Teaching applied biostratigraphy and sea level variations: A geoscience education experiment

Fossils are the key to dating the past, but geoscience students are rarely exposed to their use in constraining geologic time and deciphering regional sediment history. A software package and an associated student exercise that uses real data sets of fossils and sediment trends from drill sites in the Gulf of Mexico is developed to illustrate the application of biostratigraphy to understand regional depositional history and sea-level variations. TimeScaleCreator Crossplot, a visualization system to understand the depth-to-age conversion methodology for converting well datasets varying in depth to geologic timescale was developed and tested. A transect consisting of four offshore wells and two onshore wells spanning Miocene and Oligocene epochs along an approximate linear trend was chosen to illustrate the concepts of sea-level variations. Depth-to-age conversion routine enables the students to convert the accompanying sediment facies to geologic timescale by comparing the fossil assemblages observed in the well to the biostratigraphy of Gulf of Mexico. After creating a transect from depth-to-age converted wells, students can identify depositional episodes of sand-dominated influxes separated by shale-deposition. The interplay between various sand and shale sequences allows the students to interpret sea-level variations in the northern Gulf of Mexico basin. The student exercise developed consists of an introduction to biostratigraphy, depositional history in the Gulf of Mexico basin and a manual on how to use the visualization tool, which serves as background material to convert the wells from depth-to-age and interpret for sea-level variations. The student exercise is tested with undergraduate students and evidence of student learning is discussed. The student exercise also contains a teacher\u27s manual that provides our suggested solutions