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Programme in three parts with titles 1) Naming rocks 2) Palaeontology 3) Geological maps.
Metadata describing this Open University video programme
Item code: S23-; 04
First transmission date: 04-03-1972
Published: 1972
Rights Statement:
Restrictions on use:
Duration: 00:23:04
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Producer: Jim Stevenson
Contributors: Ian Gass; David Jackson
Publisher: BBC Open University
Keyword(s): Boundary; Fossils; Frequency distribution diagram; Garnet mica schist; Granite; Hand specimen; Quartz; Syenites; Thin section micrograph; Volume proportion
Footage description: Part 1 has title "Naming Rocks" and is presented by Ian Gass. Ian Gass examines a garnet mica schist in the form of a hand specimen and as a section micrograph. He points out the characteristic features. Gass examines a granite specimen in the same way. Gass examines specimen of several different kinds of granite (microgranite, coarse grained granite, pegmatitic granite, porphyritic granite, graphic granite and orbicular granite). Gass uses a thin section granite micrograph to demonstrate how one estimates the volume proportion of quartz (or any other mineral) in rocks. He does the same for another specimen and finds that one contains much Iess quartz. Can they both bo called granites? Gass uses a frequency distribution diagram for quartz volume to explain the boundary between granites and syenites is drawn. Part 2 has title 'Palaeontology' and is presented by D.E. Jackson, he compares a leaf taken from a living plant with a fossil leaf 30 million years old. He uses the fossil specimen to demonstrate how fossils occur lying on bedding planes in stratified rocks. Jackson examines some recently living bivalves (Mya) and compares these specimen with a fossil specimen 'Glycimeris' from the tertiary period. Jackson shows & compares several coiled ammonite fossil shells (Cosmoceras). Jackson uses two specimen of the Jurassic bivalve Myophorella to demonstrate how the internal shapes of empty shells are preserved. Jackson with a fossil specimen of part of a Jurassic tree. He explains how groundwater preserved this specimen. Jackson with a fossil salamander from the Miocene. He then shows fossil foot prints of a salamander like creature as an example of a trace fossil. Jackson shows and discusses a rare fossilization process in which ants were caught in tree sap which later solidified as amber. Part 3 has title 'Geological maps' and is presented by R.C.L. Wilson. Chris Wilson uses the Cheddar sheet to discuss unconformities. On an enlarged version of the S.E. corner of the sheet he points out the junction between the Carboniferous limestone and the overlying Triassic rocks. Wilson next superimposes a topographic map on the geological map and demonstrates how structure contours can be drawn. Wilson with a model of the valley shown on the map. The model is an approximation of the Carboniferous limestone surface before deposition of the Triassic sediments. The model is 'completed' by putting on the Triassic fill to show the present landscape.
Master spool number: 6LT/70354
Production number: 00521_2153
Videofinder number: 1711
Available to public: no