3. INTRODUCTION TO UTM COORDINATES AND MAP DATUMS

4. UTM COORDINATES ZONE CENTRAL MERIDIAN = 500,000 m 300,000 700,000 500,000 108102 105

5. TRANSVERSE MERCATOR

6. UTM ZONES UNITED STATES NM

7. UTM CARTISIAN COORDINATES

8. USGS MAPS AND UTM

9. COORDINATE SYSTEMS NAD 27 = North American Datum, 1927 NAV 29 = North American Vertical, 1929 NAD 83 = North American Datum, 1983 WGS 84 = World Geodetic System 1984 (ALL GPS) CORPSCON – CONVERSION PROGRAM

10. INTRODUCTION TO MAGNETIC METHODS –Earth’s Magnetic Field –Rock Magnetism –Geologic Models Magnetic Anomaly Sources –Planning a Survey –Examples REFERENCE: Sheldon Breiner, Applications Manual for Portable Magnetometers www.georentals.co.uk/ampm-opt.pdf

11. TOTAL FIELD MEASUREMENTS

12. EARTH’S DIPOLE FIELD

13. MAGNETIC ELEMENTS H = F cos I Z = F sin I = H tan I X = cos D Y = H sin D X² + Y² = H² X² + Y² + Z² = F² F = Total Field Intensity I = Inclination D = Declination H = Horizontal Component X = North Component Y = East Component Z = Vertical Component East North

14. TOTAL INTENSITY 25 70 X 1000 nTeslas 50

15. GEOMAGNETIC INCLINATION 60N 80N 0 80S 60S GEOMAGNETIC INCLINATION DEGREES OF ARC FROM HORIZONTAL

16. CHANGES IN DECLINATION AND INCLINATION AT LONDON SINCE 1540 SECULAR VARIATIONS 2010 Declination Inclination

17. SOLAR DIURNAL VARIATIONS MID NORTHERN AND MID SOUTHERN LATITUDES 50 nT EQUATORIAL LATITUDES

18. MICRO PULSATIONS 10 nT 10 minutes

19. TYPICAL MAGNETIC STORM 50 nT 1 day

20. CORRECTING FOR TIME VARYING FIELDS F = f(x,y,z,t) –x = Easting (Longitude) –y = Northing (Latitude) –z = Elevation (very small effect) –t = time F B = Field at Base Station (time dependent) F R = Field at Rover (space/time dependent) F C = Time Correct Field at Rover = F B – F R GEOREF = Geomagnetic Reference Correction

21. AVERAGE MAGNETIC SUSCEPTIBILITIES BASIC IGENOUS ACID IGNEOUS METAMORPHIC SEDIMENTARY Magnetic Susceptibility x 10 6 (c.g.s.)

22. MEASURED SUSCEPTIBILITIES OF ROCK MATERIALS MaterialK x 10 6 cgsAt H, Oe Magnetite300,000-800,0000.6 Pyrrhotite125,0000.5 Ilmenite135,0001.0 Franklinite36,000 Granite28-27001.0 Diorite46.81.0 Gabbro68-23701.0 Basalt6801.0 Sandstone161.0

23. INDUCED VS REMANENT MAGNETIZATION Induced Magnetization –Polarization in direction of Earth’s Field Remanent Magnetization –Thermoremanent (Curie Temperature) –Detrital (Depositional) –Chemical

24. GEOLOGICAL MODEL REPRESENTATIONS OF COMMON MAGNETIC ANOMALY SOURCES

25. Dipoles vs. Monopoles vs. Arrays of Poles

26. ANOMALIES FOR GEOLOGICAL BODIES AT VARIOUS ORIENTATIONS AND FIELD INCLINATIONS ↓ F F →F T N-S T E-W T N-S T E-W 1234512345

27. TOTAL INTENSITY INDUCED DIPOLE SIGNATURES AT VARIOUS INCLINATIONS OF THE FIELD Induced dipole Vertical Field (North or South Poles) Induced dipole (Inclination 60 º) Induced dipole Equatorial Field (Inclination 0 º)

28. REMANENT DIPOLE SIGNATURES MOMENT NOT PARALLEL TO INDUCING FIELD

29. EFFECT OF DEPTH ON ANOMALY WIDTH The amplitude of the anomaly is maintained constant By adjusting the size of the anomalous body.

30. DEPTH/AMPLITUDE BEHAVIOR OF DIPOLE ANOMALIES M 8MM Note: Same Amplitude but Change in width

31. F DISTANCE nT 500 100 1 10 20010Ft 1 ton iron

32. ANOMALIES OF COMMON OBJECTS OBJECT Ft/nT Ft/nT Automobile (1 ton) 30/40 100/1 Ship (1000 ton) 100/300-700 1000/1 Aircraft (light) 20/10-30 50/1 Pipeline (12”) 25/50-200 50/12-50 Wellhead 50/200-500 500/2-5 Fenceline 10/15 25/1-2 Rifle 5/10-50 10/ 2-10 Revolver 5/10-20 10/1-2

34. TYPICAL MAGNETIC ANOMALIES OF COMMON ARCHAEOLOGICAL FEATURES Kiln-baked brick wall Sandstone wall in more magnetic soil Shallow grave or pathway Humus-rich site of habitation Shallow tomb Deeply buried tomb Bricks in disarray Fire pit with bricks In original position

35. PLANNING A SURVEY SIZE OF TARGET AERIAL EXTENT OF SEARCH GROUND OR AIRBORNE RESOLUTION OF SURVEY FIELD METHODS PITFALLS EXAMPLES

36. TYPICAL SEQUENCES OF TRAVERSES DURING SEARCH PROCEDURES Secondary Traverse Primary Traverse Final Traverse Object location Total magnetic field contours (not known during search)

37. ESTIMATION OF DEPTH TO TOP OF ANOMALOUS BODIES USING MAXIMUM SLOPE

38. 52490 nT 52195 nT 52280 nT Contour Interval 5 nT GNTN Maximum slope 5 m

39. F DISTANCE nT 500 100 1 10 20010Ft 1 ton iron SOLUTION FOR BILLS CRATER

40. MAGNETIC EFFECT OF LATERAL SUSCEPTIBILITY CHANGE VS STRUCTURE

41. HIGH RESOLUTION AIRBORNE MAGNETIC MAP OF THE SAGE 2010 FIELD AREA SAGE 2005 SEISMIC PROFILE SAGE 2005 MT PROFILE SAGE 2010 ARCH SITE