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Wolf pack

2008-07-05T20:14:27Z

62.121.45.84:

The term '''wolf pack''' refers to the mass-attack tactics against [[convoy]]s used by [[Germany|German]] [[U-boat]]s of the [[Kriegsmarine]] during the [[Second Battle of the Atlantic|Battle of the Atlantic]] and [[submarine]]s of the [[United States Navy]] against [[Japan]]ese shipping in the [[Pacific Ocean]] in [[World War II]].

[[Karl Dönitz]] used the term ''Rudel'' to describe his strategy of submarine warfare—''Rudel'' translates best as "pack" of animals and has become known in [[English language|English]] as "wolf pack" (''Wolfsrudel''), a more accurate metaphoric, but not literal, translation.

U-boat movements were controlled by the ''[[Befehlshaber der Unterseeboote]]'' (BdU; English translation: "Commander of Submarines") much more closely than American submarines, which were given tremendous independence once on patrol. Accordingly, U-boats usually patrolled separately, often strung out in co-ordinated lines across likely convoy routes (usually merchants and small vulnerable destroyers), only being ordered to congregate after one located a convoy and alerted the BdU, so a ''Rudel'' consisted of as many [[U-boat]]s as could reach the scene of the attack. With the exception of the orders given by the BdU, U-Boat commanders could attack as they saw fit. Often the U-Boat commanders were given a probable number of U-Boats that would show up, and then when they were in contact with the convoy, make call signs to see how many had arrived. If the number was sufficient, or if the threat of increased escorts was a possibility, they would attack.

American wolf packs, officially called ''coordinated attack groups'', usually comprised three boats that patrolled in close company and organized before they left port under the command of the senior captain of the three. [[Charles Momsen|"Swede" Momsen]] devised the tactics and led the first American wolf pack from Midway on 1 October, 1943 - {{USS|Cero|SS-225|3}}, {{USS|Shad|SS-235|3}}, and {{USS|Grayback|SS-208|3}}.

Although the wolf packs proved a serious threat to Allied shipping, the Allies developed countermeasures to turn the U-boat organization against itself. Most notably was the fact that wolf packs required extensive [[radio]] communication to coordinate the attacks. This left the U-boats vulnerable to a device called the [[High Frequency Direction Finder]] (HF/DF or "Huff-Duff") which allowed Allied naval forces to determine the location of the enemy boats transmitting and attack them. Also, effective air cover, both long-range planes with radar, and [[escort carrier]]s and [[blimp]]s, allowed U-boats to be spotted as they shadowed a convoy (waiting for the cover of night to attack). The destroyers of the Atlantic also used depth charges and other small mines which could be dropped off the ships' side.

Wolf packs fell out of use during the [[Cold War]]: modern submarines have far better weapons and underwater speed than those of [[World War II]], so there is no need for them to operate in large groups. Instead, the [[United States Navy]] deploys its attack submarines on individual patrols, with the exception of one or (rarely) two attack submarines in each carrier group. American ballistic missile submarines have always operated alone. (Soviet ballistic missile submarines operate in well-protected [[bastion (naval)|bastion]]s.) However, with the opening shots of the [[Iraq War]] in March, 2003, the term "wolf pack" was brought back into use to describe the fleet of American and British [[nuclear submarine]]s which operated together in the [[Red Sea]], firing [[BGM-109 Tomahawk|Tomahawk missiles]] at [[Iraq]]i targets. [[USS Providence (SSN-719)|USS ''Providence'']] was the first boat to fire its entire load of missiles and earn the nickname "Big Dog of the Red Sea Wolf Pack."

Recently the name "wolf pack" has been assigned to Iranian missile boat tactis in an hypothetical clash with [[U.S. Navy]];a massive attack of small-size boat armed with missiles and torpedoes on a single (or few) ships in order to overrun or saturate the [[Aegis]]
system;in such attacks even suicide boat could be deployed.

== See also ==
* [[Convoy SC-7]] for an account of one of the first Allied convoys to suffer a wolf pack attack

== References ==
* Karl Dönitz, ''Memoirs: Ten Years and Twenty Days'' (New York: World Publishing Company, 1958)

* Peter Maas, ''The Terrible Hours: The Man Behind the Greatest Submarine Rescue in History'' (HarperCollins New York, 1999)

* E. B. Potter and Chester W. Nimitz, eds; ''Sea Power: A Naval History'' (Englewood Cliffs, N.J.: Prentice-Hall, 1960)

{{Uboat}}

[[Category:Naval warfare tactics]]
[[Category:Wolfpacks of World War II|*]]

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[[da:Ulvekobbel]]
[[de:Rudeltaktik]]
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[[ja:群狼作戦]]
[[pl:Wilcze stado]]
[[sk:Taktika vlčích svoriek]]
[[sr:Вучји чопор]]
[[tr:Wolfpack]]

About engineering geology

2006-06-02T12:19:06Z

62.121.88.128:

'''Engineering Geology''' is the application of the science of [[geology]] to the understanding of [[geologic]] phenomena and the engineering solution of [[geologic hazards]] and other geologic problems for society. Engineering geologic studies may be performed during the planning, [[environmental impact analysis]], [[civil engineering]] [[design]], [[value engineering]] and construction phases of public and private works projects, and during post-construction and [[forensic]] phases of projects. Engineering geologic studies are performed by a [[geologist]] or [[engineering geologist]] educated, professionally trained and skilled at the recognition and analysis of [[geologic hazards]] and adverse geologic conditions. Their overall objective is the protection of people and property against damage and the solution of geologic problems.

Engineering geologic studies may be performed
*for residential, commercial and industrial developments;
*for governmental and [[military]] installations;
*for public works such as a [[power plant]], [[wind turbine]], electrical [[transmission line]], [[sewage treatment]] plant, [[water treatment]] plant, [[pipeline]] ([[aqueduct]], [[sewer]], [[outfall]]), [[tunnel]], [[trenchless]] construction, [[canal]], [[dam]], [[reservoir (water)|reservoir]], building, [[railroad]], [[transit]], [[highway]], [[bridge]], [[seismic retrofit]], airport and park;
*for [[Mining|mine]] and [[quarry]] excavations, [[mine tailing dam]], [[mine reclamation]] and mine [[tunneling]];
*for [[wetland]] and [[habitat restoration]] program;
*for [[coastal]] engineering, [[sand replenishment]], [[bluff]] or [[sea cliff]] stability, [[harbor]], [[pier]] and waterfront development;
*for offshore [[outfall]], [[drilling platform]] and [[sub-sea pipeline]], sub-sea cable; and
*for other types of facilities.

It is important to keep in mind that in [[engineering geology]], there are only two important types of [[Rock (geology)|rock]]: those which can be moved by a [[bulldozer]], and those which require [[dynamite]].

==Geologic Hazards==
Typical [[geologic hazards]] evaluated by an [[engineering geologist]] include
*[[fault rupture]] on seismically active [[faults]] ;
*[[seismic]] and [[earthquake]] hazards (ground shaking, [[liquefaction]], [[lurching]],[[lateral spreading]], [[tsunami]] and [[seiche]] events);
*[[landslide]], [[mudflow]], [[rock fall]] and [[avalanche]] hazards ;
*[[unstable slopes]] and [[slope stability]];
*[[erosion]];
*[[slaking]] and [[heave]] of geologic formations;
*ground [[subsidence]] (such as due to [[ground water]] withdrawal, [[sinkhole]] collapse, [[cave]] collapse, decomposition of organic soils, and [[tectonic]] movement);
*[[volcanic]] hazards ([[volcanic eruption]]s, [[hot springs]], [[pyroclastic flows]], [[debris flows]], [[gas emissions]], volcanic [[earthquakes]]);
*collapsible soils;
*shallow ground water/seepage; and
*other types of geologic constraints.

An engineering geologist or [[geophysicist]] may be called upon to evaluate the [[excavatability]] (i.e. [[rippability]]) of earth (rock) materials to assess the need for pre-[[blasting]] during earthwork construction, as well as associated impacts due to [[vibration]] during blasting on projects.

=='''Methods and Reporting'''==

The methods used by [[engineering geologist]]s in their studies include
*geologic field [[mapping]] of geologic structures, geologic formations, soil units and hazards;
*the review of geologic literature, geologic maps, geotechnical reports, engineering plans, environmental reports, stereoscopic [[aerial photograph]]s, remote sensing data, [[Global Positioning System]] (GPS) data, topographic maps and [[satellite]] imagery;
*the excavation, sampling and logging of earth/rock materials in drilled borings, backhoe test pits and trenches, fault trenching, and bulldozer pits;
*[[geophysical]] surveys (such as [[seismic refraction]] traverses, [[resistivity]] surveys, [[ground penetrating radar]] (GPR) surveys, [[magnetometer]] surveys, [[electromagnetic]] surveys, high-resolution sub-bottom profiling, and other geophysical methods); and
*other methods.
The field work is typically culminated in analysis of the data and the preparation of an engineering geologic report, fault hazard or seismic hazard report, geophysical report, [[ground water]] resource report or [[hydrogeology|hydrogeologic]] report. The engineering geologic report is often prepared in conjunction with a [[geotechnical engineering]] report by a geotechnical engineer. The report describes the objectives, methodology, references cited, tests performed, findings and recommendations. Engineering geologists provide geologic data on topograpic maps, aerial photographs, geologic maps, [[Geographic_information_system|Geographic Information System]] (GIS) maps, or other map bases.

=='''See also'''==
* [[List of publications in geology#Engineering geology| Important publications in engineering geology]]

[[Category:Geology]]
[[Category:Engineering]]

[[pt:Geologia de engenharia]]
[[it:Geologia Applicata]]
[[pl:Geologia inżynierska]]

Engineering geology

2006-06-02T12:19:06Z

62.121.88.128: