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UNIVERSITY OF SOUTH ALABAMA


 

 Structural Geology Spreadsheets

CommonPlane.xlsm: Calculates the strike and dip of a structural plane given two linear attitudes (not colinear) that lie in the plane. The results are presented in text and stereographic form. Can also be used to solve apparent dip problems where the strike of a plane is known, an apparent dip trend and plunge on the plane is known, and the true dip is required.

http://www.usouthal.edu/geography/allison/GY403/CommonPlane.xlsm

CommonPlane_cotan.xlsm: Calculates the strike and dip of a structural plane given two linear attitudes (not colinear) that lie in the plane. Uses the cotangent method and requires visual interaction with user to calculate a solution. Can be used to construct and submit for lab grade.

http://www.usouthal.edu/geography/allison/GY403/CommonPlane_Cotan.xlsx

CommonPlane2_cotan.xlsm: Calculates the true dip of a structural plane given (1) strike azimuth, and (2) an apparent dip trend and plunge that lies in the plane. Uses the cotangent method and requires visual interaction with user to calculate a solution. Can be used to construct and submit for lab grade.

http://www.usouthal.edu/geography/allison/GY403/CommonPlane2_Cotan.xlsx

ThreePoint.xlsm: Calculates the strike and dip of a structural plane that contains 3 points of known location and elevation. Also calculates the hydraulic gradient if the 3 points are water table elevations. Can be used to construct and submit for lab grade.

http://www.usouthal.edu/geography/allison/GY403/ThreePoint.xlsm

IntersectingPlanes.xlsm: Calculates the plunge and bearing of the intersection of 2 planar structures.

http://www.usouthal.edu/geography/allison/GY403/IntersectingPlanes.xlsm

IntersectingPlanes_cot.xlsx: uses the cotangent method to solve for the apparent dip angle given (1) the strike and dip of a plane, and (2) the trend direction of the apparent dip. Requires visual interaction with user for a solution. Can be used to construct and submit for lab grade.

http://www.usouthal.edu/geography/allison/GY403/IntersectingPlanes_Cotan.xlsx

IntersectingPlanes2_cot.xlsx: uses the cotangent method to solve for the true dip angle given a strike azimuth, and the trend and plunge of an apparent dip. Requires visual interaction from the user.

http://www.usouthal.edu/geography/allison/GY403/IntersectingPlanes2_Cotan.xlsx

IntersectingPlanes3_cot.xlsx: uses the cotangent method to solve for the trend and plunge of the line of intersection between two structural planes given the two strike and dip attitudes. Requires visual interaction from the user.

http://www.usouthal.edu/geography/allison/GY403/IntersectingPlanes3_Cotan.xlsx

Rotation.xlsm: Calculates the new orientation of a line given a starting orientation, a rotational axis orientation, and the amount and sense of rotation. The algorithm may also be used to find the rotated orientation of a structural plane if the orientation of the pole to the plane is used as the starting orientation.

http://www.usouthal.edu/geography/allison/GY403/Rotation.xlsm

SCslip.xlsm: Calculates the orientation of the slip vector given the attitude of the S and C planes measured from an S/C mylonite zone.

http://www.usouthal.edu/geography/allison/GY403/SCslip.xlsm

SphericalRotation.xlsm: Calculates the new geodetic position of a point on Earth given the starting geodetic coordinates (latitude/longitude), and the geodetic coordinates of the rotation axis, and the amount and sense of the rotation. This algorithm is typically used to track tectonic plate position over time given an absolute pole of rotation.

http://www.usouthal.edu/geography/allison/GY403/SphericalRotation.xlsm

Alidade_Datasheet.xlsm: reduces data taken with a standard alidade (stadia intercept, crosshair, vertical angle) and converts to the vertical and horizontal offset from the instrument base position.

http://www.usouthal.edu/geography/allison/GY403/ALIDADE_DataSheet.xlsm

Smart-Phone versions of above spreadsheets

Rotation.xlsx

CommonPlane.xlsx

IntersectingPlanes.xlsx

ThreePoint.xlsx

Web page maintained by:
David Allison

University of South Alabama

Department of Geology and Geography