Map Monday

The powerful story of our coastal evolution—one only geology can reveal.

Our beautiful Mississippi Gulf Coast is a testament to the power of Mother Nature through deep time. The story of its natural history can only be unlocked through geologic mapping. The new tools of detailed lidar data coupled with test hole drilling and the study of fossils & outcrops helps our MDEQ’s State Geological Survey scientists tell the ancient story of our state’s coastal region.

The most influential part of this story can be found in the last few chapters of Earth’s history, recorded in the geology exposed at and near the surface. Our coastal region was largely shaped during the Pleistocene epoch, going back some 2.58 million years ago. During this time in earth’s history, sea levels rose and fell drastically due to cyclic glaciation. This left behind broad, coast-parallel terraces that were created during warm interglacial marine high-stands. Streams carved their valleys deep into the coastal plain as sea levels fell during the colder glacial episodes. The last glacial cycle ended some 11,700 years ago, as the last of the continental ice sheets melted. Sea levels finally rose to the coastline that we see today, only some 5,000 to 8,000 years ago.

We are proud to announce the release this week of a new publication by our State Survey scientists, the beautifully-detailed geologic map of our Mississippi coastal counties. This important project was funded by a cooperative grant with the USGS’s State Map geologic mapping program. It is a greatly updated interpretation of our coastal geology, depicted with detailed LiDAR, accompanying cross-sections, and unit descriptions. This map will provide an improved baseline for the understanding of the geologic framework of Mississippi’s amazing coastal region.

Hard copies of this publication are available for order through our MDEQ, Mississippi Office of Geology publications and map sales department and available for free download here.