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==Advantages and disadvantages of core orientation techniques==

==Advantages and disadvantages of core orientation techniques==

Numerous studies have been done to determine the accuracy of different orientation techniques. Nelson et al.<ref name=pt03r37>Nelson, R. A., Lenox, L. C., Ward, B. J., 1987, Oriented core—its use, error, and uncertainty: AAPG Bulletin, v. 71, n. 4, p. 357–367.</ref> provides a particularly comprehensive review of error sources for mechanical orientation and comparisons of accuracy with other techniques. Core orientation techniques are capable of achieving, under optimum conditions, accuracies of ≤5°. Sources and severity of errors depend on many factors, some of which are listed here:

Numerous studies have been done to determine the accuracy of different orientation techniques. Nelson et al.<ref name=pt03r37>Nelson, R. A., Lenox, L. C., Ward, B. J., 1987, [http://archives.datapages.com/data/bulletns/1986-87/data/pg/0071/0004/0350/0357.htm Oriented core—its use, error, and uncertainty]: AAPG Bulletin, v. 71, n. 4, p. 357–367.</ref> provides a particularly comprehensive review of error sources for mechanical orientation and comparisons of accuracy with other techniques. Core orientation techniques are capable of achieving, under optimum conditions, accuracies of ≤5°. Sources and severity of errors depend on many factors, some of which are listed here:

* At high latitudes, most techniques are prone to failure for similar reasons: the inclination of the ambient earth's field makes an accurate measurement of azimuth difficult.

* At high latitudes, most techniques are prone to failure for similar reasons: the inclination of the ambient earth's field makes an accurate measurement of azimuth difficult.