9. AGE OF SUB-BOTTOM SULFIDE SAMPLES AT THE TAG ACTIVE MOUND¹

Claude Lalou,² Jean Louis Reyss,² and Evelyne Brichet²

  ABSTRACT

Eight sulfide samples from eight cores from Trans-Atlantic Geotraverse (TAG) drilling areas 1, 2, 4, and 5 (ODP Leg 158) have been age dated using ²¹⁰Pb/Pb and ²³⁰Th/²³⁴U methods. In spite of the low number of samples, they give a comprehensible scheme of the possible evolution of the TAG active mound from 20 ka to the present. In conjunction with previous geochronological results obtained from samples dredged or collected by the Alvin submersible research vehicle, a hypothesis for the development of this structure during the last 50 ka is proposed.

¹Herzig, P.M., Humphris, S.E., Miller, D.J., and Zierenberg, R.A. (Eds.), 1998. Proc. ODP, Sci. Results, 158: College Station, TX (Ocean Drilling Program).
²Centre des Faibles radioactivités, CNRS-CEA, Avenue de la Terrasse, 91198 Gif sur Yvette cedex, France. Lalou: lalou@cfr.cnrs-gif.fr