ISSN 0016-7126 (Print)

ISSN 2587-8492 (Online)

The article studies the properties of the high-degree gravity field model EGM-2008 in the calculation of integral characteristics at large distances several times greater than the spatial resolution of the model. As an example of an indirect evaluation of a high-degree model, a gravimetric correction was computed into the sum of the measured elevations along the line of the high-precision I class leveling of the Krasnovodsk – Chardzhou line located in Turkmenistan. Using the calculator ICGEM, the Bouguer anomalies were calculated at each point of the line, then the attraction of the Bouguer layer (used heights are from catalog) excluded for the transition to free-air anomalies. In parallel, for a direct evaluation of the model, a regular grid of Bouguer anomalies with a step of 2 angular minutes within line area was also obtained, which were then compared with the anomalies from the gravity map J-40 of scale 1 : 1 000 000. The obtained results showed the standard deviation of the model anomalies from the reference ones, slightly less than 1 mGal, and also the convergence of the total correction along the entire line within 0.5 mm, which is quite enough for the subsequent inclusion of the line into the adjustment of the polygons of high-precision leveling. If further calculations on lines in more complex physicsgeographic conditions will confirm the obtained results, then this method of finding a gravimetric correction can be recommended instead of using gravimetric charts, or at least outline the limits of application of the method

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(2017) Application of global geopotential models to high-precesion levelling processing. Geodesy and cartography = Geodezia i Kartografia, 78(8), pp. 2-9. (In Russian). DOI: 10.22389/0016-7126-2017-926-8-2-9 |