Investigation of the Crustal Structure in the Middle East from Body-Wave Analysis (POSTPRINT). Annual Report 2

2012 ◽  
Author(s):  
Roland Gritto ◽  
Matthew S. Sibol ◽  
Pierre Caron ◽  
Hafidh A. Ghalib ◽  
Bakir S. Ali ◽  
...  
Keyword(s):  
Middle East ◽  
Crustal Structure ◽  
Annual Report ◽  
Body Wave ◽  
Wave Analysis

Preliminary body-wave analysis of the St. Elias, Alaska earthquake of February 28, 1979

1980 ◽  
Vol 70 (2) ◽  
pp. 419-436
Author(s):  
John Boatwright
Keyword(s):  
New York ◽  
Body Wave ◽  
The Body ◽  
Rupture Velocity ◽  
Wave Analysis ◽  
S Waves ◽  
Initial Event ◽  
Whole Space ◽  
A New Technique ◽  
Alaska Earthquake

abstract Employing a new technique for the body-wave analysis of shallow-focus earthquakes, we have made a preliminary analysis of the St. Elias, Alaska earthquake of February 28, 1979, using five long-period P and S waves recorded at three WWSSN stations and at Palisades, New York. Using a well determined focal mechanism and an average source depth of ≈ 11 km, the interference of the depth phases (i.e., pP and sP, or sS) has been deconvolved from the recorded pulse shapes to obtain velocity and displacement pulse shapes as they would appear if the earthquake had occurred within an infinite medium. These “approximate whole space” pulse shapes indicate that the rupture contained three distinct subevents as well as a small initial event which preceded this subevent sequence by about 7 sec. From the pulse rise times of the subevents, their rupture lengths are estimated as 12, 27, and 17 km, assuming that the subevent rupture velocity was 3 km/sec. Overall, the earthquake ruptured ≈ 60 km to the southeast with an average rupture velocity of 2.2 km/sec. The cumulative body-wave moment for the whole event, 1.2 × 1027 dyne-cm, is substantially smaller than the surface-wave moments reported by Lahr et al. (1979) of 5 × 1027 dyne-cm. The moments of the subevents are estimated to be 0.6, 3.2, and 7.5 × 1026 dyne-cm, respectively.

Body-wave analysis for shallow intraplate earthquakes in the Korean Peninsula and Yellow Sea

1991 ◽  
Vol 192 (3-4) ◽  
pp. 345-357 ◽  
Author(s):  
Myung-Soon Jun
Keyword(s):  
Yellow Sea ◽  
Korean Peninsula ◽  
Body Wave ◽  
Wave Analysis ◽  
Intraplate Earthquakes

Body wave and surface wave analysis of large and great earthquakes along the Eastern Aleutian Arc, 1923-1993: Implications for future events

1994 ◽  
Vol 99 (B6) ◽  
pp. 11643-11662 ◽  
Author(s):  
Charles H. Estabrook ◽  
Klaus H. Jacob ◽  
Lynn R. Sykes
Keyword(s):  
Surface Wave ◽  
Body Wave ◽  
Wave Analysis ◽  
Great Earthquakes ◽  
Aleutian Arc ◽  
Future Events

Money for Nothing? Offsets in the U.S.–Middle East Defense Trade

2009 ◽  
Vol 41 (4) ◽  
pp. 551-553
Author(s):  
Shana Marshall
Keyword(s):  
Middle East ◽  
East Africa ◽  
Annual Report ◽  
Defense Contractors ◽  
Big Business ◽  
Overseas Investment ◽  
Foreign Governments ◽  
Defense Firms ◽  
The U.S ◽  
Weapons Systems

In December 2008, the U.S. Bureau of Industry and Security (BIS) released its thirteenth annual report on offsets in the U.S. defense trade. This chart displays numbers for the BIS category Middle East/Africa, taken from these reports beginning in 1993. Offsets are a variety of industrial and commercial incentives that defense firms provide to foreign governments to facilitate purchases, from coproduction of particular weapons systems to overseas investment. They have become such big business in the Middle East that a system has evolved to allow defense contractors to bank and trade offset credits like any other investment. Unlike ordinary investments, however, offsets represent transfers of substantial resources to authoritarian governments under conditions of near total unaccountability. Because offsets are usually a percentage of the overall contract value, regimes that spend more on weapons get more in offsets.

Crustal structure in the Gangetic Plains of the Indian sub-continent from body waves

1974 ◽  
Vol 64 (3-1) ◽  
pp. 571-579
Author(s):  
R. K. Dube ◽  
J. C. Bhayana
Keyword(s):  
Crustal Structure ◽  
Body Wave ◽  
Bottom Layer ◽  
Body Waves ◽  
P Wave ◽  
Gangetic Plains ◽  
S Waves ◽  
Shear Wave Velocities ◽  
P Wave Velocity ◽  
Peninsular Shield

abstract Crustal structure in the Gangetic Plains of India has been investigated using body-wave data of earthquakes. A three-layered crust has been interpreted, consisting of a top layer of 2.7-km/sec P-wave velocity and 3.7-km thickness, an intermediate layer of 5.64-km/sec velocity and 15.2-km thickness and a bottom layer of 6.49-km/sec velocity and 21.4-km thickness. The average depth of the M discontinuity obtained is 40.3 km. The shear-wave velocities for the Sg, S*, Sn phases are 3.45, 3.85 and 4.61 km/sec, respectively. The velocities of both P and S waves are lower than those obtained for the Peninsular Shield of India.

The crustal structure of the Himalaya: A synthesis

2019 ◽  
Vol 483 (1) ◽  
pp. 483-516 ◽  
Author(s):  
Keith Priestley ◽  
Tak Ho ◽  
Supriyo Mitra
Keyword(s):  
Crustal Structure ◽  
Body Wave ◽  
Foreland Basin ◽  
Indian Plate ◽  
Mountain Range ◽  
Northeastern India ◽  
Himalayan Mountain ◽  
Southern Side ◽  
Tethys Himalaya ◽  
The Himalaya

AbstractThis chapter examines the along-arc variation in the crustal structure of the Himalayan Mountain Range. Using results from published seismological studies, plus large teleseismic body-wave and surface-wave datasets which we analyse, we illustrate the along-arc variation by comparing the crustal properties beneath four representative areas of the Himalayan Mountain Range: the Western Syntaxis, the Garhwal–Kumaon, the Eastern Nepal–Sikkim, and the Bhutan–Northeastern India regions. The Western Syntaxis and the Bhutan–Northeastern India regions have a complicated structure extending far out in front of the main Range, whereas the Central Himalaya appear to have a much simpler structure. The deformation is more distributed beneath the western and eastern ends of the Range, but in general, the crust gradually thickens from c. 40 km on the southern side of the Foreland Basin to c. 80 km beneath the Tethys Himalaya. While the gross crustal structure of much of the Himalaya is becoming better known, our understanding of the internal structure of the Himalaya is still sketchy. The detailed geometry of the Main Himalayan Thrust and the role of the secondary structures on the underthrusting Indian Plate are yet to be characterized satisfactorily.

Sign in / Sign up

Export Citation Format

Share Document