Dataset: M70/2a - Simrad EM120 Data

HOME 
Imprint 
Archive DOI
Dataset citation HTML, BibTeX, RIS
Metadata of dataset ISO 19115/19139, FGDC, PANGAEA
CruiseM70/2a
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 listing291 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.