I am trying to find out a method of determining the area below a curve. The end points of the curve are known in cartesian space, and the curvature of the curve is known. A diagram of the curve is here, shown in the images belowthis webpage ß must be in radians Where; MD = Measured Depth between surveys in ft I1 = Inclination (angle) of upper survey in degrees I2 = Inclination (angle) of lower in degrees Az1= Azimuth direction of upper survey Az2 = Azimuth direction of lower survey RF = Ratio Factor ß is the dog leg angle. I'm trying to find the area between the curve and a line projected downwards onto the bottom plane. I have a wellbore trajectory which gives x,y,z, coordinates (northing,easting,vertical depth)and the angle DL, and I am trying to find the net area above and below a certain depth plane by using the wells directional survey. Any suggestions would be appreciated, thanks!