Tag Archives: crack

Eight Seconds of Terror

A JPL Scientist Reflects on L.A.’s Last Big Quake

Twenty years ago this week, in the predawn darkness of Jan. 17, 1994, at five seconds before 4:31 a.m. PST, the ground ruptured violently on a blind thrust fault (a crack in Earth’s crust that does not reach the surface) about 11 miles (18 kilometers) beneath Reseda, in California’s San Fernando Valley about 20 miles (31 kilometers) northwest of downtown Los Angeles. The resulting magnitude 6.7 earthquake, known as the Northridge earthquake, became the first large quake to strike directly under an urban area in the United States since the 1933 magnitude 6.4 earthquake in Long Beach, Calif. (more…)

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Rise in Teen Marijuana Use Stalls, Use of Synthetic Marijuana and ‘Bath Salts’ is Very Low

ANN ARBOR — National samples of 45,000 to 50,000 students in three grades (8, 10, and 12) have been surveyed every year since 1991 as part of the nationwide Monitoring the Future study. Among the most important findings from this year’s survey of U.S. secondary school students are the following:

Marijuana. After four straight years of increasing use among teens, annual marijuana use showed no further increase in any of the three grades surveyed in 2012. The 2012 annual prevalence rates (i.e., percent using in the prior 12 months) were 11%, 28%, and 36% for 8th, 10th, and 12th graders, respectively. (Among the 8th graders there was a modest decline across the past two years—from 13.7% in 2010 to 11.4% in 2012—that reached statistical significance.) (more…)

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American Teens Are Less Likely Than European Teens to Use Cigarettes and Alcohol, but More Likely to Use Illicit Drugs

ANN ARBOR, Mich.— The U.S. had the second-lowest proportion of students who used tobacco and alcohol compared to their counterparts in 36 European countries, a new report indicates.

The results originate from coordinated school surveys about substance use from more than 100,000 students in some of the largest countries in Europe like Germany, France and Italy, as well as many smaller ones from both Eastern and Western Europe.

Because the methods and measures are largely modeled after the University of Michigan’s Monitoring the Future surveys in this country, comparisons are possible between the U.S. and European results. The 15- and 16-year-old students, who were drawn in nationally representative samples in almost all of the 36 countries, were surveyed last spring. American 10th graders in the 2011 Monitoring the Future studies are of the same age, so comparisons are possible. (more…)

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