Summary: Eos,Vol. 85, No. 49, 7 December 2004
Ocean Drilling Program (ODP) Hole 1256D,
drilled 500 m into oceanic basement in the
Guatemala Basin,is the first hole prepared
with the infrastructure desirable for drilling a
moderately deep hole into the oceanic basement
(1.5­2 km).A second ocean drilling leg to
this site should finish the recovery of the first
complete section of upper oceanic crust from
lavas down through the dikes into the upper-
most gabbros.
Although Site 1256 has many advantageous
features for a program to drill to the mantle,
planning such an operation now would be
premature,due in part to lack of engineering
experience.In addition,there is significant sci-
entific knowledge to be gained from drilling to
depths of 1­3 km.Only through the character-
ization of the heterogeneity of the ocean
crust by moderate-depth drilling at this and

Source: Acton, Gary - Department of Geology, University of California, Davis

Collections: Geosciences