| Abstract [eng] |
Measurement of gravity anomalies gives precise and more detail information about Earths gravity field and its changes. This information is needed in geodesy, geophysics, navigation and other scientific research. It is also relevant in scientific and practical geodesy in Lithuania. The more precise geodesical measurements, the more important measurements of gravity anomalies become. It is important to investigate possible methods of gravity anomaly measurements and it is accuracy in Lithuania. To do that we measured gravity field analysis, gravimetric measurement data processing of geodetic vertical network line of Vilnius–Molėtai–Kuktiškės and measurements of gravity anomalies. Bouguer anomaly difference between the average values of network line of Vilnius–Molėtai–Kuktiškės and its root mean square error are precision indicators. Bouguer anomalies where determined on the basis of ArcGIS ArcMap software 1:200 000 of Lithuanias territory Bouguer anomalies map data also from Lithuanias gravimetrical base data, global gravity field models of network data points and everything was set on global gravity field model spreadsheet. It was determined that results of gravimetrically measured Bouguer anomalies were closest to those of Lithuanias 1:200 000 Bouguer anomaly map and EGM2008 models spreadsheet. The mean difference between measured and determined average value of Bouguer anomalies map was 0,212 mGal, root mean square error was 1,019 mGal. The difference between measured and determined Bouger anomaly values from EGM2008 model spreadsheet was 0,394 mGal, root mean square error was 0,837 mGal. Structure: introduction, 3 chapters, conclusions and references. Thesis consists of 72 pages of text without appendixes, 54 pictures, 7 tables, 91 bibliographical entries. |
