Orientation Errors of Paleomagnetic Samples When Using a Magnetic Compass and Possible Ways to Overcome Them

Abstract

A paleomagnetic study of volcanic rocks of the Okhotsk-Chukotka volcanic belt was performed to identify the scale and distribution pattern of orientation errors associated with the use of a magnetic compass, as well as to find how they influence the accuracy of calculated mean directions at both site and regional levels. The impact of these errors on the position of the final paleomagnetic pole and the dispersion of virtual geomagnetic poles, which is a common measure of the amplitude of paleosecular geomagnetic variations, was assessed. The alternative (non-magnetic compass) methods for orienting paleomagnetic samples were analyzed. Their advantages and disadvantages were outlined. A new method for orienting paleomagnetic samples using a theodolite equipped with a laser pointer was proposed. This method has a distinct advantage over previous alternatives as it is not limited by certain critical factors.

Keywords

• solar compass
• magnetic compass
• orientation errors of paleomagnetic samples
• alternative orientation methods