Earthquake strikes central Indiana; felt in Bloomington, Columbus and Seymour

[Project Grudge]

Source: The Courier-Journal

The U.S. Geological Survey reported a 4.2 magnitude earthquake centered about 13 miles southeast of Kokomo at 7:55 a.m. today.

Reports to USGS suggest the quake was felt as far south as Martinsville and as far west as New Castle. People on the Northeastside of Indianapolis and in Noblesville said items were shaking on shelves.

Read more: http://www.courier-journal.com/article/20101230/NEWS02/312300046/Earthquake+strikes+central+Indiana++felt+in+Bloomington++Columbus+and+Seymour

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Earthquake in Indiana....weird.

[AngryOldDem]

1. Weird? Not really.

They occur from time to time. There are a lot of small faults around the Indiana/Ohio region that shake from time to time. A 4.2 is kind of a strong one for these parts, but that's not really rare, either.

I live just north of Indianapolis and I didn't feel anything, although my son said he did. A lot of people have said their pets were very agitated about a half-hour before it happened.

[Ex Lurker]

2. are these faults connected to the New Madrid fault?

[AngryOldDem]

3. No.

There are a lot of small faults around here. Northern Ohio gets a lot (comparatively speaking) of tremors, most of which are too light to be felt.

Every so often the media make a big deal about the New Madrid -- about what would happen, etc. -- because I guess it's coming due here soon. We'll probably be hearing about that on the news today.

No real reports of damage other than things falling off shelves, pots getting busted, etc. -- people close by said it sounded like a train derailment.

[Baclava]

8. who can really tell?

[AngryOldDem]

9. Because the suspected faults are nowhere near the New Madrid.

http://www.indystar.com/article/20101231/LOCAL/12310327/Scientists-ask-which-fault-fault-yesterday-s-3-8-quake?odyssey=tab|topnews|text|IndyStar.com

<<It's not even clear which fault line caused the quake, although John C. Steinmetz has an idea.

Steinmetz, director of the Indiana Geological Survey research institute at IU, thinks the Sharpsville Fault, which is named after the Indiana town and runs from Tipton County to Howard County, likely played a role. The fault is within a mile of the quake's epicenter.

But, Hamburger said, the culprit also could be a fault scientists have not yet discovered. He said the quake likely originated in the crystalline rock beneath a surface layer of sedimentary rock -- a largely unknown territory 3 to 9 miles down.<<

There is also a Fortville fault that runs roughly southeast of the Kokomo area, which some originally thought was the culprit. These faults have been relatively inactive, which is why this came as such a surprise.

[Project Grudge]

5. Apparently, the Indianapolis Star says these quakes are rare

"But if it left a few Hoosiers a bit shaken, it left scientists with a mystery: What fault's at fault? The answer may take weeks, months or even years of research.

What was certain is that this particular quake was in rare company... But -- except for two unconfirmed reports from before World War II -- no earthquake has ever been recorded in north-central Indiana, scientists said.

Until 7:55 a.m. Thursday.

"It's a big surprise," said Michael Hamburger, a professor of geological sciences at Indiana University."

Scientists ask which fault is at fault for yesterday's 3.8 quake


---As I said, weird....

[AngryOldDem]

4. Update: USGS has revised the magnitude down to 3.8 n/t

[alfredo]

6. My friend an earthquake zone veteran slept through it, but

did have a dream about an earthquake.

[alfredo]

7. Story about ancient fault line being reactivated.

http://www.ldeo.columbia.edu/news-events/lamont-doherty-research-suggests-ancient-fault-lines-indiana-have-been-re-activated


Image of Indiana geology. Black lines are fault lines.