Dataset: M70/2a - Simrad EM120 Data | HOME Imprint |
Archive | DOI |
Dataset citation | HTML, BibTeX, RIS |
Metadata of dataset | ISO 19115/19139, FGDC, PANGAEA |
Cruise | M70/2a |
Navigation system | Meteor C-Nav |
Horizontal reference system (EPSG) | WGS84 geographic (4326) |
Sonar system | Simrad EM120 |
Sonar type | multibeam |
Depth definition | True depths |
Depth datum (EPSG) | MeanSeaLevel depth (5715) |
File format | Simrad multibeam processing format |
File listing | 291 files, as XML file |
Tracklength [km] | 1057 |
Generalised track ¹ | KML file |
Gross coverage [km²] (unedited - no warranty) | 4030 |
Usage | Primary data are generally not depth-edited and should not directly be used for final product compilations. |
Maintenance | Update frequency of dataset: notPlanned |
Constraints | Access: onDemand Use: copyright |
Status | completed |
Purpose | Eleven surveys were conducted in the three explored target areas: the eastern large mud volcanoes/gas chimneys (Amon and Isis), the central Nile pockmarks domain and the western Menes caldera. (in two Legs 70/2a and 70/2b) |
Abstract | The multibeam echosounder systems the SIMRAD EM120 was available on the R/V Meteor. During the BIONIL expedition, mainly the EM120 (operating at 12 kHz) was operated in the Nile Deep Sea Fan targets (800 to 3000 m water depths). Sound velocity profiles obtained during CTD operations (stations 764 and 767) were implemented for calibration. The vessel’s speed was ~ 5 kn during the surveys, and 10 kn during the transits. During BIONIL the main operational frequency was 12 kH, the maximum ping rate 5 Hz, the number of beams for each ping 191, the beam widths 1x2 or 2x2 degrees and the coverage sector 55° to 45° mostly, to increase the resolution The beam spacing is normally equidistant. In deep waters (~ >2000 m) a pulse length of 15 ms was used. The transmit fan is split into nine different sectors transmitted sequentially within the same ping. At intermediate depths a pulse length of 5 ms was used with the transmit fan split in three sectors. |
Sonar system operators | Gauger, Steffen |
(MaNIDA) data level | 0 |
Data quality / Lineage | |
Point of contact | MARUM bathymetry data responsible party |
Aggregation |
(¹): KML file is created online from database applying track generalization ±50 meter.