Six sites were drilled on the southern Iberia Abyssal Plain during Ocean Drilling Program (ODP) Leg 173. Three holes (1067A, 1068A, and 1069A) recovered Eocene sediments consisting of thinly bedded turbidite deposits with interbedded hemipelagic sediments (Bouma sequence Te) deposited near the calcite compensation depth. The hemipelagic sediments are barren of nannofossils, necessitating the use of the turbidite deposits to erect an Eocene biostratigraphy for these holes. Moderately preserved, diverse assemblages of nannofossils were recovered from silty clays (Bouma sequence Td) and poorly preserved, less diverse assemblages were recovered from sandy/silty clays (Bouma sequence Tc). Hole 1067A has a continuous record of sedimentation (Subzones CP9a-CP14a) and Holes 1068A and 1069A have similar continuous records (Subzones CP9a-CP12a), although all holes contain barren intervals. Holes 1067A, 1068A, 1069A, 900A (ODP Leg 149), and 398D (Deep Sea Drilling Project Leg 47B) display a similar increase in mass accumulation rates in the lowermost middle Eocene. A reliable Eocene biostratigraphy has been erected using nannofossil data from turbidite sequences, allowing for correlation between Iberia Abyssal Plain sites.
1McGonigal, K.L., and Wise, S.W., Jr., 2001. Eocene calcareous nannofossil biostratigraphy and sediment accumulation of turbidite sequences on the Iberia Abyssal Plain, ODP Sites 1067-1069. In Beslier, M.-O., Whitmarsh, R.B., Wallace, P.J., and Girardeau, J. (Eds.), Proc. ODP, Sci. Results, 173 [Online]. Available from World Wide Web: <http://www-odp.tamu.edu/publications/173_SR/chap_04/chap_04.htm>. [Cited YYYY-MM-DD]
2Department of Geological Sciences, Florida State University, Tallahassee FL 32306, USA. Correspondence author: roessig@gly.fsu.edu
Initial
receipt: 20 October 1999
Acceptance: 30 August 2000
Web publication: 30 April 2001
Ms 173SR-008