JRC ECDIS Instruction Manual page 318

Category name
(Local Magnetic Magnetic anomaly at a point
anomaly)
Magnetic anomaly along a
line or over an area
Magnetic variation at a point
Magnetic variation along a
line or over an area
(Natural Hill or mountain top
Feature/Seabed)
Conspicuous hill or mountain
top
Cable area
Foul area of seabed safe for
navigation but not for
anchoring
Sand waves
Spring
Weed, kelp
(Unknown) ? Mark
Generic Object
Appendix B Menu List and Materials
Object name
B-138
Icon button display
the own ship approaches
example
No alert
No alert
No alert
No alert
No alert
No alert
No alert
No alert
No alert
No alert
No alert
No alert
No alert
Alert generated when
the object