Eight short cruises over the last 3 years, each of from 1 to 3 weeks’ duration in either R.V.
Sarsia
or R.R.S.
Discovery II
, were specially planned having regard to some of the geological and allied problems which could be expected in the Western Approaches leading out to the edge of the continental shelf, and hence to the upper parts of the continental slope. Fourteen scientists have so far participated in one or more of these cruises, mainly geologists and engineers. The primary geological objective is to try and arrive at an explanation of the origin of the continental slope, which will necessarily involve the origin of the adjacent continental shelf. To a geologist, the logical approach to the problems is, first, to determine the geological sequences in the shelf and, secondly, thus to extend the shallow structures and successions determined there to the upper reaches of the slope. The thin cover of a few inches of sand and gravel which normally occurs on the sea bed of the English Channel will almost certainly become too thick in a westerly direction for penetration by those coring methods which are at present available, and the most promising methods by means of which the established geology of the Western Approaches will be connected with the upper ranges of the continental slope are, first, the thumper and sparker techniques and, secondly, dredging from rock outcrops now known to occur on the slope. Such an orthodox geological approach demands progress
pari passu
from east to west. Our provisional results, of which progress reports follow, are thus mainly, but not entirely, concerned with the Western Approaches west of longitude 4° W.
West Florida Continental Shelf: a study of geothermal flows and other processes affecting radionuclides and trace metals. Progress report, October 1, 1979-July 1, 1980