Benjamin S. Slotnick (a), Gerald R. Dickens (a), Chris J. Hollis (b), James S. Crampton (b), C. Percy Strong (b) & James C. Zachos (c)
(a) Department of Earth Sciences, Rice University, Houston, TX 77005, USA. E-mail: bss2@rice.edu
(b) GNS Science, Lower Hutt, New Zealand
(c) Earth and Planetary Sciences Department, University of California, Santa Cruz, CA, USA.