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The aim of this programme is to show what happens during the various stages of a geochemical survey. The pro grannie begins by Dr. C.H. Janes (University of Leicester) interpreting the results of a... stream sedinent survey for zinc in South Devon. Dr. Thorpe points out some of the problems of obtaining valid results, before returning to Dr. James to see how he tackled these problems. The film shows Dr. James conducting an orientation survey, his students in the field collecting sediment samples and in the laboratory analysing the results. Several examples of stream conditions effecting the results are shown and both absorption and emission spectroscopic methods of analysis are demonstrated. Finally, Dr. James' mathematical analysis of results is commented on by Dr. Thorpe who defines "population" end shows how anomalies are detected. The programme continues by Dr. James describing a follow-up survey of a zinc anomaly. Students from Leicester demonstrate on site chemical analysis techniques to locate the cut off accurately, and how they collect soil samples in traverses perpendicular to the suspected mineral vein. The programme ends by Dr. Janes describing a particularly interesting tin anomaly but before he can explain why, Dr. Thorpe fades out the film and poses the question to the student: "Where would you site the soil surveys to detect tin mineralisation in that area?" The anomaly map is given in the Broadcast Notes and by working through the problem the student will find out something characteristic of the way mineralisation can occur.
Metadata describing this Open University video programme
Item code: S2-2; 06
First transmission date: 14-10-1972
Published: 1972
Rights Statement:
Restrictions on use:
Duration: 00:24:00
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Producer: David Jackson
Contributors: C H James; Richard Thorpe
Publisher: BBC Open University
Keyword(s): Absorbtion and emission spectroscopic analysis; Anomalies; Mathematical analysis; Orientation survey; Result validity; Stream sediment survey; Tin mineralisation survey
Footage description: Shots of part of Leicester University campus. Shots of the office of Dr. C.H.James on campus. Dr. James is interpreting the results of a stream sediment survey for zinc in South Devon. Zinc ppm is shown on a map of the area. Differences in zinc ppm pattern between the granite areas of the north and sedimentary areas of the south discussed R.S.Thorpe points out some of the problems of obtaining valid results in a stream sediment survey. This survey shows an orientation survey being conducted. Shots of C.H. James testing the proposed analytical techniques to check that they will give good results. Shot of a map of the survey area showing streams and sampling places. Shots of a student taking samples of stream sediment. Commentary explains what areas are good sampling points and those which should be avoided. Shots of a student analysing the sediment using a spectroscopic technique. A diagram is used to explain the principles of this technique. Shots of a direct reading optical emmission spectrometer being used for multi-element analysis.Diagram is used to show how the apparatus works. Results are calibrated and printed out by computer. Shot of Computer print-out. R.S.Thorpe defines "population" in the survey above and comments on C.H.James' mathematical analysis. Thorpe explains how James arrived at his four populations. He uses a graph as an aid. C.H.James describes the follow up survey of zinc anomalies in South Devon. Shot of chart of the streams sampled. The zinc anomaly figures are shown on the chart. Film sequence shows a Leicester University student collecting and analysing samples of stream sediments in the field. Shots of Leicester University field workers surveying and sampling at sites on either side of the stream. Commentary explains the process of obtaining soil samples. Shots of a diagram showing the stream with the analytical figures from the soil survey plotted on either side. R.S.Thorpe introduces the next sequence. Shot of a chart showing tin anomalies for a stream in the same area. Commentary by C.H.James briefly explains the situation. R.S.Thorpe asks student to determine sites for soil analysis which will detect tin mineralisation. Students should use the data provided by C.H.James above.
Master spool number: 6HT/70692
Production number: 00525_1053
Videofinder number: 1648
Available to public: no