Local topographic features, meteorological conditions, currents, and the influences of the sun and moon must be considered to establish the tidal characteristics for a given area.

. Selection of mooring depth Tides may cause depth variations of a moored mine and can cause the mine to surface during low tide and be too deep during high tide.

. Mine sensitivity and damage width In areas where the tidal range is great, the position of a moored mine relative to the sea surface may vary significantly. As with the impact of water depth, increasing the depth of a mine will cause a reduction in its sensitivity, actuation width, and damage width.

. Submergence of reference buoys Reference buoys are used to mark the position of mines and as aids to navigation. If these buoys are deployed at low tide, they may become submerged during high tide.

Bottom sediments vary in porosity, water content, compactibility, and plasticity.

. Reverberation Bottom reverberation depends on frequency and grazing angle. Bottom scattering depends on sediment type and bottom roughness.

. Acoustic contrast Detecting and classifying mines with high-frequency mine hunting sonars creates a problem in acoustically distinguishing mines from the background.

. Bottom sediments (hardness) Initial penetration in silt or clay will be greater than rock, gravel, or a sandy bottom.

. Impact velocity Softer bottom types affect initial penetration more so than hard bottoms.

. Weight of the mine This causes subsequent penetration. This results from plastic flow (sediment flow out from under the mine upon impact), and/or scour and deposition.

. Angle of impact The more perpendicular the angle of impact, the greater the expected initial penetration.

. Mine movement A mine will not roll on a bottom composed of various mixtures of fine-grained sand, silt, and clay. Initial penetration into the bottom will prevent subsequent rolling.

. Mine burial Burial of a mine will have little influence upon a magnetic-actuated mechanism, but an acoustic signal may be attenuated by overlying sediment.

. Bottom clutter This phenomena results in non-mine targets being detected by a minehunting sonar system. This makes it difficult for the operator to identify targets from the ambient noise.

. Sediment resistivity This is the ability of sediment to conduct electrical current. Resistivity depends upon salinity, electrical conductivity of the sediment, and the thickness of the sediment.

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