Gradient (Tzz) versus Gravity (Tz) response

The following images provide an indication of gravity versus gradient signal/noise and resolution. Two stand-alone examples are used to compare high-resolution marine gravity and Full Tensor Gradient (FTG) data. The surveys overlap (bottom right) with gravity the larger and FTG the smaller. The image on the left compares the measured gravity (Tz) with a calculated gravity (Tze) from the gradiometer. The latter shows better discrimination of subsurface geology with its higher S/N ratio. The image on the right shows a calculated (1st vertical derivative) gradient Tzz response from gravity compared to the measured Gradient Tzz. The higher S/N ratio in the measured Tzz once again provides improved structural resolution. Thus, measured gradients are preferred and contain both higher resolution and valuable directional/shape and lineament information.

FTG-computed Tze Vs. measured Tz The big picture is measured Tz from a gravimeter and the overlapping small one is a computed Tze from FTG response	FTG-measured Tzz Vs. computed Tzz The big picture is a computed gradient to be compared to the overlapping small one that is FTG-measured Tzz

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