TY - JOUR

T1 - Observing Gravity Change in the Fennoscandian Uplift Area with the Hanover Absolute Gravimeter

AU - Timmen, Ludger

AU - Gitlein, Olga

AU - Klemann, Volker

AU - Wolf, Detlef

N1 - Funding Information: We appreciate the cooperation and the great efforts of the Nordic Geodetic Commission (NKG) and its Working Group on Geodynamics. We gratefully acknowledge the essential support of a number of colleagues from the Nordic countries and from Germany. The following institutions are participating in the joint project: Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences (Ås); Federal Agency for Cartography and Geodesy (Frankfurt); Finnish Geodetic Institute (Masala); Norwegian Mapping Authority (Hønefoss); Onsala Space Observatory, Chalmers University of Technology; Swedish Mapping, Cadastre and Land Registration Authority (Gävle); Technical University of Denmark, National Space Institute (Copenhagen). The research has been supported generously by the German Research Foundation (DFG) through the research grants MU 1141/3-1, 3-2 and 3-3 (‘‘Geotechnologien’’)

PY - 2012/8

Y1 - 2012/8

N2 - The Nordic countries Norway, Sweden, Finland and Denmark are a key study region for research of glacial isostasy. In addition, such research offers a unique opportunity for absolute gravimetry to show its capability as a geodetic tool for geophysical research. Within a multi-national cooperation, annual absolute gravity measurements have been performed in Fennoscandia by IfE since 2003. For the Hanover gravimeter FG5-220, overall accuracy of ±30 nm/s2 is indicated for a single station determination. First results of linear gravity changes are derived for ten stations in the central and southern part of the uplift area. Comparing with the rates predicted by glacial rebound modelling, the gravity trends of the absolute measurements differ by 3.8 nm/s2 per year (root-mean-square discrepancy) from the uplift model. The mean difference between observed and predicted rates is 0.8 nm/s2 per year only. A proportionality factor of -1.63 ± 0.20 nm/s2 per mm has been obtained, which describes the mean ratio between the observational gravity and height rates.

AB - The Nordic countries Norway, Sweden, Finland and Denmark are a key study region for research of glacial isostasy. In addition, such research offers a unique opportunity for absolute gravimetry to show its capability as a geodetic tool for geophysical research. Within a multi-national cooperation, annual absolute gravity measurements have been performed in Fennoscandia by IfE since 2003. For the Hanover gravimeter FG5-220, overall accuracy of ±30 nm/s2 is indicated for a single station determination. First results of linear gravity changes are derived for ten stations in the central and southern part of the uplift area. Comparing with the rates predicted by glacial rebound modelling, the gravity trends of the absolute measurements differ by 3.8 nm/s2 per year (root-mean-square discrepancy) from the uplift model. The mean difference between observed and predicted rates is 0.8 nm/s2 per year only. A proportionality factor of -1.63 ± 0.20 nm/s2 per mm has been obtained, which describes the mean ratio between the observational gravity and height rates.

KW - Absolute gravimetry

KW - Fennoscandian land uplift

KW - glacial isostatic adjustment (GIA)

KW - postglacial rebound (PGR)

UR - http://www.scopus.com/inward/record.url?scp=84866889208&partnerID=8YFLogxK

U2 - 10.1007/s00024-011-0397-9

DO - 10.1007/s00024-011-0397-9

M3 - Article

AN - SCOPUS:84866889208

VL - 169

SP - 1331

EP - 1342

JO - Pure and applied geophysics

JF - Pure and applied geophysics

SN - 0033-4553

IS - 8

ER -