Hydrogeologiczne przyczyny zmian przyspieszenia siły ciężkości na stanowisku w Obserwatorium Astronomiczno-Geodezyjnym w Józefosławiu

Abstract

Hydrogeological influences in the absolute gravity changes at Astro-Geodetic Observatory in Józefosław.A b s t r a c t . The article presents the results of measurements of gravity performed in the Astronomical and Geodetic Observatory Józefosław. Time series have been verified for parameters related to celestial bodies, atmospheric pressure changes and metrological factors. The analysis of these changes includes geodynamic and hydrological aspects taking into account global and local changes in groundwater levels. The aim of the article is to indicate the interpretation of contemporary measurements of gravity field againstthe contemporary accuracy of such measurements and to indicate the need for information on the level of groundwater (collected by the Polish Hydrogeological Survey) in procedures for the elaboration and interpretation of gravimetric measurements and support from hydrogeologists. Contemporary the gravity measurements with use of absolute gravimeters gives possibility determination of gravity value with uncertainty of the order 10–8 ms–2. Such accuracy corresponds to a vertical displacement of a point of less than 1 cm or a change in the water level of 2.5 cm. Use of gravimetric methods in the broadly understood Earth sciences must be supported by information related to changes in mass distribution around the measuring station, mainly related to the groundwater level changes. This allows to see the role of hydrogeological information related to the monitoring of groundwater as an indispensable information describing changes in the Earth’s gravity field.