Available online
Description
The programme examines the nature of the compression pulses (P-waves) and transverse pulses (S-waves) which are generated by earthquakes and how these waves are used to study the internal structure... of the earth.
The programme examines the nature of the compression pulses (P-waves) and transverse pulses (S-waves) which are generated by earthquakes and how these waves are used to study the internal structure... of the earth.
| Module code and title: | S101, Science: a foundation course |
|---|---|
| Item code: | S101; 04 |
| First transmission date: | 13-03-1979 |
| Published: | 1979 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:24:00 |
| + Show more... | |
| Producer: | Patricia McCurry |
| Contributors: | Ian Gass; Mike Pentz; Geoff Brown |
| Publisher: | BBC Open University |
| Keyword(s): | Earth; Earthquakes; Royal Observatory, Edinburgh; Seismology |
| Footage description: | Colour still shots of the earth from space. Ian Gass, in the studio, introduces the programme. He points to a large disc, which represents a cut-away model of the earth, to how thin the crust is and how little of the earth's interior we have direct knowledge of. Film of a volcano and still shots of mineral samples thrown up by volcanoes. Short film of an earthquake in Japan. Aerial shots of the San Andreas fault in California. Ian Gass performs an experiment to demonstrate that earthquakes occur along fault lines. He uses a model of a section of the San Andreas fault for his demonstration. An animated diagram shows how vibrations from earthquakes propagate through the earth similar to ripples in water. Mike Pentz, using ball and spring models, demonstrates the properties if the p-waves and s-waves from earthquakes. He shows first how the waves propagate separately and then how they do so together. Brief film shots of Edinburgh and the Royal Observatory there. Inside one of the laboratories at the Royal Observatory, Geoff Brown examines some of the equipment which is used to monitor earthquakes. He points out particularly the seismometer and explains how it works. Brown goes on to examine a pen recording of an earthquake which took place in Stuttgart, Germany September 3rd 1978. He explains how the direction and distance of the earthquake are determined from this data. Ian Gass, with the aid of animated diagrams, explains how the information provided by P and S waves is used to determine some of the properties of the earth's interior. The animations show the mantle, the core and an inner core. Over shots of meteor fragments and mineral rocks made of the sorts of materials found in the mantle and crust, Gass explains how a knowledge of the physical properties of the various layers of the earth can also tell something about their composition. |
| Master spool number: | 6HT/72879 |
| Production number: | 00525_1334 |
| Videofinder number: | 1179 |
| Available to public: | no |
