Available online
Description
The programme follows the river Glaslyn from its source near Snowdon to its mouth in the Portmadoc estuary. The process of weathering, erosion, transportation and deposition at various stages along... its course are examined.
The programme follows the river Glaslyn from its source near Snowdon to its mouth in the Portmadoc estuary. The process of weathering, erosion, transportation and deposition at various stages along... its course are examined.
| Module code and title: | S101, Science: a foundation course |
|---|---|
| Item code: | S101; 26 |
| First transmission date: | 04-09-1979 |
| Published: | 1979 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:24:00 |
| + Show more... | |
| Director: | Patricia McCurry |
| Contributor: | John Wright |
| Publisher: | BBC Open University |
| Keyword(s): | Glaslyn |
| Subject terms: | Erosion; Rivers; Sedimentation and deposition; Geomorphology; Rivers; Sedimentation and deposition |
| Footage description: | Aerial and ground film shots of the Portmadoc estuary. Commentary by John Wright introduces the programme. Aerial film shots of Snowdon. Commentary by Wright explains how the topography here was by glacial actions. He goes on to explain what processes of active erosion take place here now. Shots of Glaslyn lake, source of the river Glaslyn just below the summit of Snowdon. Shots of the river below the lake. Wright points out the various rocks which make up the stream bed at this point and also explains how these are transported down river in the spring thaws. Wright briefly looks at a tributary stream to the Glaslyn and then comments on 'the enormous power of the glaciers which cut out this valley. Aerial shots of a lake fed by the Glaslyn a little further downstream. Wright points to the sediments from the river which are silting up the lake. At another lake a little further downstream, Wright examines the sediments which have been deposited here by the river. He points out how the force of the river flow affects the sorting of sediments at this point. Wright looks at the river Glaslyn further downstream at a point where it is met by a sizeable tributary. He points out the various forms the flow of water takes in this area and also what the implications for this are on sediment deposit. Wright examines some of the sediments. Also shots of a histogram which sorts the sediments by grain size while he talks. Film shots, both aerial and from the ground, of the lower reaches of the river Glaslyn. Wright looks at the sediments on the flood plane there. A histogram shows the distribution of grain size. Wright goes on to look at some stratified sediment on the flood plain and points out that this area is an example of sedimentary rock in the making. He then looks at the sands which make up the estuary down to the very finest found in the harbour at Portmadoc. Wright, standing on the estuary sands, sums up the programme. |
| Master spool number: | OU3135 |
| Production number: | FOUS026X |
| Videofinder number: | 1201 |
| Available to public: | no |
