Reduction of geometric leveling results to a system of normal heights using the global gravity models of the Earth

2018 ◽  
Vol 935 (5) ◽  
pp. 2-9
Author(s):  
K.I. Markovich
Keyword(s):  
Gravitational Field ◽  
Gravity Models ◽  
Mean Error ◽  
The Earth ◽  
Global Gravity ◽  
Normal Heights ◽  
The Republic ◽  
Acceleration Of Gravity ◽  
Gravity Acceleration ◽  
Global Gravity Models

The possible range of application of models of the Earth’s gravitational field is considered in the article by reducing the results of geometric leveling to a system of normal heights. The accuracy of the global gravity models EGM2008, EIGEN-6C4, GECO on the gravity acceleration differences calculated for the territory of the Republic of Belarus by the results of instrumental gravimetric measurements and obtained from gravity models was estimated. Areas of Belarus are determined for which the gravitational correction for the transition to the system of normal heights will be caused by the deviation of the level surfaces of the normal gravitational field from the actual, and not by the errors of the gravitational models in the form of acceleration of gravity. It is shown that the error of the gravitational correction obtained from the data of gravity models for the territory of Belarus is many times less than the permissible random mean error of geometric leveling of the first class.

Hydrogeology correction in the gravitational field from satellite data

2018 ◽  
Vol 931 (1) ◽  
pp. 2-7
Author(s):  
V.D. Jushkin ◽  
L.V. Zotov ◽  
O.A. Khrapenko
Keyword(s):  
Gravitational Field ◽  
Oil And Gas ◽  
Repeated Measurements ◽  
Geological Factors ◽  
Grace Satellite ◽  
Gas Pumping ◽  
Acceleration Of Gravity ◽  
Determination Of Parameters ◽  
Gravity Acceleration

The results of repeated measurements of the acceleration of gravity by the Russian absolute ballistic field gravimeter GABL-M on points of oil and gas deposits in the permafrost over a five year period are presented. The changes of gravity acceleration by the absolute gravimeter and GRACE satellite were compared. The results of comparisons of differences gravity acceleration by ballistic gravimeter GABL-M and relative Canadian gravimeters CG5 were [i]shown. The errors in determination of parameters of the gravitational field ballistic gravimeter GABL-M and CG5 gravimeters group were presented. The method of measurement with the gravimeter GABL-M and the method of determining the vertical gradients relative CG5 gravity meters was described. The necessity of introducing corrections of hydrogeology is caused by influence of hydro geological factors on the gravitational field in the permafrost. They are comparable with the values of the field change in the result of gas pumping.

Global gravity models and the Ghanaian Vertical Datum: challenges of a proper definition

Survey Review ◽  
2019 ◽  
pp. 1-11
Author(s):  
C. I. Kelly ◽  
S. A. Andam-Akorful ◽  
C. M. Hancock ◽  
P. B. Laari ◽  
J. Ayer
Keyword(s):  
Gravity Models ◽  
Global Gravity ◽  
Vertical Datum ◽  
Proper Definition ◽  
Global Gravity Models

scholarly journals Evaluation of GGMs Based on the Terrestrial Gravity Data of Gravity Disturbance and Moho Depthin Afar, Ethiopia

2021 ◽  
Vol 56 (3) ◽  
pp. 78-100
Author(s):  
Eyasu Alemu
Keyword(s):  
Gravity Data ◽  
Gravity Models ◽  
Moho Depth ◽  
Equal Distribution ◽  
Terrestrial Gravity ◽  
Global Gravity ◽  
Gravity Disturbances ◽  
Combined Models ◽  
Global Gravity Models ◽  
Best Fit

Abstract To estimate Moho depth, geoid, gravity anomaly, and other geopotential functionals, gravity data is needed. But, gravity survey was not collected in equal distribution in Ethiopia, as the data forming part of the survey were mainly collected on accessible roads. To determine accurate Moho depth using Global Gravity Models (GGMs) for the study area, evaluation of GGMs is needed based on the available terrestrial gravity data. Moho depth lies between 28 km and 32 km in Afar. Gravity disturbances (GDs) were calculated for the terrestrial gravity data and the recent GGMs for the study area. The model-based GDs were compared with the corresponding GD obtained from the terrestrial gravity data and their differences in terms of statistical comparison parameters for determining the best fit GGM at a local scale in Afar. The largest standard deviation (SD) (36.10 mGal) and root mean square error (RMSE) (39.00 mGal) for residual GD and the lowest correlation with the terrestrial gravity (0.61 mGal) were obtained by the satellite-only model (GO_CONS_GCF_2_DIR_R6). The next largest SD (21.27 mGal) and RMSE (25.65 mGal) for residual GD were obtained by the combined gravity model (XGM2019e_2159), which indicates that it is not the best fit model for the study area as compared with the other two GGMs. In general, the result showed that the combined models are more useful tools for modeling the gravity field in Afar than the satellite-only GGMs. But, the study clearly revealed that for the study area, the best model in comparison with the others is the EGM2008, while the second best model is the EIGEN6C4.

scholarly journals Moho topography, ranges and folds of Tibet by analysis of global gravity models and GOCE data

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Young Hong Shin ◽  
C.K. Shum ◽  
Carla Braitenberg ◽  
Sang Mook Lee ◽  
Sung -Ho Na ◽  
...  
Keyword(s):  
Gravity Models ◽  
Global Gravity ◽  
Global Gravity Models

scholarly journals Comparison and testing of GOCE global gravity models in Central Europe

2011 ◽  
Vol 1 (4) ◽  
pp. 333-347 ◽  
Author(s):  
Juraj Janák ◽  
Martin Pitoňák
Keyword(s):  
Reference Frame ◽  
Gravity Model ◽  
Central Europe ◽  
Terrestrial Reference Frame ◽  
Gravity Models ◽  
Direct Solution ◽  
Model Solutions ◽  
Global Gravity ◽  
Global Gravity Models ◽  
Global Gravity Model

Comparison and testing of GOCE global gravity models in Central EuropeThree different global gravity model solutions have been released by the European GOCE Gravity Consortium: a direct solution, a time-wise solution and a space-wise solution. To date, two releases of each solution have been issued. Each of these solutions has specific positives and weaknesses. This paper shows and analyzes the differences between each solution in Central Europe by means of comparison with respect to the EGM2008 and GOCO02S global gravity models. In order to make an independent comparison, the global GOCE models are tested by the SKTRF (Slovak Terrestrial Reference Frame) network in Slovakia.

scholarly journals LOCAL EVALUATION OF EARTH GRAVITATIONAL MODELS, CASE STUDY: IRAN

2017 ◽  
Vol 43 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Ismael FOROUGHI ◽  
Yosra AFRASTEH ◽  
Sabah RAMOUZ ◽  
Abdolreza SAFARI
Keyword(s):  
Gravity Data ◽  
Low Frequency ◽  
Gravity Anomalies ◽  
Gravity Models ◽  
Data Sets ◽  
Observation Data ◽  
Satellite Gravity ◽  
Global Gravity ◽  
Marine Gravity ◽  
Global Gravity Models

Global gravity models are being developed according to new data sets available from satellite gravity missions and terrestrial/marine gravity data which are provided by different countries. Some countries do not provide all their available data and the global gravity models have many vague computational methods. Therefore, the models need to be evaluated locally before using. It is generally understood that the accuracy of global gravity models is enough for local (civil, mining, construction, etc.) projects, however, our results in Iran show that the differences between synthesized values and observation data reach up to ∼300 mGal for gravity anomalies and ∼2 m for geoid heights. Even by applying the residual topographical correction to synthetized gravity anomalies, the differences are still notable. The accuracy of global gravity models for predicting marine gravity anomalies is also investigated in Persian Gulf and the results show differences of ∼140 mGal in coastal areas. The results of evaluating selected global gravity models in Iran indicate that the EIGEN-6C4 achieves the lowest RMS for estimating the geoid heights. EGM08 predicts the closest results to terrestrial gravity anomalies. DIR-R5 GOCE satellite-only model estimates the low-frequency part of gravity field more accurately. The best prediction of marine gravity anomalies is also achieved by EGM08.

Sign in / Sign up

Export Citation Format

Share Document