Ocean Survey Program (OSP) bathymetry history: Jousting with tectonic windmills

• Main Author: N. Christian Smoot
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2001
• Subjects: Pacific; Southern Ocean
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.596.1585; http://www.tags-21.info/Mission/Documents/Smoot_OSP_Bathymetry_History.pdf

Abstract: The plate-tectonic hypothesis in the ocean basins is difficult to defend. The hypothesis was formulated in the early 1960s when relatively little was known about the ocean floor, roughly 70 % of Earth's surface, and ocean floor mapping technology was still in its infancy. A small scattering of ship-of-opportunity sonar data did little to show anything other than a few megatrends, such as fracture zones and mid-ocean ridges. In 1974 an updated bathymetry set became available for the general public, but it was not incorporated into the working hypotheses. It showed, especially for the Pacific basin, trends going WSW--ENE, and trends going NNW--SSE. The data also showed mini-crosstrends passing WNW--ESE. These were result of hot-spot activity and were used to show seafloor spreading to the WNW. From 1967 to 1996 multibpam sonar data, called SASS, was collected by the US Navy for the submarine program. Pieces of this data were released, and many ONR contractors came to the Navy to use this data for various purposes. In 1989 a stick-figure tectonic diagram of the Atlantic Ocean basin was published, and it showed that the fracture swarm megatrends meander, braid, merge, splay, start, and stop any place and are generally aligned with, or contain, the linear seamount chains. Geophysical data collected by satellite altimetry, Seasat and GEOSAT, were determined to be the equivalent of bathymetry as far as structural trends were concerned, and this opened up the southern ocean basins to be included in any working hypotheses. When compared to the available bathymetry, this seemingly jumbled tectonic structure was verified. The hot-spot tracks were shown to be trans-basinal, so that three complete sets of trends cross the basin. This is a physical