Forams for Correlation

On a previous web page Foram Evolution, we discussed how scientists have painstakingly pieced together the geologic time period and preferred environment for many individual foram species. This knowledge is applied every day by geologists all over the world to solve practical, real-world problems.

What do we mean by correlation? Correlation means connecting two different things in some way. Geologists might "correlate" rock samples from two different locations because they have the same age. Those rocks would be "age correlated". Let's go a step further and say the rocks are the same age and they were deposited at the same water depth. Then they would be correlated by age and depth.

Let's look at two examples where forams are routinely used for correlation - the Ocean Drilling Program and the petroleum industry.

Integrated Ocean Drilling Program research vessel in Bermuda (Credit: Integrated Ocean Drilling Program, http://www-odp.tamu.edu/public/life/index.html)
Offshore drilling rig in the US Gulf of Mexico (Credit: Stephen C. Shaffer, Minerals Management Service, US Department of the Interior)