Hello, I need to get oriented blocks of the country rock surrounding strongly magnetic dikes. Because of that, the compass needle gets strongly deflected when approaching the intrusion. What's the best way to get an unaffected measurement of the orientation of the block? I've been suggested to explore with a sun compass/sun dial and/or test with phone compass apps such as FieldMove Clino.
Any recommendations would be great!
If the compass needle is being strongly deflected due to the presence of strongly magnetic dikes, it can be difficult to obtain an unaffected measurement of the orientation of the surrounding country rock. Here are some options you might consider:
1. Sun compass/sundial: Using a sun compass or sundial can be an effective way to determine the orientation of a rock surface. By aligning the compass or dial with the sun's position in the sky, you can determine the direction of north and therefore the orientation of the rock surface. However, this method can be difficult to use in areas with dense vegetation or limited sunlight.
2. GPS or total station surveying: GPS or total station surveying can be used to obtain precise measurements of the orientation of rock surfaces. These methods use satellites or a fixed base station to determine the location of the survey instrument and can provide accurate measurements even in areas with magnetic interference.
3. Phone compass apps: Phone compass apps, such as FieldMove Clino, can be used to obtain a quick measurement of the orientation of a rock surface. However, these apps may be affected by the presence of magnetic interference, so it is important to test their accuracy in the field.
4. Magnetic declination correction: Magnetic declination is the angle between magnetic north and true north, and varies depending on your location. By correcting for magnetic declination, you can obtain a more accurate measurement of the orientation of the rock surface. Many compasses have a built-in declination adjustment, or you can use an online calculator to determine the declination for your location.
It's important to consider the limitations of each method and choose the one that is most appropriate for your specific situation.
Did it work with the phone compass?? II guess is the easiest way to do it. Other apps, including digital geological compass, are available (eGEO). Good luck!
- Badges
- Science method