Abstract: A measuring head for use in electrical measurements conducted in holes drilled in the ground comprises an elongated body, adaptable in the hole and comprising an electrode, electrically connecting the measuring head with its surroundings, for transmitting an electrical signal between the measuring head and its surroundings. In accordance with the invention, the measuring head comprises insulating means, placed on the body on both sides of the electrode along the length of the hole in order to form a measuring area, electrically insulated from other parts of the hole, around the electrode placed in the hole.

Abstract: A flow meter to be used in a hole drilled in the bedrock for measuring stream flows in bedrock fractures which are transversal to the hole. The flow meter comprises an elongated body having a cross section which is substantially smaller than the diameter of the hole; separating members placed at a distance from each other in the longitudinal direction of the body for separating the examined section from the other parts of the hole in a substantially pressure-tight manner; dividing members for dividing the examined section into two sectors in the longitudinal direction of the hole; and a flow channel extending through the body and equipped with a flow sensor for measuring the direction and rate of the flow between the sectors. In accordance with the invention, the dividing members are formed of thin and elastic sealing strips, which have been fixed to the body and, being substantially perpendicular to the surface of the body, arranged to surround and delimit the sectors.

Abstract: A flow meter to be used in a hole drilled in the bedrock for measuring stream flows in bedrock fractures which are transversal to the hole. The flow meter comprises an elongated body having a cross section which is substantially smaller than the diameter of the hole; separating members placed at a distance from each other in the longitudinal direction of the body for separating the examined section from the other parts of the hole in a substantially pressure-tight manner; dividing members for dividing the examined section into two sectors in the longitudinal direction of the hole; and a flow channel extending through the body and equipped with a flow sensor for measuring the direction and rate of the flow between the sectors. In accordance with the invention, the dividing members are formed of thin and elastic sealing strips, which have been fixed to the body and, being substantially perpendicular to the surface of the body, arranged to surround and delimit the sectors.

Abstract: A measuring head for use in electrical measurements conducted in holes drilled in the ground comprises an elongated body, adaptable in the hole and comprising an electrode, electrically connecting the measuring head with its surroundings, for transmitting an electrical signal between the measuring head and its surroundings. In accordance with the invention, the measuring head comprises insulating means, placed on the body on both sides of the electrode along the length of the hole in order to form a measuring area, electrically insulated from other parts of the hole, around the electrode placed in the hole.

Abstract: A measuring procedure and a flowmeter for the measurement of liquid flow in a hole bored in the ground, such as rock. The flowmeter consists of a long cylindrical body comprising: ring-shaped sealing elements (5) placed at a distance from each other in the longitudinal direction to seal off a certain volumetric section from the rest of the hole; dividing elements (6) for dividing the volumetric section into at least three sectors (1) extending from one sealing element to the other; flow ducts (2) interconnecting the sectors; an impulse source (3) placed at the junction of the flow ducts; and sensors (4) placed in the flow ducts for measuring the magnitudes and velocities of currents between sectors by monitoring the velocity and direction of motion of an impulse.

Abstract: Flowmeter for locating zones containing currents in a bore hole made in a rock. The flowmeter comprises parting elements (1) for separating a measurement section (3) in the hole from the rest of the hole in a substantially pressure-tight manner; an open flow duct (4) forming a free flow link between the hole portions on opposite sides of the flowmeter past the measurement section; and a measuring duct (5) leading from the section under measurement to a point outside it, together with measuring equipment (6), for measuring the magnitude and direction of flow between the measurement section and the hole portion outside it.