The St-Donat, Quebec, earthquake sequence of February 18–23,1978

R. B. Horner; R. J. Wetmiller; H. S. Hasegawa

doi:10.1139/e79-175

The St-Donat, Quebec, earthquake sequence of February 18–23,1978

Canadian Journal of Earth Sciences ◽

10.1139/e79-175 ◽

1979 ◽

Vol 16 (9) ◽

pp. 1892-1898 ◽

Cited By ~ 16

Author(s):

R. B. Horner ◽

R. J. Wetmiller ◽

H. S. Hasegawa

Keyword(s):

New York ◽

Main Shock ◽

New York State ◽

Focal Depth ◽

Maximum Intensity ◽

Systematic Change ◽

Aftershock Activity ◽

Active Volume ◽

Significant Area ◽

Recent Earthquakes

The St-Donat earthquake of February 18, 1978, occurred in a diffuse zone of significant seismicity in western Quebec. A field survey detected two aftershocks ([Formula: see text]) in a 3 day period following the magnitude mb(Lg) 4.1 main shock. These were followed by a magnitude mb(Lg) 3.4 earthquake on February 23, after the field stations were removed. Main shock and aftershock activity occurred within a small active volume located at 46 °19.2′N, 74°06.6′W, depth 7 km, with an estimated uncertainty of 1 km on all three hypocentral parameters. The main shock seismic moment was calculated to be 0.8 × 1022 dyne∙cm (8 × 1022 μN∙cm).The tremor was felt over an area of 70 000 km2 in western Quebec, eastern Ontario, and northern New York State with a maximum radius of perceptibility of 185 km and a maximum intensity of V in the St-Donat area. A comparison of the isoseismals of this and three other recent earthquakes of magnitude near 4 suggests a variation of maximum intensity inversely with focal depth; a significant area of intensity V is only observed when the focal depth is less than 10 km. There is also an indication of a systematic change in focal depths across the western Quebec zone, from shallow (upper crustal) depths north of Montreal to deeper (midcrustal) depths north of Ottawa.The P-nodal solution indicates almost pure thrust motion on a plane striking N20°W and dipping either 40°NE or 50°SW. The deviatoric compression axis is nearly horizontal, in a west-southwest direction. Similar results from the 1975 Maniwaki, Quebec, earthquake suggest that a uniform stress condition exists throughout western Quebec.

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Source parameters of the June 13, 1967 earthquake near Lake Ontario, New York State

Canadian Journal of Earth Sciences ◽

10.1139/e77-229 ◽

1977 ◽

Vol 14 (11) ◽

pp. 2651-2657 ◽

Cited By ~ 3

Author(s):

Michio Hashizume ◽

Nagakoto Tange

Keyword(s):

New York ◽

Surface Wave ◽

Epicentral Distance ◽

Source Parameters ◽

New York State ◽

Focal Depth ◽

Lake Ontario ◽

Strike Slip ◽

York State ◽

Long Period

Source parameters of an earthquake with magnitude mb = 4.4 were determined by using surface waves. Small but clear surface wave signals were observed on long period records gathered from seismograph stations within an epicentral distance of about 2000 km. The focal mechanism was determined to be of strike-slip type with the maximum and the minimum compression axes trending NNW–SSE and ENE–WSW, respectively. The focal depth was determined to be near either 3 or 20 km.

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Fault parameters of the St. Elias, Alaska, earthquake of February 28, 1979

Bulletin of the Seismological Society of America ◽

10.1785/bssa0700051651 ◽

1980 ◽

Vol 70 (5) ◽

pp. 1651-1660

Author(s):

H. S. Hasegawa ◽

J. C. Lahr ◽

C. D. Stephens

Keyword(s):

Main Shock ◽

Focal Depth ◽

P Wave ◽

Large Magnitude ◽

Aftershock Activity ◽

Nodal Plane ◽

Fault Parameters ◽

Fault Length ◽

Interplate Earthquakes ◽

Alaska Earthquake

abstract Fault parameters of the Ms 7.1 St. Elias, Alaska, earthquake of February 28, 1979, are determined from an analysis of P-wave first motions, fundamental-mode surface waves, and aftershock data. The preferred P-wave nodal plane has a shallow (12°) angle of dip and indicates underthrusting in a northerly (N13°W) direction, which is also close to the azimuth (N8°W) of the deviatoric compression (P) vector. Aftershock activity during the 24-hr interval immediately following the main shock extends over an area of 3200 km2, which is taken to represent the fault area of the main shock. Because aftershock activity outlines a fault area with nonrectangular geometry, fault length (50 to 80 km) and width (50 to 65 km) are not well defined. Estimates of focal depth from aftershock activity fall in the range 10 to 20 km, which surface-wave analysis is unable to restrict further. For the main shock, seismic moment, Mo, is 2.5 × 1027 dyne-cm (0.25 × 1021 N.m) and average dislocation, 2 meters. Average rupture velocity falls in the range 2.5 to 3 km/sec. Apparent stress, ησ, is 5 bars (0.5 MPa) and stress drop, Δσ, 35 bars (3.5 MPa). These values are considered typical of large-magnitude interplate earthquakes.

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Eliezer Ben-Rafael, Crisis and Transformation: The Kibbutz at Century's End, New York: State University of New York Press, 1997, £17.25, xii+282 pp. (ISBN 0-7914-3225-4).

Sociology ◽

10.1017/s0038038598210133 ◽

1998 ◽

Vol 32 (3) ◽

pp. 613-637

Author(s):

CHRISTOPHER WARHURST

Keyword(s):

New York ◽

New York State ◽

State University ◽

York State

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Cultural Competence Needed to Distinguish Disorder from Difference: Beyond Kumbaya

Perspectives on Communication Disorders and Sciences in Culturally and Linguistically Diverse Populations ◽

10.1044/cds22.2.64 ◽

2015 ◽

Vol 22 (2) ◽

pp. 64-76 ◽

Cited By ~ 7

Author(s):

Catherine J. Crowley ◽

Kristin Guest ◽

Kenay Sudler

Keyword(s):

New York ◽

New York City ◽

Public Schools ◽

Cultural Competence ◽

York City ◽

Cultural Sensitivity ◽

Graduate Program ◽

Language Disorder ◽

New York State ◽

Deep Understanding

What does it mean to have true cultural competence as an speech-language pathologist (SLP)? In some areas of practice it may be enough to develop a perspective that values the expectations and identity of our clients and see them as partners in the therapeutic process. But when clinicians are asked to distinguish a language difference from a language disorder, cultural sensitivity is not enough. Rather, in these cases, cultural competence requires knowledge and skills in gathering data about a student's cultural and linguistic background and analyzing the student's language samples from that perspective. This article describes one American Speech-Language-Hearing Association (ASHA)-accredited graduate program in speech-language pathology and its approach to putting students on the path to becoming culturally competent SLPs, including challenges faced along the way. At Teachers College, Columbia University (TC) the program infuses knowledge of bilingualism and multiculturalism throughout the curriculum and offers bilingual students the opportunity to receive New York State certification as bilingual clinicians. Graduate students must demonstrate a deep understanding of the grammar of Standard American English and other varieties of English particularly those spoken in and around New York City. Two recent graduates of this graduate program contribute their perspectives on continuing to develop cultural competence while working with diverse students in New York City public schools.

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