Journal of the Geodetic Society of Japan最新文献

{"title":"Reference Level Stability of the Canadian Superconducting Gravimeter Installation","authors":"J. Merriam, S. Pagiatakis, J. Liard","doi":"10.11366/SOKUCHI1954.47.417","DOIUrl":"https://doi.org/10.11366/SOKUCHI1954.47.417","url":null,"abstract":"The Canadian Superconducting Gravimeter Installation (CSGI) operates a GWR TT70 superconducting gravimeter at a site near Cantley, Quebec. An adjacent pier is the reference point for the Canadian Absolute Gravity Station (CAGS) JILA-2 absolute gravimeter. The co-location of the two instruments provides an opportunity to examine the drift of the superconducting gravimeter and to search for spurious signals in either instrument. It is known that the superconducting gravimeter suffers from occasional tares, but the extent to which there are spurious signals on any time-scale is unknown. Nine separate experiments have been conducted since February 1998, in which the absolute gravimeter was dedicated to rapid sampling of gravity for about a week. From these we have calibrated the superconducting gravimeter, established the drift, and assessed the level of spurious gravity signals in both instruments. The calibration factor recovered from these experiments is -78.3 +/0.1 microgal/V. During the period from early 1998 to late 1999, the superconducting gravimeter maintained a constant reference level to better than three microgals. However, in 1 early 2000, the level of the absolute gravimeter rapidly diverged from that of the superconducting gravimeter achieving a maximum recorded difference of fourteen microgal during April 12-13 2000. As of June 2000 the absolute gravimeter had recovered and the offset between the two is again only two microgal. There is occasionally a rough correlation between the (tide and pressure corrected) residuals of the two gravimeters at the microgal or better level on time-scales down to about a day. However, in several experiments no correlation was apparent and excursions of the absolute gravimeter of several microgal persisting for several hours were noted. Most of the variance of the absolute gravimeter residuals seems to be at periods of hours to a day, and there are occasionally episodes of several hours duration when the instrument reads low by several microgal. Introduction The co-location of an absolute gravimeter (AG) and a superconducting gravimeter (SG) is advantageous to both, because the SG offers rapid, precise samples of relative gravity while the AG delivers absolute gravity measurements although of less precision. Indeed, absolute gravimeters are often used to calibrate superconducting gravimeters (Hinderer et al, 1991), and superconducting gravimeters have been used to assess the precision of absolute gravimeters (Okubo et al, 1997). SG’s are subject to tares, or sudden offsets in reference level. These are routinely detected and repaired, but the only way of assessing the reliability of this procedure is by reference to an absolute gravimeter. Accumulated tares of about 14 μgal have been removed from the SG data used here. The small residual offset between AG and SG of ±3μgal suggests that the detection and correction procedure is working well. In this work, we examine the residuals of both AG and SG to tr","PeriodicalId":39875,"journal":{"name":"Journal of the Geodetic Society of Japan","volume":"47 1","pages":"417-423"},"PeriodicalIF":0.0,"publicationDate":"2001-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64262388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A New Method of Spectral Analysis Based on the Technique of the AM Receiver.","authors":"W. Morii","doi":"10.11366/SOKUCHI1954.47.294","DOIUrl":"https://doi.org/10.11366/SOKUCHI1954.47.294","url":null,"abstract":"","PeriodicalId":39875,"journal":{"name":"Journal of the Geodetic Society of Japan","volume":"47 1","pages":"294-299"},"PeriodicalIF":0.0,"publicationDate":"2001-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64260658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tidal Effects and Space Geodetic Techniques","authors":"R. Haas","doi":"10.11366/SOKUCHI1954.47.161","DOIUrl":"https://doi.org/10.11366/SOKUCHI1954.47.161","url":null,"abstract":"","PeriodicalId":39875,"journal":{"name":"Journal of the Geodetic Society of Japan","volume":"47 1","pages":"161-168"},"PeriodicalIF":0.0,"publicationDate":"2001-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11366/SOKUCHI1954.47.161","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64259716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tidal Strains Observed with Extensometers in Donzurubo Observatory, Nara, Japan","authors":"Kensuke Onoue, A. Mukai, S. Takemoto","doi":"10.11366/SOKUCHI1954.47.141","DOIUrl":"https://doi.org/10.11366/SOKUCHI1954.47.141","url":null,"abstract":"","PeriodicalId":39875,"journal":{"name":"Journal of the Geodetic Society of Japan","volume":"47 1","pages":"141-147"},"PeriodicalIF":0.0,"publicationDate":"2001-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11366/SOKUCHI1954.47.141","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64259850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Superconducting Gravimetry in Geophysical Research Today","authors":"B. Meurers","doi":"10.11366/SOKUCHI1954.47.300","DOIUrl":"https://doi.org/10.11366/SOKUCHI1954.47.300","url":null,"abstract":"","PeriodicalId":39875,"journal":{"name":"Journal of the Geodetic Society of Japan","volume":"47 1","pages":"300-307"},"PeriodicalIF":0.0,"publicationDate":"2001-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64261476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Spectral Comparison of Absolute and Superconducting Gravimeter Data","authors":"Crossley David, J. Hinderer, M. Amalvict","doi":"10.11366/SOKUCHI1954.47.373","DOIUrl":"https://doi.org/10.11366/SOKUCHI1954.47.373","url":null,"abstract":"","PeriodicalId":39875,"journal":{"name":"Journal of the Geodetic Society of Japan","volume":"28 1","pages":"373-379"},"PeriodicalIF":0.0,"publicationDate":"2001-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64261778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Calibration of a Superconducting Gravimeter with an Absolute Gravimeter FG-5 in Kyoto","authors":"S. Ogasawara, T. Higashi, Y. Fukuda, S. Takemoto","doi":"10.11366/SOKUCHI1954.47.404","DOIUrl":"https://doi.org/10.11366/SOKUCHI1954.47.404","url":null,"abstract":"","PeriodicalId":39875,"journal":{"name":"Journal of the Geodetic Society of Japan","volume":"184 1","pages":"404-409"},"PeriodicalIF":0.0,"publicationDate":"2001-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64262140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-term Observation of Tidal Variations of in Situ Seismic Velocity and Attenuation","authors":"K. Yamamura, O. Sano, H. Utada, Y. Fukao, S. Nakao, Y. Takei","doi":"10.11366/SOKUCHI1954.47.482","DOIUrl":"https://doi.org/10.11366/SOKUCHI1954.47.482","url":null,"abstract":"","PeriodicalId":39875,"journal":{"name":"Journal of the Geodetic Society of Japan","volume":"47 1","pages":"482-487"},"PeriodicalIF":0.0,"publicationDate":"2001-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64262903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Europa's Tides and Possible Hidden Liquid Ocean-With New Simulations on Different Orbit Configurations and Non-Global Ocean Basins","authors":"Xiaoping Wu, Y. Bar-Sever, W. Folkner, James G. Williams, J. Zumberge","doi":"10.11366/SOKUCHI1954.47.501","DOIUrl":"https://doi.org/10.11366/SOKUCHI1954.47.501","url":null,"abstract":"","PeriodicalId":39875,"journal":{"name":"Journal of the Geodetic Society of Japan","volume":"47 1","pages":"501-507"},"PeriodicalIF":0.0,"publicationDate":"2001-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64263081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of Long-term Gravity Variations, Based on Data of the GGP Co-operation","authors":"M. Harnisch, G. Harnisch","doi":"10.11366/SOKUCHI1954.47.322","DOIUrl":"https://doi.org/10.11366/SOKUCHI1954.47.322","url":null,"abstract":"Abstract The study continues a paper with the same title, presented at the Earth Tides Symposium 2000 in Mizusawa. Now data series from 12 GGP stations could be included (BE, BO, CA, CB, MB, MC, MO, PO, ST, SU, VI, WE). The length of the data series varies between 4 and 18 years. From some stations hydrological data were available. In most cases, the drift of the gravimeters was low and nearly linear. No absolute gravity measurements were available to support the estimation of the instrumental drift. Again the annual wave and the Chandler wobble were separated by fitting two sinusoidal functions with periods of 365.25 and 432 days to the residual gravity. As to be expected, the results for the individual stations move closer together and become more reliable. The δ-values of the Chandler wobble approach to 1.16. The correspondent values of the annual wobble are slightly smaller but demonstrate considerable variability. The phase lags of both phenomena are in the order of a few degrees.","PeriodicalId":39875,"journal":{"name":"Journal of the Geodetic Society of Japan","volume":"47 1","pages":"322-327"},"PeriodicalIF":0.0,"publicationDate":"2001-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64261160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}