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The United States Lake Survey ( USLS) was a hydrographic survey for the Great Lakes, New York Barge Canal, Lake Champlain and the Boundary Waters of the Canada–United States border between Minnesota and Ontario. The Survey's activities began on 31 March 1841, with the goal of surveying the Great Lakes. The Lake Survey was created within the ...
美國地質調查局（英語： United States Geological Survey ，縮寫：USGS），或称美国地质勘探局，是美國內政部轄下的科學機構，是內政部唯一純粹的科學部門，有約一萬名人員，總部設在弗吉尼亚州 里斯頓，在科羅拉多州 丹佛和加利福尼亚州 门洛帕克設有辦事處。
Iron mining in the United States produced 48 million metric tons of iron ore in 2019. [1] Iron ore was the third-highest-value metal mined in the United States, after gold and copper. [2] Iron ore was mined from nine active mines and three reclamation operations in Michigan, Minnesota, and Utah. Most of the iron ore was mined in northern ...
Hydrologic unit system (United States) For the use of hydrologists, ecologists, and water-resource managers in the study of surface water flows in the United States, the United States Geological Survey created a hierarchical system of hydrologic units. Originally a four-tier system divided into regions, sub-regions, accounting units, and ...
US annual gold production (1840–2012) In the United States, gold mining has taken place continually since the discovery of gold at the Reed farm in North Carolina in 1799. The first documented occurrence of gold was in Virginia in 1782. [1] Some minor gold production took place in North Carolina as early as 1793, but created no excitement.
In 1996, shale gas wells in the United States produced 0.3 trillion cubic feet (8.5 billion cubic metres), 1.6% of US gas production; by 2006, production had more than tripled to 1.1 trillion cubic feet (31 billion cubic metres) per year, 5.9% of US gas production. By 2005, there were 14,990 shale gas wells in the US. [38]
The geographic center of the United States is a point approximately 20 mi (32 km) north of Belle Fourche, South Dakota at 44°58′2.07622″N 103°46′17.60283″W. It has been regarded as such by the United States Coast and Geodetic Survey and the U.S. National Geodetic Survey (NGS) since the additions of Alaska and Hawaii to the United ...
