Available online
Description
The programme shows several lines of evidence which are used to build up a picture of the various climatic conditions which existed in Britain in the geological past. The programme is introduced an...d linked by Professor Ian Gass. The other speakers are Dr. Chris Wilson and Dr. Dennis Jackson, Senior Lecturers in Earth Sciences at the Open University, and Eric Skipsey, Regional Science Tutor for North-East England. The evidence for climatic conditions includes dreikanter pebbles from the British Trias, oxygen isotope work on the cross-section of a Jurassic belemnite from Skye, Hate Precambrian boulder beds from the island of Islay, the Carboniferous tree remains in the Fossil Grove at Victoria Park in Glasgow, wind blown desert sands in the Permo-Triassic rocks seen on the coastal cliffs of South Devon, and the fossil assemblage including the seeds of the Nipa Palm, found in the London clay in south-east England.
The programme shows several lines of evidence which are used to build up a picture of the various climatic conditions which existed in Britain in the geological past. The programme is introduced an...d linked by Professor Ian Gass. The other speakers are Dr. Chris Wilson and Dr. Dennis Jackson, Senior Lecturers in Earth Sciences at the Open University, and Eric Skipsey, Regional Science Tutor for North-East England. The evidence for climatic conditions includes dreikanter pebbles from the British Trias, oxygen isotope work on the cross-section of a Jurassic belemnite from Skye, Hate Precambrian boulder beds from the island of Islay, the Carboniferous tree remains in the Fossil Grove at Victoria Park in Glasgow, wind blown desert sands in the Permo-Triassic rocks seen on the coastal cliffs of South Devon, and the fossil assemblage including the seeds of the Nipa Palm, found in the London clay in south-east England.
| Item code: | S23-; 11 |
|---|---|
| First transmission date: | 17-06-1972 |
| Published: | 1972 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:24:22 |
| + Show more... | |
| Producer: | Peter Clarke |
| Contributors: | Ian Gass; E.(Eric) Skipsey |
| Publisher: | BBC Open University |
| Keyword(s): | Carboniferous tree remains; Climatic conditions; Dreikanter pebbles; Fossil grove; Geological past; Jurassic belemnite; Lines of evidence; Permo-Triassic rocks; Precambrian boulder beds; Skye |
| Footage description: | Ian Gass with two Dreikanter specimen. One is from British Triassic sandstone, the other from present day Saudi Arabia. Gass deduces from this that the climate in Britain 230 million years ago was arid desert. Gass next explains a method of determining water temperatures in the past by recording variations in calcite of certain fossil skeletons. These are due to the ratio of isotopes which vary with temperature. Gass uses a thin section and graph to aid. Shots of a late pre-Cambrian metamorphosed sediment in Argyleshire. Gass with a large specimen of this rock (a Tillite) in the studio. He points out the boulder debris in the sediment and concludes that it must have been due to glaciation and that late pre-Cambrian Britain was experiencing glacial conditions. Shots of Eric Skipsey in Victoria Park, Glasgow. He enters a large green house which contains fossilized plants from the Carboniferous period (mainly Giant Club Masses, Lepidodendron). Skipsey explains that these were tropical swamp trees and that the Carboniferous climate must therefore have been wet and tropical. Shots of several other Carboniferous plant fossils. Gass with a map of tho world showing areas which were experiencing hot, equatorial climates during the Carboniferous. He point out the areas which were affected by glaciation during the same period. Chris Wilson at Torbay explains that very arid conditions prevailed there 250 million years ago during the New Red Sandstone period (Triassic/Permian). He examines 2 sites for evidence of these conditions. At one site, Wilson works out the wind direction at the time of the sedimentary deposition. He then sums up the environment of the area at the time. Gass with a map of Britain which had marked on it the prevailing wind conditions during this period as worked out from several sites. Aerial shot of London showing St. Paul's and surrounds. Shots of foundations being dug in the clay for a building. Dennis Jackson examines the clay. He digs out a shark tooth and other Eocene fossils. (Crocodiles, turtles, nautilus) Jackson next examines the fossil seed of Nipa, a stem-less palm. He then speculates on the sort of climate that could bring all these fossils together in the London clay. Film shots of Jackson in the Geological Museum, London. He examines an artist's impression of the landscape of Southern England during the Eocene. Gass compares the Eocene fossil Nipa seed with a modern one found only on the Malayan archipelago. He deduces from this that the climate has generally deteriorated since the Eocene. Gass sums up. |
| Master spool number: | 6HT/70599 |
| Production number: | 00522_3113 |
| Videofinder number: | 1719 |
| Available to public: | no |
