Prehistory

The Distant Past

As one looks back across time to the distant past, evidence of such times becomes difficult to find. Fossils and other remnants are lost or broken beyond recognition. Only the most durable survive, and the geological record is perhaps the best source of information of the very distant past.

Restoration Park, as part of Louisiana, has a long and complex geologic history. For a large portion of the Earth's 4.6 billion years of existence, Restoration Park and the rest of what is now Louisiana were covered by the seas for billions of years. Only recently in the geologic history of the Earth has Restoration Park been emergent or a part of the land.

During a geologic period known as the Tertiary, which began approximately 66 million years ago with the extinction of the dinosaurs, Louisiana began emerging from the oceans. For the next 30 to 40 million years, Louisiana fluctuated from deltas and lowland swampy environments to shallow marine seas flooding the land. By the end of the Tertiary Period, Louisiana finally emerged as land. Consequently, the surface exposures at Restoration Park are quite young geologically. Whereas some parts of North America may have exposures that hundreds of millions or even billions of years old, the surface sediments in Louisiana are mainly less than 50 million years old.

Over the last two million years during a time known as the Pleistocene Epoch, massive sheets of ice known as glaciers extended for thousands of square miles covering most of Canada and the northern United States. These Pleistocene glaciers had a tremendous effect upon North America by scouring the land and reshaping the landscape. The tremendous erosive power of these glaciers carved the Great Lakes between Canada and the United States. The glaciers advanced and retreated numerous times. Whenever they retreated, huge volumes of ice melted forming thousands of rivers and streams that carried gravel, sand, and silt southward toward the Gulf of Mexico. As the rivers crossed Louisiana, some sediment was deposited forming extensive layers of sand and gravel. Deposits of these types were common in Ouachita Parish, and one thick deposit formed at the site of Restoration Park. Thousands of years later, this sand and gravel deposit was extracted forming the depression now present at Restoration Park.

Evidence of the Pleistocene gravels and sands from the melting of the glaciers can still be found in many places in Restoration Park, especially along the creek and the sides of the old quarry. The sides of the old quarry can be easily detected as steep areas common along the crushed rock walking trails. The gravels, which were eroded from the northern part of the United States, were transported by the glacial meltwater rivers to Restoration Park. Many of the pieces of gravel contain fossils of ancient sea life since the eroded rocks were once part of the sea bottom in the northern United States hundreds of millions of years ago. Although the gravels were transported to Louisiana only in the last two million years, the parent rock is Paleozoic in age.