Ralf Krocker, Karsten Gohl 2007-02 gzip compressed, space delimited ASCII file http://dx.doi.org/10.1594/PANGAEA.602286 Gravity The gravimetric measurements have been executed during R.V. POLARSTERN cruise ANT-XII/4. The used gravity sensor was a KSS31 of Bodenseewerk Überlingen, Germany. The additional measurements for gravimetric datum shift have been executed using a Lacoste/Romberg gravity meter. Referenced gravity fix points are located in Rothera, Base Station (Adelide Island) and Punta Arenas, Centro Administratum del Puerto (Chile). Positions have been measured by three GPS-antennas, which were installed as a triangle to determine ships orientation and rotation angles as well. Positions have been corrected by SKYFIX provided 'Wide Area Differential GPS' (WADGPS) data. Heading was measured by gyro. Simple Bougueranomalies have been calculated by reducing Bouguerplate with density of 2.67 g/cm^3 (and density contrast of 1.64 g/cm^3 respectively). Used bathymetry has been sampled with swath sonar system Hydrosweep DS2 and is also be published in PANGAEA database. Missing data are represented by 999999.0 (gravity) and 0.0 (bathymetry). The gravimetric measurements have been sampled to support geophysical and geological interpretations of Peter I. Island, DeGerlache Seamounts and the Eltanin Impact Area during R.V. POLARSTERN cruise ANT-XII/4. Gravimetry has also been accomplished to expand existing datasets. None en 1995-03-20 01:05:43 1995-05-11 22:51:20 2007-02-05 Complete None planned -98.0516 -68.0745 -50.1379 -70.5172 None Gravity Eltanin Impact Meteorite Crater None South Pacific Bellinghausen Sea Peter I Island DeGerlache Seamounts Eltanin Impact Area None None. Acknowlegdement of the Alfred Wegener Institute would be appreciated in products derived from these data. Wilfried Jokat Alfred Wegener Institute for Polar and Marine Research mailing address

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Bremerhaven Bremen 27515 Germany (+49)471-4831-1211 (+49)471-4831-1926 Wilfried.Jokat@awi.de email is the preferred contact None Unclassified None Microsoft Windows 2000 Version 5.0 (Build 2195) Service Pack 4 Space delimited ASCII file Gravity measurements have been executed by Sea Gravity Meter KSS31 of Bodenseewerk Überlingen, Germany. Accuracy of anomalies amounts to 1 mgal. 1 Accuracy refers to filtered anomalies, but not to single datapoints. Filtering should be done in dependence of the waterdepth and resulting attenuation of gravity signal. complete Positions are measured by three GPS antennas installed as a triangle to determine ships orientation and rotation as well. Accuracy of Positions amounts to +-10 meters. Gravity data have been merged with navigational and bathymetric data relating to time. 2001 Datum Shift has been applied in relation to gravity fix points of Rothera, Base Station (Adelide Island) and Punta Arenas, Centro Administratum del Puerto (Chile) 2001 Eötvös-corrections have been applied 2001 Free Air Anomalies have been calculated by subtracting normal gravity of GRS80 2001 Simple Bougueranomalies have been calculated by reducing a Bouguer Plate with density of 2.67 g/cm^3 (and density contrast of 1.64 g/cm^3 respectively) 2001 Data have been reformatted into space delimited ASCII files, containing a time periode of 24 hours each. Irregular sampling interval has been kept and not been interpolated. 2007 Datasampling has been done along ship track. Therefore it is irregular in space Point String 377392 0.00001 0.00001 Decimal Degrees WGS84 6378137 298.25722 Gravity Identifier AWI internal Polarstern cruise identifier Author This attribute is always the same within one cruise 8 Date UTC date string (YYYY/MM/DD) GPS-Time 10 Time UTC time string: (hh:mm:ss) GPS-Time 10 Latitude Geographical coordinate in decimal degrees Wide Area Differential GPS. Nav-System: ANP2000 decimal degrees 9 Longitude Geographical coordinate Wide Area Differential GPS. Nav-System: ANP2000 decimal degrees 10 Depth Sea floor depth measured by Swath Sonar System Hydrosweep DS2 HYDROSWEEP DS2 -6398 -101 meter 7 FreeAirAnomaly Anomaly related to GRS80 Author -178.2 256.8 milligal 9 BouguerAnomaly Bouguer plate correction with density contrast between crust and water of 1.64 g/cm^3 Author -34.2 416.5 milligal 9 Wilfried Jokat Alfred Wegener Institute for Polar and Marine Research mailing address

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Bremerhaven Bremen 27515 Germany (+49)471-4831-1211 (+49)471-4831-1926 Wilfried.Jokat@awi.de None 1 2007-01-31 gzip 4.302.730 No fees for digital files 2007-02-06 Ralf Krocker Alfred Wegener Institute for Polar and Marine Research mailing address

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Bremerhaven Bremen 27515 Germany (+49)471-4831-1226 (+49)471-4831-1977 infobathy@awi-bremerhaven.de FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998 en