http://www.beg.utexas.edu/UTopia/images/pagesizemaps/tectonic.pdf
The fault line that runs virtually up I-35 between San Antonio and Dallas-Fort Worth (Balcones Fault Zone) has been inactive for quite some time, a considerable amount of time, so much so, that most people living there do not even know it exists. That is unfortunate, because what people do not know can hurt them. Think of the San Andreas fault line. It is 9-12 miles deep and about 6 miles wide. Most of the 9-12 mile depth is below ground, and therefore, not visible. You will, however, see a hole that could be 9-12 feet deep by about 6 feet wide, running the entire gamut of the fault. Ground continually rebuilds itself if left unmolested for a certain length of time, depending on climate. Point being, when compared to the inactive I-35 fault line, the San Andreas is visible from above ground. The Balcones Fault Zone itself is not really visible from above ground. Well, there are exceptions, striking ones. Email downsouthman1@yahoo.com for more info. If you are not familiar with the topography around Killeen, TX, let me fill you in. There exists s a large area, about 30 visible feet wide and 10-15 visible feet deep that runs from virtually, visible within range from US-190 traveling west looking south just as you pass The Rosewood Retirement Community (on the left). It travels south for a longer distance than I have tried to get on peoples private property to see. Especially in TX, where people can legally kill you just for being on their property. Back to the point, that is a fault zone that the ground still hasn't completely grown over. That shows how relatively recent this fault has been active, in the grand scheme of things.
In The DFW Metroplex, companies currently drill for natural gas, but not in the way that you would expect. They come up to your house and say, 'Hey, we'll pay you $300 a month if you let us drill below your house for an alternative to fossil fuels. It doesn't harm the land or environment at all.' Who would not fall for that? Who cannot use $300 a month right now, in this economy? Here is the problem with that. During the time that the Balcones Fault Zone has been inactive, for the most part the ground grew over the fault, thus the gases still having been released by the gaping hole in the earth miles below, were essentially trapped and have been for some time now. There are scattered pockets of natural gas throughout the fault zone, including the DFW Metroplex. When these gases are extracted, due to the drilling process, it dramatically increases the instability of the ground from the surface level, all the way down through part of the mantle, approximately 12 miles deep. This occurs because as those pockets of pressurized gas, which essentially hold the ground together, are released, the pressure in the ground reduces, making it unstable. Then there are massive holes in the rock under the surface that are not really being held together by anything and gravity is working against it. Eventually parts of rock will fall. If large pieces of rock fall, this will cause earthquakes, like the recent ones that have been reported in the Metroplex. As more earthquakes continue, the fault is slowly coming back to life. In other words, what I am saying is that our quest to find clean energy is reactivating the Balcones Fault Zone. It is only a matter of time before large quakes plague the I-35 corridor from San Antonio to DFW, and all cities in between.
I briefly want to throw in that Flash Flood Alley also exists along the same general area as the Balcones Fault Zone, I-35, from roughly San Antonio to DFW. It also has something to do with this, as I will explain right now. If you look at topographical maps of the area we have been discussing, the elevation increases pretty noticeably from genearlly 0-25 miles east of I-35, traveling east compared to generally 0-25 miles west of I-35, traveling west. If you just travel north or south on I-35, you will not notice what I am referring to, but if you travel west or east on US-190, even in as short of a distance as Temple to Copperas Cove, you will definetely see what I mean. This short 30-45 minute drive has a plethora of geological features. Not only geographical features but also changes in elevation. Nothing super signifant, just signs of previous tectonic plate and fault activity. Any other highway that crosses I-35 east or west generally shows the same basic features. Thanks for reading. Please provide feedback as this is a work in progress.
Email downsouthman1@yahoo.com if you would be so inclined towards discussing this.
Update 1-19-2015: Construction around the area that I described in Killeen has made this difficult to observe from the highway.
Update 1-19-2015: Construction around the area that I described in Killeen has made this difficult to observe from the highway.
