Device and method for ground surveying

An arrangement for ground surveying, comprising:

• at least two rods and
• a measurement device configured to feed measurement currents to and measure received currents from said ground current electrodes;
• wherein each of said at least two rods comprises:
• an elongate shaft with a first end and a second end and
• a bead formed by or attached to the first end of the shaft, for easing the penetration of the rod into ground under application of force from the direction of the second end of the shaft or for generating a particular effect when force is applied to the rod once it has penetrated into ground,
• a plurality of ground current electrodes located at intervals along at least a part of the length of the shaft, and
• ground current connections between said ground current electrodes and and wherein:
• said connection points are located either within the rod closer to the second end of the shaft than any of said plurality of ground current electrode or beyond the second end of the shaft,
• said ground current electrodes are releasably coupled to the shaft,
• the shaft is tubular,
• at least some of the ground current electrodes are located inside the tubular shaft, and
• said tubular shaft is configured to slide off in its longitudinal direction, for exposing said at least part of the ground current electrodes.

A method for ground surveying, comprising:

• sinking at least two rods into ground within a target volume of ground,
• feeding measurement currents to at least a first portion of the ground current electrodes comprised in said at least two rods,
• measuring received currents from at least a second portion of the ground current electrodes comprised in said at least two rods, and
• generating a three-dimensional model of ground characteristics in at least a part of said target volume of ground based on calculations from said measurement currents and received currents, wherein each of said at least two rods comprises,
• an elongate shaft with a first end and a second end and
• a head formed by or attached to the first end of the shaft, for easing the penetration of the rod into ground under application of force from the direction of the second end of the shaft or for generating a particular effect when force is applied to the rod once it has penetrated into ground,
• a plurality of ground current electrodes located at intervals along at least a part of the length of the shaft, and
• ground current connections between said ground current electrodes and respective connection points;
• and wherein,
• said connection points are located either within the rod closer to the second end of the shaft than any of said plurality of ground current electrodes or beyond the second end of the shaft,
• said ground current electrodes are releasably coupled to the shaft,
• the shaft is tubular,
• least some of the ground current electrodes are locate inside the tubular shaft, and
• said tubular shaft is configured o slide off in its longitudinal direction, for exposing said at least part of the ground current electrodes.