During the period 1982–86, a team of geologists from BGS carried out a programme of regional geological mapping and geochemical exploration in collaboration with the Zimbabwe Geological Survey under a Technical Co-operation agreement supported by the UK Department for International Development (DFID) (formerly ODA). Three regions of Zimbabwe were mapped and the results of the stream sediment geochemical surveys were presented as three reports.
- Dunkley, P.N. 1987. A regional drainage geochemical exploration survey of the Harare area, Zimbabwe. Research report of the British Geological Survey, No MP/87/18.
- Dunkley, P.N. 1987. A regional drainage geochemical exploration survey of the country between Rushinga and Nyamapanda, north-east Zimbabwe. Research report of the British Geological Survey, No MP/87/16.
- Dunkley, P.N. 1987. A regional drainage geochemical exploration survey of the Makaha area, north-east Zimbabwe. Research report of the British Geological Survey, No MP/87/17.
These reports are available through the BGS sales desk.
This work pre-dated the desktop PC era and the analytical data was stored on a Cifer 1880 microcomputer and PDP11 magnetic tapes. These data have recently been transferred to PC format and stored as a CD-ROM database. Some of the XRF data was lost from the original PDP11 tapes and these results are now represented as absent data (-1). Several erratic Ta and Ba highs from the Rushinga and Nyamapanda data set have also been replaced with -1. In the original reporting it is believed that these records were removed from the data set and this accounts for the difference in the number of samples reported here and those used in the technical report.
During preparation of the CD-ROM the data has also been ‘cleaned’ by replacing all 0 (below detection values) with a value 2/3rds the reported detection limits (rounded to an integer) i.e.
| Element | Detection Limit (ppm) | Substitute Value |
|---|---|---|
| Cu | 1 | 1 |
| Pb | 9 | 6 |
| Zn | 3 | 2 |
| Co | 3 | 2 |
| Ni | 2 | 1 |
| Mn | 26 | 18 |
| Li | 1 | 1 |
| Sn | 4 | 3 |
| W | 4 | 3 |
| Ta | 5 | 3 |
| Ba | 54 | 36 |
| As | 10 | 7 |
The precision of analytical methods is discussed in the reports.
All samples have UTM grid co-ordinates (UTM Zone 36K, Modified Clarke Spheriod 1880 (S.A.)). These co-ordinates have been modified since the original report to be full Easting and Northing grid references – this required an “8” to be prefixed to the original Northings.
Each data record includes a ‘LithUnit’ and ‘RockType’. These are explained in each of the reports referenced previously.
| Area | Harare | Rushinga & Nyamapanda | Makaha |
|---|---|---|---|
| Excel filename | HARARE.XLS | RUSHNYAM.XLS | MAKAHA.XLS |
| CSV filename | HARARE.CSV | RUSHNYAM.CSV | MAKAHA.CSV |
| DBF filename | HARARE.DBF | RUSHNYAM.DBF | MAKAHA.DBF |
| Minimum Easting | 261497 | 393429 | 446924 |
| Maximum Easting | 340763 | 498990 | 490347 |
| Minimum Northing | 8009393 | 8092815 | 8072997 |
| Maximum Northing | 8064319 | 8 181461 | 8092859 |
| Number of sites | 1603 | 12464 | 3298 |
| Average density (sample per km²) | 2.7 | 1.55 | 3.8 |
| Fraction used | -80# | -80# | -80# |
| Elements by AAS | Cu, Pb, Zn, Co, Ni, Mn, and Li | Cu, Pb, Zn, Co, Ni, Mn, and Li | Cu, Pb, Zn, Co, Ni, Mn, and Li |
| Elements by XRF | As, Ba, Sn, Ta and W (+ Pb and Ni) | As, Ba, Sn, Ta and W (+ Pb and Ni) | As, Ba, Sn, Ta and W (+ Pb and Ni) |
Reference to the CD-ROM should be as follows:
BGS (2007). Zimbabwe Regional Geochemical Survey CD-ROM. Version 2.0. BGS International Regional Geochemistry CD-ROM Series, No.2 Zimbabwe. British Geological Survey, Keyworth, Nottingham,UK
BGS work in Zimbabwe
Central enquiries
British Geological Survey
Keyworth
Nottingham NG12 5GG
United Kingdom
Tel: +44 (0)115 936 3143
Fax: +44 (0)115 939 3276
Email: enquiries@bgs.ac.uk
Collaborating organisation: Zimbabwe Geological Survey
Director
Geological Survey Department
P O Box CY 210
Causeway
Harare, Zimbabwe
Email: zgs@africaonline.co.zw
| readme.doc | Information file in MS Word format |
| readme.pdf | Information file in PDF format |
| makaha.csv | Makaha geochemical data in comma separated variable format |
| makaha.xls | Makaha geochemical data in MS Excel format |
| makaha.dbf | Makaha geochemical data in dbf format |
| harare.csv | Harare geochemical data in comma separated variable format |
| harare.xls | Harare geochemical data in MS Excel format |
| harare.dbf | Harare geochemical data in dbf format |
| rushnyam.csv | Rushinga & Nyamapanda data in comma separated variable format |
| rushnyam.xls | Rushinga & Nyamapanda data in MS Excel format |
| rushnyam.dbf | Rushinga & Nyamapanda data in dbf format |
Purchase information
You may also be interested in:
Applied geochemistry
Since the 1960s, the BGS has amassed considerable geochemical data holdings and developed significant expertise in applied geochemistry.
International geochemistry CD-ROM series
Regional geochemical data from a range of overseas countries are available on a series of CD-ROMS.