ASSESSMENT REPORT N 0. REPORT ON HORIZONTAL COPLANAR LOOP ELECTROMAGNETIC SURVEY HOUSTON AREA OF BRITISH COLUMBIA AQUITAINE COMPANY OF CANADA DURING

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1 tf REPORT ON HORIZONTAL COPLANAR LOOP ELECTROMAGNETIC SURVEY IN THE HOUSTON AREA OF BRITISH COLUMBIA BY AQUITAINE COMPANY OF CANADA c DURING MARCH 21 - MARCH 25, 1977 MINERAL RESOURCES BRANCH ASSESSMENT REPORT + - N 0. G. Hendrickson F.

2 AQUITAIP COMPANY OF CANADL "6233 I,

3 TABLE OF CONTENTS INTRODUCTION DESCRIPTION OF METHOD AND IN STRUMEN TAT ION Page 1 1 GEOLOGY PRESENTATION OF RESULTS DISCUSSION OF RESULTS CON C LUS ION.

4 1. r INTRODUCTION During the period of March 21 to March , a Aquitaine geophysical crew carried out a detailed horizontal coplanar loop electromagnetic survey on a Turam anomaly located on the HAGAS claims approximately 28 miles southwest of Houston8 B.C. Access to the survey * area is by logging roads which run along the Morice River. There was a good chance the previous owner of this property had drilled the anomaly from the wrong side. The effects of conductive overburden often makes conductors appear more vertical than they really are. Horizontal loop electromagnetic surveying generally gives a good indication of dip. DESCRIPTION OF METHOD AND INSTRUMENTATION 8' The Maxmin I1 instrument was used on this survey. Topographic surveying was done with a portable inclinometer. The topographic profile gives the information required to maintain the coils horizontal and coplanar. The necessary corrections to the in-phase data were made. These corrections were due to the variations in the coil separation resulting from the desire to keep the coils at a fixed horizontal separation. Measurements were taken of the in-phase and quadrature components of the secondary field expressed in percent of the primary transmitted field. Coil separations used on this survey were 100 meters and 150 meters. Frequencies used were 222 Hz, 444 Hz8 888 Hz Hz and 3555 Hz. GEOLOGY The property lies within the Hazelton Volcanics. No outcrop appears near the anomaly, however the drilling results showed the anomaly lies within a mixed sequence of volcanics. PRESENTATION OF RESULTS r The results of this survey are presented on the accompanying plates. Scales used are as follows: 1 cm = 25 meters (vertical and horizontal distance) 1 cm = 10% (EM) I cm = IOOY (Magnetics)..

5 2. c All direction indications in this report refer to GRID NORTH not geographical north. DISCUSSION OF RESULTS The 1973 Turam grid was not recoverable however LINE IN was made to coincide with the former L16NE as close as possible. The baseline used for this survey bears no relationship to the baseline used for the 1973 Turam survey. The location of the drill holes relative to this survey should be established when the snow is gone. The background electromagnetic response gives information on the overburden. The east side of the grid has thick conductive overburden. Overburden thickness appears to vary from 25 to 50 meters. Resistivity of the overburden appears to be around 40 OHM meters. The west side of the grid does not have as much overburden. f- The thicker conductive overburden to the east may make the anomaly appear to be dipping east. The best response is on line 2N. Here the conductivity thickness product is approximately 10 MHOS. The appreciable width and the apparent magnetic correlation may establish this anomaly as a drill target. The effect of the conductive overburden is to make the anomaly appear shallower than it actually is thus any drilling done should be aimed at intersecting the anomaly 50 meters below the surface. Interpretation of the dip is not as easy as was hoped. There are conflicting indications of dip, however all the evidence on hand is slightly in favor of a west dip. The bend in the conductor may be due to faulting along strike. CONCLUSION r. This anomaly has now been studied with two geophysical methods both capable of good depth penetration. Both surveys have indicated an anomaly of moderate conductivity which has yet to be explained by drilling. The next drill hole should be drilled from the west side of LINE 2N to intersect the anomaly fifty meters below the surface. A detailed examination of the previous core should be done before any more dri lling.

6 VALUATION OF WORK r AIR TRAVEL G. Hendrickson -. M. Hendrickson $ Calgary-Smithers-Calgary $ Ke lowna-smi t hers-kelowna GROUND TRANSPORTATION 3/4 Ton GMC $ March 21 - March 25 Snow Mobile Rental $ March 21 - March 25 Gas & O i l $ FOOD AND ACCOMODATION March 21 - March 25 $ WAGES G. Hendri ckson $63/day M. Hendrickson $35/day $ March 21 - March 25 $ March 21 - March 25 INSTRUMENT RENTAL MAXMIN I1 EM iil $18/day $ March 20 - March 26 Magnetometer MF-2 iil $8/day$ March 20 - March 26 EQUIPMENT INSURANCE $ EQUIPMENT SHIPPING COSTS $ REPORT CHARGE $ TOTAL $ F',

7 C STATEMENT OF QUALIFICATION Grant Hendrickson B.Sc. B.Sc. (Geophysics) University of British Columbia For the past five years I have been actively involved in Mining Geophysics in Canada, the United States and Venezeula. One year was spent as a Mining Geologist working underground at the Granduc Mine. The bulk of my experience has been on the conducting and interpretation of electromagnetic, magnetics, resistivity and Induced Polarization surveys.,

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