7 resultados para Greenbush


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The wave-theoretical analysis of acoustic and elastic waves refracted by a spherical boundary across which both velocity and density increase abruptly and thence either increase or decrease continuously with depth is formulated in terms of the general problem of waves generated at a steady point source and scattered by a radially heterogeneous spherical body. A displacement potential representation is used for the elastic problem that results in high frequency decoupling of P-SV motion in a spherically symmetric, radially heterogeneous medium. Through the application of an earth-flattening transformation on the radial solution and the Watson transform on the sum over eigenfunctions, the solution to the spherical problem for high frequencies is expressed as a Weyl integral for the corresponding half-space problem in which the effect of boundary curvature maps into an effective positive velocity gradient. The results of both analytical and numerical evaluation of this integral can be summarized as follows for body waves in the crust and upper mantle:

1) In the special case of a critical velocity gradient (a gradient equal and opposite to the effective curvature gradient), the critically refracted wave reduces to the classical head wave for flat, homogeneous layers.

2) For gradients more negative than critical, the amplitude of the critically refracted wave decays more rapidly with distance than the classical head wave.

3) For positive, null, and gradients less negative than critical, the amplitude of the critically refracted wave decays less rapidly with distance than the classical head wave, and at sufficiently large distances, the refracted wave can be adequately described in terms of ray-theoretical diving waves. At intermediate distances from the critical point, the spectral amplitude of the refracted wave is scalloped due to multiple diving wave interference.

These theoretical results applied to published amplitude data for P-waves refracted by the major crustal and upper mantle horizons (the Pg, P*, and Pn travel-time branches) suggest that the 'granitic' upper crust, the 'basaltic' lower crust, and the mantle lid all have negative or near-critical velocity gradients in the tectonically active western United States. On the other hand, the corresponding horizons in the stable eastern United States appear to have null or slightly positive velocity gradients. The distribution of negative and positive velocity gradients correlates closely with high heat flow in tectonic regions and normal heat flow in stable regions. The velocity gradients inferred from the amplitude data are generally consistent with those inferred from ultrasonic measurements of the effects of temperature and pressure on crustal and mantle rocks and probable geothermal gradients. A notable exception is the strong positive velocity gradient in the mantle lid beneath the eastern United States (2 x 10-3 sec-1), which appears to require a compositional gradient to counter the effect of even a small geothermal gradient.

New seismic-refraction data were recorded along a 800 km profile extending due south from the Canadian border across the Columbia Plateau into eastern Oregon. The source for the seismic waves was a series of 20 high-energy chemical explosions detonated by the Canadian government in Greenbush Lake, British Columbia. The first arrivals recorded along this profile are on the Pn travel-time branch. In northern Washington and central Oregon their travel time is described by T = Δ/8.0 + 7.7 sec, but in the Columbia Plateau the Pn arrivals are as much as 0.9 sec early with respect to this line. An interpretation of these Pn arrivals together with later crustal arrivals suggest that the crust under the Columbia Plateau is thinner by about 10 km and has a higher average P-wave velocity than the 35-km-thick, 62-km/sec crust under the granitic-metamorphic terrain of northern Washington. A tentative interpretation of later arrivals recorded beyond 500 km from the shots suggests that a thin 8.4-km/sec horizon may be present in the upper mantle beneath the Columbia Plateau and that this horizon may form the lid to a pronounced low-velocity zone extending to a depth of about 140 km.

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A weekly paper that was published from 1805 to 1814. War related news includes: Page 103 - Weekly Retrospect: Troop movements of Captain Morgan and a company of light dragoons from Niagara to Greenbush; report on the Battle of Queenston Heights including a casualty listing and a mention of the death of Major General Isaac Brock and Colonel McDonald and the American's respect for Brock; British attach of Fort Erie and the Village of Black Rock; the privateer Globe under Captain Murphy returning to Baltimore after capturing a British letter of marque; First Nation / Indian attacks near St. Louis; movements of General W. Harrison and army from Fort Defiance to the rapids of Miama (Miami). The rest of the newspaper contains literary works (poems and translations), essays (including on celibacy), marriages, deaths and other anecdotes. The motto on the front page states: "Visiting Every Flower with Labour Meet, and Gathering all its Treasures, Sweet by Sweet."

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Volumes of interest were published between 1812 and 1815 with articles about the War of 1812. Issue for July 12, 1813 includes an account of the capture of the Chesapeake, report of explosion of the schooner Eagle off New London, report Com. Hardy had detained a smack, was determined to destroy all smacks and other small craft he found, reports of recent events at Malden, Fort George, head of the Lake, Sacketts Harbour, two reports of attack on Hampton, report of British attack near point of Nansemond River/Craney Island, second report of battle on/near Craney Island, additional report of attack at Hampton, marine news from Baltimore, report that sickness rampant throughout Army, many deaths reported, report that British were fortifying Brownstown, but deserters from British believe Michigan could be retaken by 3000 troops, report Gen. Boyd remained at Fort George to supervise repair of fortifications, report British reinforced from Kingston in Niagara and in Malden, report Gen. Hampton arrived at Albany on way to Burlington, report Gen. Parker left Albany, headed to Burlington, report of 400 men marching from Greenbush to the frontier, report of battles at Stoney Creek, 40 Mile Creek, report that Gen. Boyd lost an action with British in which 8 to 10 hundred men killed and taken from Americans, reports British had captured stores at Black Rock, Sodus, and Oswego, report of British victory in a battle 5 miles from Queenston, troop strength under Dearborn in Niagara reported between 2 and 3 thousand, additional reports of Battle of Beaverdams, reports Dearborn had resumed command, after lengthy illness, Gen. Boyd remained at Fort George, reports natives had been sieging Fort Wayne.

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The Second U.S. Regiment of Light Dragoons was formed in January 1812. In March of 1814, it merged with the First U.S. Regiment of Light Dragoons to form the Regiment of Light Dragoons.

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An orderly book of the Second Regiment of U.S. Dragoons, New York, dated August 14, 1812-July 29, 1813. The book contains orders pertaining to day-to-day military matters, such as punishments for disobedience, court-martial proceedings, camp rules and regulations, and guidelines for interacting with civilians in the vicinity of the camp. The Regiment was stationed at various locations in upstate New York and Canada, including Greenbush, Albany, Sackets Harbor, Utica, Geneva, Fort Niagara and Fort George. General Henry Dearborn originally commanded the Regiment at Greenbush. Names noted in this book include:E. Beebe, Deputy Adjt. General; William King, Capt. 15th; John Chandler, General ;W. Gamewood, Major ;James Burns, Colonel;John Woodford, Major; Andrew McDowell, Capt.; Abm. Gustis, Major; C.W. Hunter, Brigade Major; Selden, Captain; Holland, Captain; Harris, Captain; Clarkson, Lieutenant; Johnson, Lieutenant; Robert Craig, Adjt.; R.G. Hith, A.A. General. Also included with the orderly book are a monthly return form, a contract for medical services, and a bonus pay voucher for Thomas Blunt. The monthly return form is partially completed and dated January 1813 at Greenbush, New York. It is signed by Captain Jonas Holland. The contract is dated May 20, 1812, between John Dodge, physician and surgeon, and Jonas Holland. The contract describes the services required of the physician and the salary to be paid. The bonus pay voucher is dated April 25, 1813, for $8.00 paid to Thomas Blunt by Captain Jonas Holland for 'enlisting into the army of the United States for five years'.

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This layer is a georeferenced raster image of the historic paper map entitled: Topographical map of the county of Penobscot Maine, from surveys under the direction of H.F. Walling; field work under the direction of L.H. Eaton. It was published by Lee & Marsh in 1859, Scale 1:80,000. This layer is image 1 of 2 total images, representing the southwest portion of the four sheet source map. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Universal Transverse Mercator projection (UTM Zone 19N, meters, NAD1983). All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as roads, railroads, drainage, public buildings, schools, churches, cemeteries, industry locations (e.g. mills, factories, mines, etc.), private buildings with names of property owners, town boundaries, and more. Relief shown by hachures. It includes many cadastral insets of individual county towns and villages. It also includes illustrations, business directories, and tables of statistics and distances.This layer is part of a selection of digitally scanned and georeferenced historic maps of New England from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of regions, originators, ground condition dates, scales, and map purposes.