Contemporary crustal movements in Canada

1979 ◽  
Vol 16 (3) ◽  
pp. 647-668 ◽  
Author(s):  
A. Lambert ◽  
P. Vaníček
Keyword(s):  
Water Level ◽  
Vertical Movement ◽  
Local Deformation ◽  
Research Activity ◽  
Regional Pattern ◽  
Vertical Movements ◽  
Level Data ◽  
Water Level Data ◽  
Well Water Level ◽  
Viscoelastic Modelling

Our present knowledge of the patterns and causes of contemporary aseismic movements of the crust in Canada is reviewed. Modern and paleo water-level data and geodetic relevelling data are being used to delineate the regional pattern of vertical movements, but equivalent data on regional horizontal movements are not yet available. The first steps are being taken to relate the emerging regional pattern of vertical movement in Canada to the interactions on the western margin of the America plate and to the spatial variations in seismicity, gravity field, and crustal stress in the plate interior. Viscoelastic modelling of the earth's response to surface loads, and laboratory-based results on possible non-linear rheologies in the mantle have provided a useful theoretical framework for comparing new data on ice-sheet histories with paleo water-level results. Local-scale crustal deformations are being monitored by triangulation, levelling, and gravity networks, as well as by tiltmeters, strainmeters and well-water-level meters. The interpretation of the local deformation data has been facilitated by modelling of the response of inhomogencous-elastic and porous-elastic media. The level of research activity on local aseismic movements in different areas of Canada corresponds to the seismotectonic significance of the areas.

Determination of Survey Boat “Heave” Motion with the Use of RTS Technique

2017 ◽  
Author(s):  
Dariusz Popielarczyk
Keyword(s):  
Water Level ◽  
Vertical Movement ◽  
Bathymetric Survey ◽  
Total Station ◽  
Vistula River ◽  
Level Data ◽  
Water Level Data ◽  
Hydroacoustic Measurements ◽  
Heave Motion

The paper presents analysis of determination of vertical movement of the surveying boat called “heave” with the use of Robotized Total Station (RTS) technique. The classical geodetic Total Station was used for sub-centimeter calculation of water level changes during hydroacoustic measurements on the fragment of Vistula river behind the dam and hydropower in Włocławek in Poland. The power station work causes up to 1.7 m movement of vertical reference water surface in aspect of local bathymetric survey. The experimental, hydrographic surveys on the river were conducted where the water level was changing significantly over time depending on the operational schedule of the power plant. Verified hydrographic data had to be brought to the common water level. To determine the final water level, data on the height of the Robotized Total Station prism positioned on the boat during sounding was considered. The RTS technique with 0.02–0.05 m vertical accuracy proved to be very useful and essential in engineering inland bathymetric measurements.

Presentation and assessment of tides and water level records for geophysical investigations

1970 ◽  
Vol 7 (2) ◽  
pp. 607-625 ◽  
Author(s):  
G. C. Dohler ◽  
L. F. Ku
Keyword(s):  
Water Level ◽  
Power Spectra ◽  
Rate Of Change ◽  
Regression Technique ◽  
Level Data ◽  
Water Level Data ◽  
Geophysical Investigations ◽  
Water Level Variations ◽  
Mean Water Level ◽  
Change In Mean

The methods and problems involved in collecting water level data are explained, and the processing and formats of the data are illustrated. The trend of the change in mean water level is plotted and the corresponding rate of change is estimated by the regression technique. The power spectra of the water level variations are plotted to illustrate these variations in terms of frequencies.

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