{"id":8,"date":"2019-07-02T10:40:08","date_gmt":"2019-07-02T14:40:08","guid":{"rendered":"http:\/\/www.personal-site.dev\/?page_id=8"},"modified":"2019-11-23T09:30:54","modified_gmt":"2019-11-23T13:30:54","slug":"front-page","status":"publish","type":"page","link":"https:\/\/www2.whoi.edu\/site\/longcore\/","title":{"rendered":"Homepage – Simple with slider"},"content":{"rendered":"\n\t

Introduction<\/h1>\n\t\t\t\t\n\t\t\t\t\"Knorr\"\n\t\t\t\t<\/a>\n\t\t(Photo by Alexander Dorsk, Woods Hole Oceanographic Institution)\n\t

In 1999 Woods Hole Oceanographic Institution began the development of a new long coring system for the UNOLS vessel RV\u00a0Knorr<\/i>. Long coring, a hallmark of marine geology research in the 1970s, had been abandoned in the United States since about the mid 1980s. Yet the need for high quality long cores did not diminish. The French system on the\u00a0Marion Dufresne<\/i>\u00a0Antarctic supply vessel, called the Calypso Core, had proven its coring capabilities throughout the 1990s by collecting extremely long piston cores in many very important locations.

Reestablishing long coring on UNOLS vessels, however, is not an easy task. Previous long coring operations on RV\u00a0Knorr<\/i>\u00a0suffered because the vessel is not so long itself (85 meters compared to 120.5 meters for\u00a0Marion Dufresne<\/i>). In addition the winch and other handling equipment were not strong enough to withstand the increased pullout tensions experienced by 40 and 50 m cores.\u00a0 As a result all previous Giant Piston Cores were lost due to wire parting.

To overcome these obstacles, WHOI hired the marine architectural firm Glosten Associates to determine what it would take to allow\u00a0Knorr<\/i>\u00a0to successfully recover 50 m cores with extremely high pullouts (up to an extreme case of 80,000 lbs). Based on models of\u00a0Knorr’s<\/i>\u00a0stability, starboard side pullouts proved to be unsafe, but pullouts from the centerline of the stern could be safely handled up to 160 tons.

Since it is not easy or prudent to deploy a 50 m core over the stern, we developed a conceptual design for coring on\u00a0Knorr<\/i>\u00a0that includes starboard side lowering to a vertical position, transfer of the core from the starboard side to the center line of the stern, coupling of the core to the release and winch systems, and lowering to the sea floor from the stern. An animation of the entire process can be accessed at the upper right corner of this page.<\/p>\n

Several major developments were involved with making this conceptual design a reality:<\/strong><\/p>\n