Brief Review of Exploration of the Mid-Atlantic Ridge Near Latitude 45°N, and Partly Annotated Bibliography of the Study Area, 1960-1975
The continuity and morphological significance of the Mid-Ocean Ridge system was recognized by the late 1950s. The global reconnaissance cruises had established its main characteristics throughout the world oceans, and a number of questions were asked regarding the structure composition and the tectonic setting of the ridge. It was gradually realized that to answer these questions, concentrated and detailed examination of the ridge should be earned out over carefully selected segments.
In August 1960s under the scientific leadership of M. N. Hill, a Cambridge University scientific party on board RRS Discovery II, examined a blockage of the median valley near lat 45°50’N and thus initiated the study that.eventually engaged a total of over 12 months of ship time during nine different cruises. The listing of these cruises is given in Table 1.
An area selected for a detailed study should be representative of the general characteristics of the 'ridge. 11iis was the main criterion for selecting the Mid-Atlantic Ridge nearlat 45N On the basis of-information available in tbe early 1960s. it was believed that the ridge at lat 45N was fully developed. that it was not interrupted by fracture zones. and that its seismicity was not unusual.The study area was about midway between Charlie~Gibbs Fracture Zone (at 52N) and the Azores (37N) and was sufficiently far south to benefit from the summer high pressure area (Azores high). giving it reasonably good working weather. As the study. progressed. the complexity of real geology became evident The simple and uniform models reflect
Figures & Tables
Edited by Peter A. Roma and published in 1976, Mid-Atlantic Ridge contains a collection of related articles reprinted from other Geological Society of America publications as well as a brief review of exploration of the Mid-Atlantic Ridge from 1960 to 1975.