Located in a flat marshy land mass, extensive drainage had to be built to accommodate the city of Houston. The adjoining prairie land simply drains into the flood-prone city. Houston’s surface is comprised of clay, shale, and very poorly cemented sand that is many miles deep in some areas.
Developed of river deposits that were formed of the erosion that came down from the Rockies, the sediments comprised of organic marine matter that had decayed over the course of time, and would be transformed to oil and even natural gas.
Under the many layers of sediment, water that was deposited over halite, which is a rock salt, sits patiently waiting for the next flood. These porous layers were slowly forced upward and the salt created dome formations that would trap the oil and the gas which would seep out of the porous sand.
This thick oil would seep out and occasionally, show as a black surface soil that is ideal for rice farming on the outskirts of the city that continues to grow to this day. While renowned for the hurricane’s that sweep through the region in hurricane season, Houston also has over 150 faults that are still active to this day. While there haven’t been any significant earthquakes in the region, researchers are still concerned that it could easily happen given time. No recorded events of earthquakes have come to light, but it is definitely a possibility that cannot be discounted.
Many areas are sinking due to the water table and the fact that the water is being pumped out of the ground at a constant rate. This also may be related to the faults and as they slowly evolve the slipping ground may be having smaller sized earthquakes that simply haven’t been detected. stationary faults frequently slip enough to cause a seismic wave.
However, when they’re “creeping” in lieu of sudden movement, it’s not as readily noted. This creeping can further reduce the chance of earthquakes as the land mass is slowly in motion but there aren’t any sudden violent movements like the other earthquake-prone regions experience.
The region enjoys plenty of activity and is a seismic wonderland for scientists who are monitoring the area and recording their research. Most residents of Houston have absolutely no idea that the region is lying on fault lines that could give way to a huge earthquake at some point in time.