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1

Absolutne pomiary grawimetryczne w Polsce

100%

Sas-Uhrynowski A. , Cisak M.

Prace Instytutu Geodezji i Kartografii

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2001

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tom T. 48, z. 103

193--216

PL

Założona w latach 1994–1999 nowa podstawowa osnowa grawimetryczna kraju oparta została na 12 punktach absolutnych. Pomiary na tych punktach zostały wykonane pięcioma grawimetrami balistycznymi. Wyniki powtórnych pomiarów, wykonanych na kilku punktach różnymi grawimetrami, wykazały różnice dochodzące do 30 mikrogali. Zaszła zatem konieczność przeprowadzenia weryfikacji tych pomiarów. W tym celu wykonano pomiary względne zespołem czterech grawimetrów Lacoste & Romberg na 25 przęsłach łączących 12 punktów absolutnych. Przeprowadzona analiza umożliwiła zaakceptowanie pomiarów wykonanych tylko trzema grawimetrami – FG 5-101, FG 5-107 i JILAg 5, których wskazania nie różniły się więcej niż 3 mikrogale. Grawimetry te uznano za reprezentujące międzynarodowy standard grawimetryczny i ich wskazania przyjęto jako wzorzec dla polskiej grawimetrycznej osnowy podstawowej.

EN

New basic gravimetric network in Poland was established between 1994 and 1999. It is based on 12 points, so-called absolute points; the measurements on these points were done with five ballistic gravimeters: FG 5-101, FG 5-107, JILAg 5, IMGC and ZZG. Absolute points were selected, according to recommendations of the International Gravimetric Commission, on the lowest floors of such buildings, as observatories, museums, schools, churches, etc. It gives a chance, that the absolute point will survive for at least several decades. The paper includes the detailed descriptions of all absolute points. The measurements were performed by German, American, Finnish, Italian and Polish teams. As results of measurements, done with the use of various gravimeters, differed on a few points even by 30 microgals, it was necessary to make their verification. The direct connecting measurements between absolute points were performed with the use of four LaCoste & Romberg gravimeters. The measurements were done on 25 so-called long spans (160– 300 km). Results of absolute determinations and results of relative connections were jointly analysed. This analysis enabled to eliminate those gravimeters, which do not fulfil the assumed criteria of reliability – IMGC and ZZG. The remaining gravimeters: FG 5-101, FG 5-107 and JILAg 5, which did not differ in readouts more than 3 microgals, were found to be representatives of the international gravimetric standard. Their readouts were assumed as the standard for Polish gravimetric basic network. The results of relative measurements on 685 spans of network were adjusted to 12 absolute points and to 3 points on the territory of Germany. Finally set of values of gravity acceleration for 354 points of network was obtained. This network is homogeneous, as far as gravimetric level and gravimetric scale is concerned; it also fulfils accuracy and construction requirements.

2

Tatrzańska grawimetryczna baza kalibracyjna

100%

Cisak M. , Sas A.

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tom nr 1

12--15

3

Zmodernizowana podstawowa osnowa grawimetryczna kraju (POGK 97)

80%

Sas-Uhrynowski A. , Cisak M. , Sas A. , Siporski L.

Prace Instytutu Geodezji i Kartografii

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1999

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tom T. 46, z. 98

41--47

PL

Przedstawiono opis osnowy oraz szczegóły dotyczące prac pomiarowych na punktach osnowy, które były wykonane w latach 1994-1997.

EN

Basic gravimetric network of Poland was established in sixties, so now it does not fulfil the modern needs of geodesy, especially considering more common recent use of satellite measuring techniques. In 1977 the general project of modernisation of the network was prepared in the Institute of Geodesy and Cartography and approved by the Head Office of Geodesy and Cartography. All new points of the modernised gravimetric network were stabilised by concrete poles between 1978 and 1987, but the measurements were possible only in 1992, when the newest La Coste & Romberg gravimeters were purchased by the Institute of Geodesy and Cartography. Project of gravimetric network, verified by experts from the Geodesy Committee, Polish Academy of Sciences, was approved again by the Department of Surveyor General of Poland in 1993. New gravimetric network comprises fundamental point, located in the Observatory of the Institute of Geodesy and Cartography in Borowa Gora, which was already used several times to measure absolute acceleration of gravity, 16 absolute points (9 of which were already measured), 351 stabilised terrain points and two meridian’s calibration base lines, based on 6 absolute points. The Institute of Geodesy and Cartography started to measure the new network in 1994 and the measuring works were completed finally in 1997. Values of differences in acceleration of gravity Ag were calculated using scales of gravimeters determined on the basis of national gravimetric network, and next were re-calculated in 1997 to the system defined by absolute points. The whole network consists of 674 spans, where 722 measurements of differences in acceleration of gravity [delta]g were performed. It must be emphasised, that 62% of errors of Ag values measured on network spans does not exceed 0.010 mGal, while criterion of correctness is 0.020 mGal.

4

Vertical gravimetric calibration baseline in the Tatra Mountains of Poland

80%

Sas A. , Sas-Uhrynowski A. , Cisak M. , Siporski L.

Geoinformation Issues

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2009

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tom Vol. 1, no 1

19-32

EN

This article describes the establishment of an alpine gravimetric calibration baseline in Poland's Tatra Mountains and the development of a methodology for performing static gravimeter calibration on that baseline. This baseline was established in response to the recent rise in geodynamic research in mountainous areas and the related need to calibrate the gravimetric scale used in such gravimeter research to a high degree of accuracy. The fact that the environmental conditions of such an alpine gravimetric calibration baseline differ considerably from those observed in flat terrains made it necessary to study the impact which rapid changes in atmospheric pressure and environmental temperature may exert on the performance of gravimeters used in such survey. It was also important to study how the method by which the instruments were transported (by automobile, cable car, or on foot) affected their performance. The project led to the establishment of an alpine gravimetric calibration baseline and yielded a set of recommendations for how to proceed with scaling the gravimeters at such a baseline.

PL

Przedstawione prace związane są z założeniem górskiej grawimetrycznej bazy kalibracyjnej w Tatrach oraz opracowaniem metodyki przeprowadzania na niej kalibracji grawimetrów statycznych. Założenie takiej bazy wynika z nasilenia w ostatnich czasach badań geodynamicznych w górach i związaną z tym potrzebą ujednolicenia na wysokim poziomie dokładności skali grawimetrycznej, używanych do tych badań grawimetrów. Z uwagi na znaczące różnice warunków środowiskowych na bazie górskiej w porównaniu z tymi, jakie obserwuje się na bazach zakładanych w terenach płaskich, niezbędne było przeprowadzenie badań wpływu szybkich zmian ciśnienia atmosferycznego i temperatury otoczenia na pracę grawimetrów, które są używane w pracach pomiarowych. Niemniej ważne było zbadanie wpływu wykorzystywanego środka transportu (samochód, kolej linowa, ręczny transport instrumentów) na pracę instrumentów rodzaju. W wyniku przeprowadzonych prac utworzona została górska grawimetryczna baza kalibracyjna oraz podano zalecenia jak należy postępować przy skalowaniu grawimetrów na tej bazie.

5

A new gravimetric control network for Poland

70%

Sas-Uhrynowski A. , Cisak M. , Mroczek S. , Sas A. , Siporski L.

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tom z. 8/54

55-60