Gravimetric network: new perspectives of adjustment, quality analysis and gravimetric data integration
Abstract
International Gravity Standardization Net 1971 (IGSN71) it is at the
present time the world gravity network of reference. The national fundamental
gravity network and flowed they are usually established saw relative survey this
world network. Due to the brazilian territorial extension where only 20 places
exist with stations IGSN71 and the access difficulties to remote areas, the
precision of the networks flowed usually comes in the interval from 50 to 100
microgal. This conception of gravity survey became modified, with constraining
of observations of differences gravity in the existent networks for control and
readjustment, with the calibration of gravimeters in field and the control of the
factor of instrumental scale. With base in those ideas initials, it was conceived a
Scientific Gravity Network for the State of Paraná. In the present work the
conceptions, strategies and experimental activities associated to the
methodology of implantation of gravity networks of high precision in Brazil are
presented. For so much, a network was implanted with stations in 21 places of
the State of Paraná and one in the State of São Paulo. The survey of the
observations was made with four gravimeters, three of the type LaCoste &
Romberg, models G-114, G-143, G-372 and a digital gravimeter Scintrex,
model CG3. Combining the observations with four gravimeters with the
adjustment strategies for the method of least square employed for network, were
obtained several solutions for the network. It is also presented a criterion for
integration of observations LaCoste & Romberg with observations originating
from of the gravimeter Scintrex. For analysis of all the obtained solutions, as
well as the decision for the great solution, the criteria of precision and reliability
were used for geodetic networks.
present time the world gravity network of reference. The national fundamental
gravity network and flowed they are usually established saw relative survey this
world network. Due to the brazilian territorial extension where only 20 places
exist with stations IGSN71 and the access difficulties to remote areas, the
precision of the networks flowed usually comes in the interval from 50 to 100
microgal. This conception of gravity survey became modified, with constraining
of observations of differences gravity in the existent networks for control and
readjustment, with the calibration of gravimeters in field and the control of the
factor of instrumental scale. With base in those ideas initials, it was conceived a
Scientific Gravity Network for the State of Paraná. In the present work the
conceptions, strategies and experimental activities associated to the
methodology of implantation of gravity networks of high precision in Brazil are
presented. For so much, a network was implanted with stations in 21 places of
the State of Paraná and one in the State of São Paulo. The survey of the
observations was made with four gravimeters, three of the type LaCoste &
Romberg, models G-114, G-143, G-372 and a digital gravimeter Scintrex,
model CG3. Combining the observations with four gravimeters with the
adjustment strategies for the method of least square employed for network, were
obtained several solutions for the network. It is also presented a criterion for
integration of observations LaCoste & Romberg with observations originating
from of the gravimeter Scintrex. For analysis of all the obtained solutions, as
well as the decision for the great solution, the criteria of precision and reliability
were used for geodetic networks.
