Texas earthquakes! No, really

[See report on January 6, 2014 series of earthquakes here.]

Texas earthquake, 2.7 magnitude – Saturday, November 01, 2008 at 11:54:30 (UTC) – Coordinated Universal Time,  Saturday, November 01, 2008 at 06:54:30 AM local time at epicenter – epicenter in Las Colinas, Irving, Texas.

Some Texans hope for a Texas earthquake on Tuesday.  Four years ago Dallas County voters resisted the Red Tide, voting for a Democrat in every judicial race on the ballot where a Democrat was running, electing a Democrat for sheriff, and putting a Democrat in as District Attorney for the first time since Noah disembarked the boat on the mountain in Turkey.

Voters in Dallas County, Harris County (Houston), and Bexar County (San Antonio) seem prepared to do it again.

That would be a virtual earthquake.

Meanwhile, the Dallas area has had a series of real earthquakes over in the end of this week. The biggest was about 3.0 on the Richter Scales, barely detectable to most people.  But this is big stuff around here.  We sit on some of the most geologically stable land in North America.  Earthquakes are rare, and usually small.

We’ve had eight quakes in the past two days.  Despite their low magnitude, a few people are worried.  Students are interested, not least because they worry about a destructive quake.  For people who live in Tornado Alley, fears of earthquakes seem odd, at least to those of us who grew up in more earthquake-prone provinces.

Here’s the list from the U.S. Geological Survey (USGS):

Earthquake List for Map Centered at 33°N, 97°W

 

Update time = Sun Nov 2 4:00:04 UTC 2008

Here are the earthquakes in the Map Centered at 33°N, 97°W area (go see the map), most recent at the top.  (Some early events may be obscured by later ones.)  Click on the underlined portion of an earthquake record in the list below for more information.

	MAG	UTC DATE-TIME y/m/d h:m:s	LAT deg	LON deg	DEPTH km	LOCATION
MAP	2.7	2008/11/01 11:54:30	32.873	-96.968	5.0	3 km ( 2 mi) N of Irving, TX
MAP	2.5	2008/11/01 11:53:46	32.766	-97.035	5.0	6 km ( 4 mi) NNW of Grand Prairie, TX
MAP	2.9	2008/10/31 21:01:01	32.788	-97.028	5.0	8 km ( 5 mi) N of Grand Prairie, TX
MAP	2.9	2008/10/31 20:54:18	32.831	-97.028	5.0	6 km ( 4 mi) WSW of Irving, TX
MAP	2.9	2008/10/31 07:58:23	32.832	-97.012	5.0	5 km ( 3 mi) WSW of Irving, TX
MAP	2.6	2008/10/31 05:33:45	32.871	-96.971	5.0	3 km ( 2 mi) N of Irving, TX
MAP	3.0	2008/10/31 05:01:54	32.836	-97.029	5.0	6 km ( 4 mi) WSW of Irving, TX
MAP	2.6	2008/10/31 04:25:52	32.800	-97.016	5.0	7 km ( 4 mi) SW of Irving, TX

Map of Irving, Texas, showing the epicenter of an earthquake November 1, 2008 – near the development known as Las Colinas

Two fault lines run under the Dallas-Fort Worth area, the Mexia and Balcones faults — but both are said to be “inactive.”  Earthquakes in this area are about as common as Democrats in statewide offices.

Resources, news coverage:

• “Two small earthquakes,” Fort Worth Star-Telegram
• “Earthquakes rattle area,” Dallas Morning News
• Associated Press on November 1, “Rare aftershocks persist in North Texas”

Historically, Texas has not been a hotbed of earthquake activity, between 1973 and 2012.  Texas Seismicity Map from USGS.

Texas Seismicity, 1973-2012. USGS