Free geology lab tools
Calculators and practice for structural geology and petrography labs. Each shows its formula and the steps to do it by hand.
Interactive stereonet
Plot planes, poles and lines on a lower-hemisphere equal-area (Schmidt) or equal-angle (Wulff) net. Find intersections, angles between planes and lines, rake, apparent dip and fold axes.
Three-point problem solver
Enter three points on a plane (east, north, elevation) and get its strike and dip, with the textbook construction shown step by step.
True thickness and depth calculator
Calculate the true thickness of a bed from its outcrop width and dip on flat or sloping ground, and the depth to a bed at a given distance.
Mohr circle calculator
Normal and shear stress on a plane from σ1, σ3 and the angle to the plane, drawn on a Mohr circle, with an optional Coulomb failure envelope and tensile strength.
Strike and dip converter
Convert a plane between right-hand-rule azimuth, dip direction/dip and quadrant notation, and get its pole.
Practice problems and worksheets
Random stereonet, map, stress and identification problems with worked solutions, printable worksheets with answer keys, bubble answer sheets and a grader.