Thus far, ODP Leg 171B has had its largest scientific impact in producing some of our most detailed records to date of events associated with Cretaceous black shale events, the North Atlantic history of the Cretaceous–Paleogene impact, and our first detailed chronologies of the Paleocene/Eocene boundary. The drilling leg also proved that it is possible to recover expanded sequences of quite old sediments at shallow burial depth and served to usher in a renewed interest by paleoceanographers in the climatology, evolution and oceanography of past "extreme" climates. Continued work on the middle and upper Eocene strata drilled during Leg 171B will provide fresh insight into the climate variability and chronology of the transitional period between the Eocene greenhouse world and the glaciated Earth of the Oligocene and Neogene.
The JOIDES "extreme" Climates Program Planning Group has recently formulated a rationale for drilling records of past extreme climates. (Kroon et al., 2000b). Many of the phenomena such as those found at Blake Nose can be modeled to test aspects of Earth’s climate, the carbon cycle, and marine ecosystems. The geochemical aspects of the transient, large disturbances associated with greenhouse gases can be revealed in sediments, as shown by Blake Nose drilling. It is now of the utmost importance to drill and recover sediments from the same events, which are characterized by large perturbations of the carbon cycle in other parts of the world along depth transects. Documentation of the amplitude and timing of change of these events will increase understanding of the pervasiveness of the events and the processes involved.