... Title : Absolute Gravity Measurements with Reversible Pendulums at Potsdam, 1968-1969 (Absolute Schwaremessungen mit Reversionpendein in ...

... absolutely; and second, equal-spectrum filtering, where the ... GRAVITY, MEASUREMENT), GEODESICS, ELECTRIC FILTERS, LEAST SQUARES ...

The status of absolute gravimetry is discussed. An easily portable apparatus for the absolute determination of the acceleration of gravity is described. Laboratory tests of this instrument indicate that a measurement accuracy of six parts in a billion is achieved. This corresponds to an equivalent height ...

... Valley Caldera, Mono County, California, 1985, USGS Water Resources Investiga ... and A. Ryall, Active tectonic and magmatic processes beneath ...

The major activities of U.S. governmental organization in land gravimetry are reviewed. The NGS, NOAA, USGS, DOE, NRC, DoD, and AFGL work is included, and recent developments provided accurate portable absolute gravity measurement devices, new gravity surveys and anomaly maps, and a helicopter ...

The A10 is the first outdoor absolute gravimeter that allows for the determination of gravity with high precision. Absolute gravity survey with the A10 becomes highly competitive in terms of both efficiency and precision with traditional relative gravity survey. The portable A10-20 ...

In the 11 years since PMFC-1, a number of new techniques have been put into practice in the Air Force Geophysics Laboratory's transportable system for measuring the acceleration of gravity. The improved system in use at the present time incorporates an ea...

This paper discusses simultaneous gravity and vertical gravity gradient measurements obtained with a newly designed recoil-compensated dropping chamber adapted to an FG5 absolute gravimeter. The new dropping chamber incorporates counterweights to compensate recoil effects. It has the same physical length as the ...

... Title : Some Geophysical Consequences of the New High-Precision Method of Absolute Gravity Measurement (Quelques Consequences ...

instruments to measure total solar irradiance (TSI) with the absolute ... SPACE > SOLAR REGION > PHOTOSPHERE. Science Keywords. AGRICULTURE > AGRICULTURAL ...

instruments to measure total solar irradiance (TSI) with the absolute radiometers DIARAD and PMO6V, spectral solar ... GEOSCIENTIFIC INFORMATION FARMING ...

A new absolute determination of the acceleration due to gravity was made at the former Geodatisches Institut Potsdam (since 1969 part of the Zentralinstitut Physik der Erde), using the reversible pendulum method. Beside essential theoretical fundamentals ...

Repeatable high-precision gravity surveys provide a method of monitoring temporal variations in the gravity field. Fluctuations in the gravity field may indicate water table changes, crustal deformation, or precursors to volcanism and earthquakes. This report describes a high-precision gravity loop which has been ...

The Rural Watershed Initiative, established by the State of Arizona, was formed to address water-supply issues in areas outside the State's more populous regions, with an emphasis on regional watershed studies. In cooperation with the Arizona Department of Water Resources, the U.S. Geological Survey is conducting a number of hydrogeologic investigations under this initiative. This work has ...

... ADA286670. Title : Absolute Determination of the Acceleration of Gravity at the All-Union Scientific Research Institute of Metrology,. ...

AGTO is a scientific project between Taiwanese and French institutes which aim is to improve tectonic knowledge of Taiwan primarily using absolute gravity measurements and permanent GPS stations. Both tools are indeed useful to study vertical movements and mass transfers involved in mountain building, a major process in Taiwan located ...

Since 2001, the absolute gravimeter FG5#215 has been used for modernization of national gravity networks in Czech Republic, Slovakia and Hungary. Altogether 37 absolute sites were measured at least once. In case of 29 sites, the absolute gravity has been determined prior to ...

Absolute gravity measurements over nearly a decade at 10 field sites in North America have provided insights on a range of phenomena from tides to postglacial rebound. In this overview we demonstrate the potential of long-term, terrestrial gravity measurements at selected sites to assist in the ...

In this study we attempt to understand the water storage variations in a karst aquifer on the Larzac Plateau (South of France) using ground-based gravimetry. Surface to 60 m depth gravity measurements are performed three times a year since 2006 down a pothole, in complement to monthly absolute gravity (AG) ...

The Canadian Gravity Standardization Net (CGSN), a network of primary and secondary gravity sites, provides the reference linkage for regional and local gravity surveys performed in different places and at different epochs in Canada. Maintained over the last five decades, CSGN has produced a reliable determination of the gravitational ...

Experimental realizations of cold 85Rb atom interferometers in Wuhan are reviewed in this paper. The application of atom interferometers in local gravity measurement are reported. The resolutions of gravity measurement are 2.0 � 10-7g for 1 s and 4.5 � 10-9g for 1,888 s. The absolute g ...

In 1990, the National Institute of Standards and Technology (NIST), the National Oceanic and Atmospheric Administration (NOAA), and the Institute for Applied Geodesy (IFAG), Germany, joined forces to produce a gravity meter better suited to transportation and field operations and capable of providing more stringent data constraints on geophysical theory. The result is the AXIS ...

One of the products derived from the gravity field and steady-state ocean circulation explorer (GOCE) observations are the gravity gradients. These gravity gradients are provided in the gradiometer reference frame (GRF) and are calibrated in-flight using satellite shaking and star sensor data. To use these gravity ...

A gravity base network is supposed to be a set of benchmarks uniformly distributed across the country and the absolute gravity values at the benchmarks are known to the best accessible accuracy. The gravity at the benchmark stations are either measured directly with ...

One of the products derived from the GOCE observations are the gravity gradients. These gravity gradients are provided in the Gradiometer Reference Frame (GRF) and are calibrated in-flight using satellite shaking and star sensor data. In order to use these gravity gradients for application in Earth sciences and ...

The aim of this study is to develop methods that clarified the systematic relations between vertical movements and mass changes by the help of absolute and relative gravity measurements as well as GPS observations. Using these relations, the anomalies about the vertical crustal deformation in the Marmara Region will be determined and ...

The Nordic countries Norway, Sweden, Finland and Denmark are a key study region for research of glacial isostasy. In addition, such research offers a unique opportunity for absolute gravimetry to show its capability as a geodetic tool for geophysical research. Within a multi-national cooperation, annual absolute gravity ...

In an absolute gravity meter, a laser interferometer measures the position of a test mass that is falling ina vacuum. The calculated value of gravity is the average acceleration of the mass during a set ofdrops. Since systematic accelerations of the optical system will bias the measured value ...

For the past 300 years, southeastern Alaska has undergone rapid ice-melting and land uplift attributable to global warming. Corresponding crustal deformation (3 cm/yr) caused by the Little Ice Age retreat is detectable with modern geodetic techniques such as GPS and tidal gauge measurements. Geodetic deformation provides useful information for assessing ice-melting rates, ...

In June 1987 a gravimeter calibration range was set up in southeastern Alaska and the Yukon territory, as part of a geophysical determination of the Newtonian gravitational constant. Absolute gravity measurements were made between the range endpoints using the Institute of Geophysics and Planetary Physics absolute ...

Gravity monitoring provides a cost-effective means of monitoring subsurface mass changes of engineering interest. In July to October 2003, we conducted a gravity monitoring study of canal infiltration in the Dutch Flats irrigated farming area of western Nebraska, USA. An unlined east-west canal on the north edge of the monitoring network leaks southward ...

We will provide some answers to the following frequently asked questions regarding gravity gradiometry: Given that gravity, gravity gradients, and geoid measurements are all derived from the identical gravity potential what is the benefit of one kind of measurement over ...

AGTO is a scientific project between Taiwanese and French institutes, which aim is to improve tectonic knowledge of Taiwan primarily using absolute gravity measurements and permanent GPS stations. Both tools are indeed useful to study vertical movements and mass transfers involved in mountain building, a major process in Taiwan located ...

One of the objectives of the GRACE mission is the monitoring of temporal changes in water mass distribution on the continents. To a first approximation, variations in the mean water content and the corresponding gravity signal can be expressed as a seasonal variation and a trend. We compare GRACE seasonal gravity variations with seasonal surface ...

It is recognized widely nowadays that the superconducting gravimeter (SG) is a kind of best relative gravimeter with high observing precision, good continuity and stability. However, it is necessary to calibrate the direct output (change in voltage) by using scale value (calibration factor) before getting the change of the real gravity field. Studies show that the accuracy of ...

Materials within the Himalaya are rising due to convergence between India and Asia. If the rate of erosion is comparable to the rate of uplift, the mean surface elevation will remain constant. Any slight imbalance in these two processes will lead to growth or attrition of the Himalaya. Although buried rocks, minerals and surface control points in the Himalaya are undoubtably rising, the growth or ...

... Title : Characteristic Functional of a Probability Measure Absolutely Continuous with Respect to a Gaussian Radon Measure. ...

Absolute gravity measurements are based on the reconstruction of the free-falling motion of a test body in vacuum. In this paper, two large disturbing effects are studied, namely the non-gravitational accelerations originated by rotation and translation of the flying body. Their contribution to the uncertainty of the free-fall ...

Time can never be measured directly. Time is calculated from changed lengths and angles by using all clocks. In addition, an atomic absolute clock and an atomic absolute telemeter have a contradictory relation to depend on each other. Of course, there is no absolute time. The time of all clocks are changed by ...

The Taiwan mountain belt results from the collision between Philippine Sea and Eurasian plates. Taiwan island experiences high tectonic deformation due to fast convergence between the two plates. It has been and is still widely studied and is often considered as a natural laboratory for orogeny studies. Since 2006, the French-Taiwanese scientific project AGTO (Absolute ...

Finland belongs to the Fennoscandian postglacial rebound (PGR) area, with vertical velocities of up to 1 cm/yr and corresponding surface gravity rates as large as -2 microgal/yr. Knowledge of the secular gravity change in Finland comes so far from three sources: (i) repeated absolute gravity ...

To clarify effects of gravity on the water vapor exchange between plants and the ambient air, we evaluated the transpiration rate of plant leaves at 0.01, 1.0, and 2.0 g for 20 s each during parabolic airplane flights. The transpiration rates of a strawberry leaf and a replica leaf made of wet cloth were determined using a chamber method with humidity sensors. ...

The Bureau International des Poids et Mesures (BIPM), S�vres, France, hosted the 7th International Comparison of Absolute Gravimeters (ICAG) and the associated Relative Gravity Campaign (RGC) from August to September 2005. ICAG 2005 was prepared and performed as a metrological pilot study, which aimed: To determine the gravity ...

The MSTAR sensor (Modulation Sideband Technology for Absolute Ranging) is a new system for measuring

... Accession Number : AD0616613. Title : AN ABSOLUTE MEASUREMENT OF THERMAL NEUTRON ALBEDO FOR SEVERAL MATERIALS. ...

... CURRENT UNDERSTANDING OF THE ABSOLUTE MEASUREMENTS OF THE AMOUNT, FREQUENCY SPECTRA, AND WAVE FORMS OF THE ...

... for Absolute Measurements at the ... of a Lyman-alpha photometer on ... MAGNETOSPHERE, ULTRAVIOLET RADIATION), SCIENTIFIC SATELLITES ...

Developments in geodetic instrumentation during 1975 through 1978 are reviewed. Distance measurement including electronic distance measuring (EDM) application and instrumentation; the improvement of astronomic latitude and longitude determinations by the development of Automated Astronomic Positioning System and an instrument capable of ...

The southeast Alaska is undergoing a rapid ice-melting and land uplift due to the effect of global warming in the last three hundred years. The corresponding crustal deformation caused by the post-glacial rebound has been clearly detected by modern geodetic techniques, e.g., GPS and tidal gauge measurements (Larsen et al., 2004; Sato et al., 2005). The geodetic deformation ...

In order to model the earth gravity field and its temporal variations, different gravity data with terrestrial, airborne and satellite gathered kinds are necessary. It is possible to recover by them the short, medium and long wavelengths of the gravity field respectively. Terrestrial gravity data, especially for ...

In urbanized areas, one of the urgent problems is to monitor the groundwater variations especially connected with land subsidence. Although the groundwater variations are usually measured by water level meters, gravity measurements can provide us additional information about the water mass movements which should be beneficial for the ...

The MPG-2 (Max-Planck-Gravimeter) is a transportable absolute gravimeter built on a classical free-fall scheme to measure the local gravity value. With significant improvements and further investigations in recent years, the standard deviation of the mean for a typical measurement over 12 h to 24 h is 1.0 �Gal to ...

A unified field theory is established by allowing the expansion of spacetime to occur incrementally, according to a very specific multidimensional geometry. The ``quantum sized'' integration of spacetime upon the existing structure of reality produces a disturbance resulting in the observed probabilistic effects associated with Quantum Mechanics. The geometry of the expansion produces the physical ...

There is growing interest in the use of gravity methods to monitor changes in subsurface water storage and to use these data to infer aquifer hydraulic properties. The gravity method is not new; but, there is renewed interest in the potential of the method for hydrologic investigations due to improvements in the measurement ...

Repeat observations of the absolute acceleration of gravity have been made routinely at 16 gravity monitoring stations in central and southern Arizona since 1998. The observations are gravity control for repeat relative- gravity surveys of networks of stations that monitor aquifer-storage ...

Gravity meters have long been used to gain static information about the earth. For example, gravity provides information about the shape of the earth for geodetic purposes as well as subsurface density anomalies that can be used to locate oil, gas, and other minerals. Gravity is also very sensitive to vibrations in the earth induced in ...

The Nouveau Quebec-Labrador region was the site of one of the major ice domes of the Laurentide Ice Sheet and is currently experiencing postglacial rebound. Geodetic data provide a useful and accurate method of measuring the pattern and rates of contemporary uplift in this region. In order to monitor the temporal variations in gravitational potential resulting from regional ...

In this study we attempt to understand the water storage variations in a karst aquifer on the Larzac Plateau (South of France) using ground-based gravimetry. Surface to 60 m depth gravity measurements are performed three times a year since 2006 down a pothole, in complement to monthly absolute gravity (AG) ...

Relative high-precision measurements to detect the change in gravity differences due to the Fennoscandian Postglacial Rebound (PGR) were started in 1966 on an east-west line at the latitude 63�N in Finland (Kiviniemi, 1974). In 1967 the line was extended to Sweden and Norway by Rikets Allm�nna Kartverk (now Lantm�teriet, Sweden) and Norges ...

The primary role of the Geodetic Survey Division (GSD) is to maintain, continuously improve, and facilitate efficient access to the Canadian Spatial Reference System (CSRS). This includes the responsibility to maintain the Canadian Gravity Standardization Net (CGSN) that provides datum control for gravity observations across Canada. The current primary ...

Crustal uplift and relative sea-level (rsl) rise along the northern Cascadia margin, from Washington State to northern Vancouver Island, are related to ongoing subduction and Holocene post-glacial rebound. A joint analysis of absolute gravity, GPS, and tide gauge data should, in theory, constrain regional sea-level rise and vertical crustal movement, as ...

To observe secular land movements of the order of a few millimetres per year, a very precise instrument with long-term stability is required. This can be achieved using absolute gravimeters, which do not depend on a reference frame. Vertical land movements would modify the gravity at a rate of about -10 nms-2 (1 ? Gal) for 5 mm of uplift. Repeated ...

... Title : GRAVITY MEASUREMENTS OVER THE EUROPEAN CALIBRATION LINE WITH LACOSTE AND ROMBERG GRAVITY METERS G-2, G-5 ...

GRAVITY DEFORMATION MEASUREMENTS. OF 70m REFLECTOR SURFACES. Michael Brenner ... five elevation angles so that a gravity deformation model ...

Repeat measurements of absolute gravity have been made since 1998 to estimate changes in ground-water mass as part of ground-water budget estimates in arid and semiarid regions of the Southwestern United States. The absolute acceleration of gravity is measured twice each ...

Since 2007, in a collaboration between the Ohio State University, the Luxembourg University and DTU Space (Technical University of Denmark), have a number of permanent GPS stations been deployed in Greenland in a project called GNET (Greenland Network). These autonomous stations are placed all around the Greenland ice sheet and placed on the ice-free bedrock. At the present, 45 stations have been ...

Absolute gravity measurements in the Fennoscandian postglacial rebound area started already in 1976 when a team from Istituto di Metrolog�a "G. Colonnetti" (Torino) measured six stations with the rise-and-fall gravimeter IMGC (Cannizzo et al., 1978). In 1980 two stations were measured by the ...

... Title : EXTENSION OF ABSOLUTE FREQUENCY MEASUREMENTS TO 148 THZ: FREQUENCIES OF THE 20- AND 35- MICRONS XE LASER, IN ...

... Accession Number : AD0178854. Title : ABSOLUTE CAPACITANCE MICROCREEP AND DIMENSIONAL STABILITY MEASURING SYSTEM. ...

Gravity data from the superconducting gravimeter (GWR C039) at Ny-� lesund, Svalbard, Norway, have been analysed for long periodic variations. Prior to the analysis the gravity data was filtered and cleaned, by removing e.g. earthquakes and spikes. Any drift in the SCG data was removed using available absolute ...

... Absolute Measurement of Sound Pressure in Liquids. ... of Plane, Finite Amplitude Waves in a ... Optical Method for Ultrasonic Velocity Measurements at ...

... (Author). Descriptors : (*GRAVITY, *ALASKA), MEASUREMENT, VOLCANOES, DRIFT. Subject Categories : GEODESY. ...

... Title : CAMBRIDGE PENDULUM MEASUREMENTS OF GRAVITY DIFFERENCES ON THE WEST PACIFIC CALIBRATION LINE. ...

High-precision absolute gravity (AG) observations are sensitive to vertical motion of the observation site as well as mass redistribution within (and below) the underlying, slowly-deforming crust. The deformation gravity gradient (DGG) may be defined as the ratio of the time rate of change of surface gravity ...

The Phase 1 project focused on the development of a multiwave interferometer to measure absolute distance. Its applications are in gauging and for measuring absolute position of machine tools, and coordinate measuring machines. This interferometer overcom...

In continental plate interiors, ground surface movements are at the limit of the noise level and close to or below the accuracy of current geodetic techniques. Absolute gravity measurements are valuable to quantify slow vertical movements, as this instrument is drift free and, unlike GPS, independent of the terrestrial reference frame. ...

High-precision absolute gravity (AG) observations are sensitive to vertical motion of the observation site as well as mass redistribution within (and below) the underlying, slowly-deforming crust. On southern Vancouver Island, situated in the northern Cascadia forearc, long-term absolute gravity ...

addition, airborne gravity or gradiometry combined with GPS tracking can be applied to specific areasof interest. Absolute gravity measurementsare important ...

We present a numerical method, based on a FEM simulation, for the determination of the gravitational field generated by massive objects, whatever geometry and space mass density they have. The method was applied for the determination of the self-gravity effect of an absolute cold atom gravimeter which aims at a relative uncertainty of 10-9. The deduced ...

Hydrological time-varying processes (soil moisture, aquifers) redistribute underground water and hence lead to alter the gravity and shape of the Earth at various length scales (from very local effects to continental size) because of Newtonian attraction and elastic loading. We present here a new experiment set up in 2008 in West Africa called GHYRAF ...

The National Geodetic Survey absolute gravity program will utilize the high precision afforded by the JILAG-4 instrument to support geodetic and geophysical research, which involves studies of vertical motions, identification and modeling of other tempora...

The Nouveau Quebec-Labrador region was the site of one of the major ice domes of the Laurentide Ice Sheet and is currently experiencing postglacial rebound. For this region the highest observed uplift rates are in the vicinity of James Bay through to southwestern Labrador; the rates then decrease to the south and towards the coastal Atlantic margins. High-precision geodetic observations are ...

A total of 96 absolute gravity (AG) measurements at the Membach station and 221 at the Proudman Oceanographic Laboratory (POL) is analyzed for noise content. The lengths of the series were around 10 years (POL) and 8 years (Membach). First the noise at frequencies lower than 1 cpd is studied. This noise consists in setup-dependent ...

Measurements of the variation of gravity with depth in mines and boreholes permit the densities of intervening rock strata to be inferred. In the few cases in which reliable absolute values of density have been independently determined, the calculations can be used to check the value of the newtonian gravitational constant, G. Such ...

In continental plate interiors, tectonic deformations are small and the associated ground surface movements remain close to or below the accuracy of current geodetic techniques, and at the limit of the noise level. An absolute gravimeter is an appropriate tool to quantify slow vertical movements, as this instrument, based on length and time standards, is drift free and does ...

Weekday NEWS ARCHIVE TOPICS FORUM PHOTOS LINKS Web www.universetoday. com Coldest Temperature Ever Created). At absolute zero (-273?Celsius or - 460?Fahrenheit), all motion stops, except for tiny atomic vibrations in precision measurements by allowing better atomic clocks and sensors for gravity and rotation," said Dr

Comparison of gravimeters relative to absolute measurements is frequently used method for determination of gravimeters scale factors. This technique as completely non-invasive is especially important in periodic control of continuously recording gravimeters. We used almost 40 repeated parallel observations of LaCoste&Romberg spring gravimeter with FG5 ...

The direct problem of the detection of the Earth's absolute gravitation potential maximum value (MGP) was solved. The inverse problem finding of the Earth maximum gravitation (where there is a maximum of gravitation field intensity and a potential function has a 'bending point') with the help of MGP was solved as well. The obtained results show that the revealed Earth maximum ...

... Accession Number : ADA132199. Title : The JILA (Joint Institute for Laboratory Astrophysics) Portable Absolute Gravity Apparatus,. ...

... the establishment. (Total red blood cell product volume = weight of the RBC divided by the appropriate specific gravity. Absolute ...

A10 (Micro-G LaCoste Inc.) is a field absolute gravimeter which can be used for a variety of applications. Mainly for the studies of groundwater variation, land subsidence, geothermal fluid monitoring and so on, we introduced A10-17 in 2007. Since then, we have been conducting several test measurements not only to confirm the accuracy of the instrument but ...