Precambrian
Precambrian A name that is now used only informally to describe the longest period of geological time, which began with the consolidation of the Earth's crust and ended with the beginning of the
Cambrian Period 590 Ma ago. The Precambrian lasted approximately 4000 Ma; the rocks of this period of geological time are usually altered and few fossils with hard parts or skeletons have been found within them, although Precambrian limestone rocks in Australia, Siberia, and parts of the USA contain
stromatolites, which are believed to have been formed by cyanobacteria; frond-like impressions of a supposed plant (Charnia) have also been found. The
Ediacaran fauna is late Precambrian. Precambrian rocks outcrop extensively in shield areas such as northern Canada and the Baltic Sea. In modern usage the Precambrian is subdivided into the
Proterozoic,
Archaean, and
Priscoan.
Cite this article
Pick a style below, and copy the text for your bibliography.
|
Angang's 3200 cubic meter blast furnace begins operation.
Newspaper article from: China Business News; 4/15/2003; 569 words
; ...000 tons of pig iron daily. Furnace productivity can reach 2...years. With the new No. 1 blast furnace in operation, fume exhaust...USD 12.08) per ton. The furnace is able to provide pig iron...Angang previously had ten blast furnaces, with a total effective capacity...
|
 "Post-Tribune (IN)")
|
PUC professor wins blast furnace grant
Newspaper article from: Post-Tribune (IN); 2/19/2003; ; 642 words
; ...to extend the life of blast furnaces at Ispat Inland...transfer in the blast furnaces. In steelmaking, a blast furnace is charged with iron...produce steel. "The blast furnace is the key to...life of a steel mill blast furnace is about 12...extend the life ...
|
|
Mechel Announces Blast Furnace Commissioning at its Chelyabinsk Metallurgical Plant Subsidiary.
PR Newswire Europe; 4/6/2009; 700+ words
; ...companies, announces that blast furnace No. 4 was officially...category capital repair. Blast furnace No. 4 was delayed in November...stayed idle. The renewed furnace will produce about 3,000...the commissioning of blast furnace No. 4, the plant's workshop operated with two ...
|
|
Steelmakers' iron resolve: the search is on for economical alternatives to the stalwart blast furnace. (Newsfront).
Magazine article from: Chemical Engineering; 10/1/2002; ; 700+ words
; ...the traditional blast-furnace process for making...many of the blast furnaces at integrated steelmaking...down both of its blast furnaces, externally...its basic oxygen furnace (BOF) feed. Beginning...alternative to using blast furnaces to produce pig ...
|
|
U. S. Steel Confirms Blast Furnace Incident at U. S. Steel Kosice.
PR Newswire; 1/7/2002; 629 words
; ...exhaust pipe of the No. 3 blast furnace at the company's...incident. Operation of the furnace was immediately halted and the furnace isolated from the gas system...performed in the vicinity of the furnace to ensure the safety of all...Kosice has three operable blast furnaces. ...
|
 "Times (Munster, IN)")
|
Mittal idles East Chicago blast furnace to keep prices firm as demand drops.
Newspaper article from: Times (Munster, IN); 10/6/2006; 700+ words
; ...indefinitely idling one blast furnace at its Indiana Harbor...determined which of the blast furnaces will be idled, company...company said. "The furnaces will be reactivated...USA idled two blast furnaces, one at Indiana Harbor...The Indiana Harbor furnace was idled in ...
|
|
|
East Chicago, Ind., Steelmaker Sells Two Blast Furnaces for Scrap.
Newspaper article from: Times (Munster, IN); 1/15/2004; 700+ words
; ...demolishing two 62-year-old blast furnaces to recover and reuse...operations. The 105-foot-high furnaces at Plant No. 3 each produced...of molten iron daily. The furnaces have played supporting roles...was $93.50. The combined furnaces will create 12,000 tons...for the plant's electric ...
|
|
|
Construction accident could delay completion Gary, Ind., blast furnace.
Newspaper article from: Times (Munster, IN); 9/12/2005; 700+ words
; ...Steel Gary Works No. 14 blast furnace. Nobody was injured...Furnace No. 13. The rebuilt furnace is being renamed No. 14 in...Steel has said. The new furnace's shell is being reassembled...extensive training programs on the furnace's operations. Blast furnaces are where ...
|
|
Blast furnace explodes in Slovakia. (Metal Industry News).(Brief Article)
Magazine article from: Metal Center News; 2/1/2002; 555 words
; ...exhaust pipe of the No. 3 blast furnace at U.S. Steel Kosice...reports. Operation of the furnace was halted and the furnace was isolated from the gas...Kosice has three operable blast furnaces. At this time, the scope...
|
|
Experimental study of phase equilibria in the PbO-ZnO"Fe^sub 2^O^sub 3^"-(CaO + SiO^sub 2^) system in air for the lead and zinc blast furnace sinters (CaO/SiO^sub 2^ weight ratio of 0.933 and PbO/(CaO + SiO^sub 2^) ratios of 2.0 and 3.2)
Magazine article from: Metallurgical and Materials Transactions; 8/1/2003; ; 700+ words
; ...encountered in lead and zinc blast furnace sinters. The liquidus in...certain lead and zinc blast furnace sinters. The oxidation roasting...4] and zinc[5] blast furnaces. The sinter produced in the...MIM) lead sinter/blast furnace operation has historically...
|
|
SIC 3312 Steel Works, Blast Furnaces (Including Coke Ovens), and Rolling Mills
Encyclopedia entry from: Encyclopedia of American Industries
SIC 3312 STEEL WORKS, BLAST FURNACES (INCLUDING COKE OVENS), AND ROLLING MILLS This classification...plates, sheets, strips, rods, bars, and tubing. Merchant blast furnaces and by-product or beehive coke ovens are also included in...
|
|
Blast Furnaces, Early
Dictionary entry from: Dictionary of American History
BLAST FURNACES, EARLY BLAST FURNACES, EARLY. Blast furnaces use fuel to smelt iron ore, often with a flux to facilitate...into final cast products, more typically early blast furnace molten ore was cooled into ingots or "pigs." Foundries...
|
|
blast furnace
Book article from: The Columbia Encyclopedia, Sixth Edition
blast furnace structure used chiefly in smelting...oxide in order to obtain the metal. Blast furnaces differ in construction. The one used...fine molten products are caught. The furnace is fed from the top with a charge of...
|
|
|
SIC 3567 Industrial Process Furnaces and Ovens
Encyclopedia entry from: Encyclopedia of American Industries
...performance of the Bessemer furnace by using oxygen instead of air and the Bessemer furnace once again took the lead...using the Bessemer oxygen furnace for 59.7 percent of production...5 percent, and electric furnaces had grabbed 36.8 percent...close outdated smelters and blast ...
|
|
|
furnace
Book article from: The Columbia Encyclopedia, Sixth Edition
...common. The kiln is a kind of furnace. In metallurgy, the separation...by the use of various kinds of furnaces, e.g., the blast furnace and the reverberatory furnace. The structure of these furnaces makes possible a good control...
|
