Heave
Heave turns up in 2 fields: hydrography, mining. Here is what it means to the people in each one.
Heave in hydrography
The vertical up-and-down motion of a vessel caused by waves, measured and removed from sonar depths.
The short-period vertical motion of the vessel about its mean level, estimated by integrating accelerations in the motion sensor. Real-time heave relies on a filter that struggles with long-period swell and sharp turns, so many surveys apply delayed or post-processed heave instead. Uncorrected heave shows as ripples along track that mimic sand waves. Induced heave, from the lever arm between sensor and transducer during roll and pitch, must also be handled.
"Heave's leaking through in this long swell, apply the delayed heave before you call those sand waves."
Heave in mining
The horizontal displacement of a rock stratum or vein caused by a geological fault.
Heave is the measure of horizontal separation between two sides of a faulted vein or rock layer. When a fault breaks and shifts a continuous ore body, miners measure the heave to know how far sideways they must drive a tunnel to locate the continuation of the pay zone. It is the horizontal counterpart to the vertical throw of a fault.
"The fault cut off our seam, and the geologists calculate a heave of about twenty meters to the east."