Blog Entry 2

The landscape of New Orleans is one of a kind.  New Orleans contains a large portion of wetlands and has a marshy climate.  One concern that many share for New Orleans is that it is sinking.  About 49% of New Orleans is below sea level and it’s soil, made up of soft sediment, allows for it to continue to sink deeper.

While many have blamed oil drilling or the nature of the ground for the sinking, another hypothesis is that tectonic plates cause the sinking.  The Michoud fault goes through eastern New Orleans and boasts some of the highest subsidence (the sinking of land) rates in the region.  The fault line occurs where much of the ground is made up of shale and salt, which are fairly unstable.  While tectonic movement may be responsible for a good deal of sinking, the elevation of New Orleans and constant flooding causes the soil is also draining while some of the sediments are being forced together causing compression to occur, making more room under New Orleans for sinking to occur.

Sinking and flooding are responsible for the geographical features of New Orleans.  There are marshes and swamps where water has enveloped the land and in areas where land has completely sunk below water there are lakes and bayous, which are partially responsible for the humid climate.

This sinking is having drastic effects on the people of New Orleans.  The decreasing elevation of New Orleans makes it so that populated areas are becoming more and more susceptible to floods, and the dams and levees that were built to protect the city are being rendered ineffective by subsidence.  Not too long ago, we saw the people of New Orleans devastated by Hurricane Katrina.  As New Orleans continues to sink, floods will destroy homes and lives.

Sources:

http://www.buzzle.com/articles/geography-of-new-orleans.html

http://www.washingtonpost.com/wp-dyn/content/article/2006/04/02/AR2006040201009.html

http://en.wikipedia.org/wiki/Michoud_fault