1. LEG 162: NEW FRONTIERS ON PAST CLIMATES1

• Main Authors: Eystein Jansen, Maureen E. Raymo
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Nordic Seas; North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.469.1288; http://www-odp.tamu.edu/publications/162_IR/VOLUME/CHAPTERS/ir162_01.pdf

The North Atlantic Ocean and Nordic Seas represent one of the most climatically variable and sensitive regions on Earth. Our goal on Leg 162 was to recover sedimentary sequences with which to investigate the evolution of Northern Hemisphere climate on time scales ranging from hundreds to millions of years. These objectives required drilling rapidly deposited (>50 m/ m.y.) sequences, with triple APC coring to refusal. This approach allowed the retrieval of continuous sedimentary records for high-resolution analysis of the high frequency (orbital- and millennial-scale) components of the climate system. At the same time, these sequences also span the last few millions of years, an interval over which the average climate state has evolved toward generally colder conditions and over which the spectral character of orbital-scale variations has changed dramatically. Composite sections documenting continuous sedimentation were recovered at almost every site. These composites, many of which have sedimentation rates of over 10 cm/k.y., are based on continuous and high-resolution discrete data obtained by the multisensor track (including magnetic susceptibility, natural gamma radiation, P-wave velocity, and GRAPE bulk density), as well as spectral reflectance measurements. This data typically has a temporal resolution of hundreds rather than thousands of years. These sites will provide the basis of ultra-high-resolution paleoceanographic studies of a key region in the global climate system for years to come.