Stratigraphy is a geologic term defined as "The science of rock strata." Basically, it means looking at how sediments are deposited, and interpreting the conditions under which these rocks formed. In the case of Lozier Pond at Hyde Park, New York, these sediments are still sediments, and have not yet been transformed into rock. Simply put, by looking at the changes in the sediments over time in the bottom of the pond, many questions about the changes that took place to the pond over time can be answered, such as "Did the water depth change over time?" or "When did the lake change into a swamp, and why?"

For more detailed information on the stratigraphy of Lozier Pond:

Map of Lozier Pond, with locations of stratigraphic analyses
General stratigraphic description of units observed in the Lozier Pond
Stratigraphy of Trench 3
Photos of Trench 3
Stratigraphy of Trench HPM-2
Photos of Trench HPM-2
Stratigraphy of Core LP2A