production from one mine in Utah during 2002. Most of the fluorspar consumed in the United States continued to come from imports or material purchased from the National Defense Stockpile (NDS). In addition, a small amount of synthetic fluorspar (CaF 2 ) was produced from industrial waste streams.

Mining Engineering↗
USGS2002

Fluorspar

In 2001, one mine in Utah produced a small quantity of fluorspar. The majority of fluorspar consumed in the United States continued to come from imports or material purchased from the US National Defense Stockpile (NDS). In addition, a small amount of synthetic fluorspar (CaF 2 ) was produced from industrial waste streams.

Mining Engineering↗
USGS2001

Fluorspar

A general overview of the fluorspar industry is provided. The U.S. had no reported mine production in 2000. Imports, sales from the U.S. National Defense Stockpile, and small amounts of synthetic fluorspar met domestic fluorspar needs. According to the U.S. Geographical Survey, 509 kt of fluorspar was consumed domestically.

Mining Engineering↗
USGS1998

Fluorspar

The state of the fluorspar industry worldwide for 1997 is discussed. The U.S. had no reported mining of fluorspar in 1997. Reported consumption in the U.S. decreased to 490 kt. U.S. imports, mainly from China, totaled 533 kt. Exports, synthetic fluorspar production, and industry developments are also reviewed.

Mining Engineering↗
USGS1997

Fluorspar

Developments in the area of fluorspar in 1996 are reviewed. There was no reported mine production of fluorspar the U.S. in 1996, so domestic fluorspar requirements were satisfied by imports, sales from the National Defense Stockpile, and small amounts of synthetic fluorspar produced from industrial waste. The Defence Logistics Agency, consumption, imports, exports, markets, production of synthetic equivalents, and the lack of major developments in the North American industry are discussed.

Mining Engineering↗
USGS1996

Fluorspar

The U.S. consumed about 525 kt of fluorspar in 1995, with more than 70 percent being used for the production of hydrofluoric acid. Fluorspar is also used for the production of aluminum and steel. About 558 kt of fluorspar was imported in 1995, with a further 186 kt made available from the National Defense Stockpile. The market in the U.S. is expected to grow as increasing use is made of fluorocarbons to replace chlorofluorocarbons.

Mining Engineering↗
USGS1995

Fluorspar

The production, consumption, and applications of fluorspar are reviewed. In 1994, the U.S. exported about 45 kt of fluorspar, but, according to the U.S. Bureau of the Census, 493 kt were imported during the same period. Consumption, according to preliminary figures from the U.S. Bureau of Mines, was about 473 kt. China continued to be the main supplier of imports to the U.S. with 61 percent of the total imports. Of the 3 major fluorspar markets, hydrofluoric acid (HF), aluminum, and steel, the HF market was the only one to record an increase in consumption in 1994.

Mining Engineering↗