A tiltmeter is a sensitive inclinometer designed to measure very small changes from the vertical level, either on the ground or in structures. Tiltmeters are used extensively for monitoring volcanoes, the response of dams to filling, the small movements of potential landslides, the orientation and volume of hydraulic fractures, and the response of structures to various influences such as loading and foundation settlement.
The modern electronic tiltmeter, which is slowly replacing all other forms of tiltmeter, uses a simple bubble level principle, as used in the common carpenter level. An arrangement of electrodes senses the exact position of the bubble in the electrolytic solution, to a high degree of precision. Any small changes in the level are recorded using a standard datalogger. This arrangement is quite insensitive to temperature, and can be fully compensated, using built-in thermal electronics.
