E Chemex Labs Ltd
GROUND MAGNETOMETER SURVEY
Introduction
Ground magnetometer surveys were carried out on the Sidley Group of Claims by Larry Lehman in 1992 and 1993. In the first survey in 1992,30 m line spacings and intervals were used. In 1993, the line spacings and intervals were reduced to 15 m.
The area was covered twice, once using north
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south lines then using east-
westlines. the data used for this report deals with the 1993 data, with the lines running east
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west. The equipment used was borrowed from Crown Resources. The survey was loosely supervised by the Crown Resources geologist. The plotted data is included.On one set of maps the spacing between the lines is incorrectly plotted at 30 m (Maps 2 and 3). Map 4 shows correct line and station spacings but only the data north of the highway is available in suitable condition to include. Map 5 is a record of the raw data prepared by the author. With the exceptions noted on map 2, the contoured data appears to reflect the raw data provided by the operator.
The author of this report was not involved in any of the survey work. This report and interpretation are very aeneral in nature and by no means conclusive. This
interpretation has been done at the request of the stake holders, all information regarding the work performed on the survey, the maps (except Map 5), and the data were provided by L. Lehman. The author claims no responsibility for any of the data, information supplied by L. Lehman or the maps except Map 5. The information on Map 5 was copied from raw data supplied by L. Lehman. Map 5 was prepared to confirm the data on the contour maps and to provide a more complete record of the data using an appropriate scale.
The purpose of this report is to:
1. review the data with an intention to carry out future drilling programs 2. provide written confirmation of the work for an assessment report.
Survey Specifications
Magnetometer: make and model unavailable to the author at time of writing Station intervals: 15m
Line intervals: 15m Total coverage: 1 1 .I 8km Line Orientation: East
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west Operator: Larry LehmanContouring: Donezal Development Ltd.
Interpretation: C. Meredith Presentation
The data is presented in the form of 3 contour maps, Maps 2,3,4, and Map 5 which is the raw data. Maps 2 and 3 show contoured data north and south of the highway, the line interval is incorrect. They are plotted with line intervals of 30 m, on the ground the interval was 15m. Two known errors have been noted at the north boundary of Map 2.
Map 4 shows the contoured data with the correct line intervals but only the data north
of the highway is included. A map of the data south of the highway is available but it has been used extensively by the stake holder and has other information added such as the locations of reverse circulation drill holes, locations of things like fences, the line designations have been changed to suit the stake holder therefore it does not match the map for north of the highway so it has not been included. Map 5 shows the raw data plotted with correct line and station spacings.
The scale used is indicated on the appropriate map. Contour intervals used are to gammas. Map 1 shows the location of the grid on Lawless Claims 2 and 5.
Comparison of Maps 2, 3 and 4 shows that the main problem presented by the error in line spacings is that the highs change in their steepness and the lows are more well defined when the correct line spacings are used.
The total magnetic range is about 420 gammas, with low values of 56930 and a high of 57350. Three significant features have been noted:
1. north of the highway there is a roughly circular magnetic high about 140 m in diameter, it appears to widen to the north
2. on the eastern margin there is a long narrow area of lower magnetism 3. south of the highway there is a broader zone of higher magnetism.
Interpretation
This cursory interpretation is based largely upon personal information regarding regional trends shown by an airborne survey which covered a large area east of
Osoyoos. The area east of Osoyoos has a total magnetic field relief of 600 gammas * with a range from 56700 to 57300 gammas. The total magnetic field was interpreted as reflecting the general trend of the lithology which is west
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northwest. Thiscoincides with the geologic trends reported by Little in 1961 (GSC Map 15-1961).
Areas of low magnetism and anomalously quiet zones were interpreted as felsic plutons or alteration zones. Long narrow areas of low magnetism were interpreted as fault zones. Regional fault zones usually trend NE and N with some oriented EW.
1. Maanetic high north of the hiahwav
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this roughly circular area appears to broaden to he north. The presence of plagioclase diorite porphyry in outcrop suggests that it could represent this body. The Anarchist lithologies north of the highway are generally quite mafic including amphibolite and biotite gneisses. These lithologies could also produce a higher magnetic response. The mineralized greywacke mapped on the hillside east of the grid area would cause a magnetic high but it is suspected that this rock type would produce a higher response. It is interesting that the high in this area appears to consist of several small pods. This is consistent with the habit of the mineralized greywacke noted in the pits northeast of the grid area.2.Area of lower maanetism on the eastern marain of the grid
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this could reflect a less magnetic felsic or siliceous zone or a fault. The rocks on the ground support either interpretation. The area on the hillside adjacent to the grid area is heavily silicified.Shearing and breccia noted in outcrop adjacent to the grid area suggest faulting probably with a northerly trend. The presence of a felsic intrusion is not supported by nearby outcrops.
3. Maanetic hiah south of the highwav
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this area is broader with a lower magnitude, it probably reflects the lithology of the area. It is probably similar to the area north of thehighway but it is slightly less mafic.
There are some roughly circular lows adjacent to the northern high. These could represent small zones of alteration but they may be too small to be significant.
Conclusions
1. The data as presented on the contour maps prepared by Donezal has to be viewed with caution, when plotting future work sites on the ground but they can be used to aid in interpretation of the data, therefore, they have been included.
2. The area of magnetic low adjacent to the high, located north of the highway could warrant future investigation by drilling.
3. The magnetic data supports the lithologic and structural information obtained from outcrop observations in the area.
Recommendations
1. Electrical survey to determine better evidence of location of fault zones, probably IP.
2. Diamond drilling of targets selected on the basis of the magnetic and electrical data.
3. Lacking an electrical survey, drill targets could concentrate on the boundary between the magnetic high and low areas.