rock
rock A consolidated or unconsolidated aggregate of
minerals or organic matter. The minerals may be all of one type, in which case the rock is ‘monomineralic’, or of many types, in which case it is ‘polymineralic’. The aggregate of minerals can form by: (
a) accretion or precipitation of grains during Earth surface processes, to give
sedimentary rocks; (
b) crystallization of
magma to give
igneous rocks; and (
c) solid-state
recrystallization in response to changes in external conditions (e.g. pressure and temperature) to give
metamorphic rocks. The grain relationships (
textures) of these three rock types contrast. Sedimentary rocks are characterized by one of the following: (i) rounded or angular grains held together by an intergrain precipitate or a fine intergrain mud; (ii) fine aggregates of
clay minerals displaying a preferred orientation of their long axes; (iii) a crystalline aggregate of minerals (e.g.
calcite) displaying straight edges and triple junctions between the grains; (iv) an aggregate of
fossil fragments held together by an interfragment precipitate of
calcite or a fine interfragment mud; or (v) an aggregate of organic material (e.g.
lignite or
coal). All igneous rocks are characterized by an aggregate of minerals displaying an interlocking texture. Metamorphic rocks are characterized by one of the following: (i) a crystalline aggregate of minerals which display a preferred orientation of their long axes; (ii) a crystalline aggregate of equidimensional and randomly oriented non-equidimensional minerals; or (iii) an extremely fine-grained aggregate of sutured,
anhedral, or sometimes elongate minerals.
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Roosevelt Institute Names New Center For Henry A. Wallace
Newspaper article from: U.S. Newswire; 1/9/2001; 608 words
; ...Roosevelt Presidential Library will be named for Henry Agard Wallace, FDR's dynamic Secretary of Agriculture during...FERI Chairman, Ambassador William vanden Heuvel. "Henry Wallace stands as one of the most innovative and forward...
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AMERICAN DREAMER: A Life of Henry A. Wallace.(Review)
Magazine article from: Washington Monthly; 5/1/2000; ; 700+ words
; ...AMERICAN DREAMER: A Life of Henry A. Wallace By John C. Culver and John Hyde...the calm of long-ago history (Wallace died nearly 35 years ago) about...s twentieth century. Who was Henry Agard Wallace? Son of a Republican secretary...
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Bountiful Harvest
Newspaper article from: The Washington Post; 6/18/2000; ; 700+ words
; AMERICAN DREAMER The Life and Times of Henry A. Wallace By John C. Culver and John Hyde Norton. 608 pp...American Dreamer is the first full biography of Henry Agard Wallace, just maybe the most fascinating and certainly...
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The evil eye: the occult symbol chosen for the Orwellian Information Awareness Office has links to ancient paganism and modern revolutionary Communism. (Cover Story: On the Home Front).(Cover Story)
Magazine article from: The New American; 1/27/2003; ; 700+ words
; ...currency by way of a very odd and subversive man, Henry Agard Wallace, who served in two of our nation's top political...pyramid with the all-seeing eye on U.S. currency. Henry Wallace's fascination with the occult is mentioned in Arthur...
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Development of the American Economy.(Program and Working Group Meetings)
Magazine article from: NBER Reporter; 1/1/2007; 700+ words
; ...University of California, Riverside, and NBER, "Henry Agard Wallace, the Iowa Corn Tests, and the Adoption of Hybrid...at the direction of the Secretary of Agriculture, Henry Agard Wallace. The Department's campaign echoed that of the...
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Conservative forum
Magazine article from: Human Events; 2/3/2003; ; 700+ words
; ...war? -Walter W. Palmer Chino Valley, Ariz. On Henry A. Wallace As Radical Socialist It figures that the Clinton...Agriculture Department to its leftist former secretary, Henry Agard Wallace, who also served as Vice President under Franklin...
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Peace for sale? // Naw, just a campaign collectible
Newspaper article from: Chicago Sun-Times; 10/19/1988; 700+ words
; ...world peace on or after Nov. 2, 1948." Photos of Henry A. Wallace and Glen H. Taylor are on the paper. What exactly...be valuable? ALL EARS, Stickney Dear All Ears: Henry Agard Wallace was vice president under Franklin D. Roosevelt...
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IOWA'S STORY IS AMERICA'S
Newspaper article from: The Boston Globe; 1/24/2000; ; 700+ words
; ...in obscure Adair County, is the birthplace of Henry Agard Wallace. Wallace - publisher, philosopher, politician - stood firmly...presidential campaign on the Progressive ticket, Wallace personified the transformation from local to national...
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Vilsack has a lot on his plate as U.S. agriculture secretary
Newspaper article from: Telegraph - Herald (Dubuque); 1/25/2009; ; 700+ words
; ...to do so under three presidents. Another notable Iowan to fill the Cabinet seat was Henry Agard Wallace, from 1933 to 40. His father, Henry Cantwell Wallace, served in the position from 1921 to 24, and Junior became famous for his invention...
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Climate Change: Past and Present.(Conferences)
Magazine article from: NBER Reporter; 6/22/2008; 700+ words
; ...Historical Experience in the Western United States" Richard Sutch, University of California, Riverside and NBER, "Henry Agard Wallace, the Iowa Corn Yield Tests, and the Adoption of Hybrid Corn: American Corn Yields, 1866-2002" Raghav Gaiha...
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Henry Agard Wallace
Encyclopedia entry from: Encyclopedia of World Biography
Henry Agard Wallace Henry Agard Wallace (1888-1965), a secretary of agriculture and of commerce and vice president of the United States, was one of the most controversial Federal officials for 13 years. Wallace became almost the official...
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Wallace, Henry Agard
Book article from: World Encyclopedia
Wallace, Henry Agard (1888–1965) US staesman, vice president (1941–45). As vice president under Franklin D. Roosevelt...
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Henry Cantwell Wallace
Book article from: The Columbia Encyclopedia, Sixth Edition
...Ill., grad. Iowa State College of Agriculture (now Iowa State Univ.), 1892; son of Henry Wallace (1836-1916) and father of Henry Agard Wallace . Harry Wallace, as he often was called, was associated with his father in founding Wallaces...
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Pioneer Hi-Bred International, Inc.
Book article from: International Directory of Company Histories
...Company under the leadership of Henry Agard Wallace. Before the company was created...forward-looking people was young Henry A. Wallace. At 16, he conducted...weren ’ t published. But Henry Wallace had an advantage over many researchers...
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