Why not even Minnesota is safe from quakes
Minnesota earned its 'blue mark' in the 1975 Morris earthquake, which had its epicenter in the western part of the state.
- Californians, want to run away from the Big One? Head for Minnesota.
- As this map shows, the Gopher State is the least likely to be hit by earthquakes.
- Choose your new home wisely, though: even Minnesota has one earthquake-sensitive spot.
Not if, but when
The Long Beach earthquake hit on 10 March 1933 with an estimated magnitude of 6.25 on the Richter scale.
Image: Nathan Callahan, CC BY 2.0
It's not if, but when: Californians live with the certainty that someday, the Big One will hit.
The Big One is an earthquake with a magnitude of at least 7.8 on the Richter scale. Because of the plate tectonics at work under California, big quakes like that hit the area every 45 to 230 years.
The last one was more than 160 years ago. That's why paleoseismologist Kerry Sieh says the next one is likely to happen "within the lifetime of children in primary school today."
Here's how the United States Geological Survey (USGS) rates the hazard of a major earthquake in California in the next 30 years:
- 60% chance of a 6.7-magnitude quake.
- 46% chance of a 7.0-magnitude quake.
- 31% chance of a 7.5-magnitude quake.
The earthquake hazard map of the United States.
Image: USGS, public domain
The Pacific coast is purple: the highest hazard. The entire west is shaded in colors denoting declining hazard. Only relatively small parts of the country are covered by the zone of lowest hazard:
- central and southern Texas;
- most of Florida, Michigan, Wisconsin, Iowa, and North Dakota;
- sizable chunks of Kansas, Nebraska, Montana, and South Dakota;
- and tiny bits of Alaska, Colorado, New Mexico, Louisiana, Arkansas, Alabama, and Georgia.
One state seems hazard-free, but that's only until you notice the blue spot in Minnesota's western bulge.
So, what do these colors actually denote? Earthquake hazard maps show the potential shaking hazard from future earthquakes.
The USGS defines earthquake hazard as the probability of ground motion over 50 years. That probability is determined by a region's geology and earthquake history.
The location of fault lines alone is not enough to determine quake hazard: a large earthquake can produce tremors at a relatively large distance from the actual fault line.
The colors on this earthquake hazard map correspond to Seismic Design Categories (SDCs), which reflect the likelihood of seismic activity leading to ground motion of various intensities.
Damage caused by the 6.0-magnitude Napa County earthquake of 24 August 2014.
Image: Matthew Keys, CC BY-SA 4.0
These SDCs are used to determine the level of seismic resistance required in building design and building codes.
- SDC level A (grey): Very small probability of experiencing damaging earthquake effects.
- SDC level B (blue): Moderate-intensity shaking possible. Such shaking will be felt by all. Many will be frightened. Some furniture will be moved and some plaster will fall. Overall damage will be slight.
- SDC level C (green): Strong shaking possible. Damage will be negligible in well-designed and well-constructed buildings; considerable in poorly-built structures.
- SDC levels D0 (yellow), D1 (orange) and D2 (red): Very strong shaking possible. Damage will be slight in specially designed structures; considerable in ordinary substantial buildings, with partial collapse; and great in poorly built structures.
- SDC level E (purple): This is near major active faults capable of producing the most intense shaking. Even in specially designed structures, the damage will be considerable. The shaking is intense enough to completely destroy buildings.
The Morris quake
Minnesota earned its blue spot in 1975.
Image: USGS, public domain
This earthquake hazard map is not a snapshot of the past, but an evolving prediction of the future. The map is adapted as geological knowledge increases. But it is also partly based on past events – or more precisely the likelihood of their recurrence.
Minnesota earned its blue spot from the 1975 Morris earthquake. With its epicenter in Stevens County, it struck at around 10 am on July 9th of that year and had a magnitude of 4.6. It was the first seismic event recorded in the state since the Staples quake of 1917, and it was felt as far afield as the eastern Dakotas and northern Iowa.
Near the epicenter, plaster cracked and pictures fell off walls. In the town of Morris, two homes suffered damage to their foundations. Not quite California-sized, but for lack of comparison, probably Big Enough for the locals.
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Whether or not women think beards are sexy has to do with "moral disgust"
- A new study found that women perceive men with facial hair to be more attractive as well as physically and socially dominant.
- Women tend to associate more masculine faces with physical strength, social assertiveness, and formidability.
- Women who display higher levels of "moral disgust," or feelings of repugnance toward taboo behaviors, are more likely to prefer hairy faces.
Beards and perceptions of masculinity<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjU5OTg0MC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NzkxMjM3N30.cH-GqNwP5GVqvstgJWAhBPn1B_lYpVEAI0I7iax7EQw/img.jpg?width=1245&coordinates=0%2C1900%2C0%2C849&height=700" id="caae6" class="rm-shortcode" data-rm-shortcode-id="cb0a355a4e8e1899789bc45f3f7aef56" data-rm-shortcode-name="rebelmouse-image" />
Photo Credit: Wikimedia<p>The study used 919 American (mostly white) women ages 18-70 who rated 30 pictures of men they were shown with various stages of facial hair growth. The photographs depicted men with faces that had been digitally altered to look more feminine or more masculine, with a beard and without a beard. The women rated the men according to perceived attractiveness for long-term and short-term relationships. The study found that the more facial hair the men had, the higher the men were rated on their attractiveness, particularly for their suitability for a long-term relationship.</p><p>Part of this might be attributed to facial masculinity — i.e. protruding brow ridge, wide cheekbones, thick jawline, and deeply set narrow eyes — which conveys information to a woman about a man's underlying health and formidability. Women tend to associate more masculine faces with physical strength and social assertiveness. It can also indicate a man with a superior immune response. The researchers suggested that their findings favoring bearded men could be due to the fact that facial hair enhances the masculine facial features on a man's face, like creating the illusion of a thicker jaw line. This could communicate direct benefits to women like resources and protection that would enhance survival among mothers and their infants. In other words, while a beard doesn't mean superior genetics in and of itself, it might be a primitive, ornamental way of saying, "Hey girl, I'm a testosterone-fueled lean, mean, pathogen fighting machine." <br></p><p>It could also be that a beard becomes its own destiny. The researchers in this study cite prior research that found that by growing a beard, men felt more masculine and had higher levels of serum testosterone, which was linked to a higher level of social dominance. They also tended to subscribe to more old-school beliefs about gender roles in their relationships with women as compared to men with clean-shaven faces.<span></span><br></p>
What does disgust have to do with beard preference?<p>Obviously, not all women dig beards. The researchers were particularly interested in what traits make a women prefer bearded men over clean-shaven faces. They looked into several factors including a woman's disgust levels on various concepts, her desire to become pregnant, and her exposure to facial hair in her personal life. </p><p>According to the study, women who were not into facial hair were turned-off by potential parasites or other critters they imagined could be in the hair or skin. Women ranking high on this "ectoparasite disgust" scale might have viewed beards as a sign of poor grooming habits. However, women who ranked higher in levels of "pathogen" did find the bearded men to be desirable, possibly because they perceived beards as a signal of good health and immune function. An intriguing discovery in the study was links to morality. Women who displayed higher levels of "moral disgust," or feelings of repugnance toward taboo behaviors, were more likely to prefer hairy faces. The authors opined that this could reflect a link between beardedness, politically conservative outlooks, and traditional views regarding performances of masculinity in heterosexual relationships.</p>
Additional findings<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjU5OTg1My9vcmlnaW4uZ2lmIiwiZXhwaXJlc19hdCI6MTYyNDI1NjUyOX0.P9B8WbmJR0q4nfzYZKbuNSA-2SAigVWJgrQE-_Gxlds/img.gif?width=980" id="49143" class="rm-shortcode" data-rm-shortcode-id="2ed3b1d6f20fc170bf2974646e565e8d" data-rm-shortcode-name="rebelmouse-image" />Giphy<p>The correlations that existed between married and single women's rating on the attractiveness of beards were not particularly clear, although the researchers noted that single and married women who wanted children tended to find beards more attractive than the women who didn't want children. They also found that women with bearded husbands found beards to be more attractive, which might indicate that social exposure to beards influences how desirable they are perceived of as being. Or it could be that men with wives who like beards grow beards.</p><p>It's important to note that culture plays a huge role in how attractive women perceive certain male characteristics as being. This study looked at a small, culturally specific group of American women, so no big, universal claims should be made about masculinity, facial hair, and male desirability to women. However, research like this is important in highlighting how human grooming decisions are driven by much more than fashion trends. Sociobiological, economic, and ecological factors all play a part in the way we choose to present ourselves.</p>
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