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Description
This programme is about models to explain the formation of oceanic crust and the kind of evidence geophysicists look for to support these models. The programme begins with Dr. Eldridge Moores recal...ling the petrology of the rocks on Troodos. He shows how the sequence is less well defined that that suggested by the Greenbaum model which has been discussed in a previous programme. Professor Ian Gass continues by discussing other aspects of the geology of Troodos. He reminds the student of his ideas of how Troodos formed before handing over to Eldridge Moores again who holds a different view. Eldridge Moores discusses the world wide occurrence of ophiolite complexes and presents a subduction mechanism to account for the sequence of oceanic crust and ophiolite complex seen in Cyprus. The programme takes a different turn by Ian Gass pointing out that part of the problem of understanding the formation of oceanic crust is to understand first why continental crust breaks apart where it does. He suggests that an ideal place where this process can be studied is the Red Sea. Dr. Richard Whitmarsh presents a considerable amount of evidence to show that sea floor spreading is taking place in the Red Sea, and suggests that when the African and Asian continents began to move apart; 22 million years ago, perhaps the African rift valley extended as far north as the Mediterranean Sea. Ian Gass takes up the story by suggesting what happened in this region to cause continental drift and the formation of new ocean floor.
This programme is about models to explain the formation of oceanic crust and the kind of evidence geophysicists look for to support these models. The programme begins with Dr. Eldridge Moores recal...ling the petrology of the rocks on Troodos. He shows how the sequence is less well defined that that suggested by the Greenbaum model which has been discussed in a previous programme. Professor Ian Gass continues by discussing other aspects of the geology of Troodos. He reminds the student of his ideas of how Troodos formed before handing over to Eldridge Moores again who holds a different view. Eldridge Moores discusses the world wide occurrence of ophiolite complexes and presents a subduction mechanism to account for the sequence of oceanic crust and ophiolite complex seen in Cyprus. The programme takes a different turn by Ian Gass pointing out that part of the problem of understanding the formation of oceanic crust is to understand first why continental crust breaks apart where it does. He suggests that an ideal place where this process can be studied is the Red Sea. Dr. Richard Whitmarsh presents a considerable amount of evidence to show that sea floor spreading is taking place in the Red Sea, and suggests that when the African and Asian continents began to move apart; 22 million years ago, perhaps the African rift valley extended as far north as the Mediterranean Sea. Ian Gass takes up the story by suggesting what happened in this region to cause continental drift and the formation of new ocean floor.
| Item code: | S2-4; 04 |
|---|---|
| First transmission date: | 02-09-1973 |
| Published: | 1973 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:24:11 |
| + Show more... | |
| Producers: | Andrew Crilly; David Jackson; Barrie Whatley |
| Contributors: | Ian Gass; Eldridge Moores; Paul Vaughan; Robert Whitmarsh |
| Publisher: | BBC Open University |
| Keyword(s): | Continental crust breakdown; Models; Oceanic crust formation; Ophiolite complexes; Plate tectonics; Red Sea; Subduction mechanism; Troodos rocks petrology |
| Footage description: | Paul Vaughan introduces the programme. He introduces Prof. Eldridge Moores. Eldridge Moores discusses the petrology of the Troodos complex with the aid of a model to support the sea floor spreading hypothesis. Moores with further models which show the rock sequence as found on Troodos and model of the sea floor spreading phenomenum. Ian Gass with a model of Cyprus discusses other aspects of the geology of Troodos to support the sea floor spreading hypothesis. He then introduces Moores again who discusses his hypothesis of the origins of Troodos. Moores points out that there are ophiolite complexes similar to Troodos in other parts of the world and points these out on a map. He then explains his hypothesis of the origins of Troodos with the aid of animated diagrams. Moores discusses the history of the plate tectonic processes as found in the evidence of the ophiolite complexes. Gass with a geologic map of the world showing the various sea floor spreading ridges. He points out that a major part of the problem of understanding how oceanic crust forms is to understand why continental crusts break apart to form oceans. He suggests the Red Sea as an ideal place to study this process. Shots of photographs taken by satellite of various parts of the Red Sea. Robert Whitmarsh presents a considerable amount of evidence to show that the Red Sea is a young ocean and that sea floor spreading is taking place there. He uses several maps and diagrams to aid his discussion. Paul Vaughan continues the discussion on sea floor spreading in the Red Sea. He too uses animated diagrams to aid his discussion. Commentary to the diagrams is by Whitmarsh. Seismic techniques for gathering the evidence are explained. Whitmarsh continues his discussion on the evidence for sea floor spreading and continental break in the Red Sea. He uses maps to aid his discussion. Ian Gass presents a model which gives his view of geologic events in the Red Sea area over the past 22 million years. Several diagrams, some animated, aid his discussion. |
| Master spool number: | 6HT/70964 |
| Production number: | 00525_1016 |
| Videofinder number: | 671 |
| Available to public: | no |
