Ive been studying beach-ball diagrams and have the general idea behind it but I think if I get the answers to these samples it will stick. This is not homework but is important because I have a test in the morning. http://serc.carleton.edu/files/NAGTWorkshops/structure04/Focal_mechanism_primer.pdf page 3, can someone help me with the answers so I can compare to mine. http://imgur.com/didhYoP this is my attempt at the first 3. How does one determine the direction of the small line? is that the dip direction? how does one determine the strike line for oblique faults? how do i tell what is up and down. sorry for the basic questions and thanks in advance.