We mapped 26 bays. Four charts are available for each bay covering bathymetry, backscatter and shaded relief.
Bathymetry is the study of underwater depth of our oceans, seas or lakes. It is measured using an Echosounder which uses sound waves to measure the depth. A transducer is mounted under the vessel and this emits a pulse which travels through the water, bounces against the seafloor and returns back to a receiver. The time it takes for the signal to return is calculated with the formula for the speed of sound through water and this determines the underwater depth.
Backscatter is a term used to determine seafloor types (e.g. mud, sand, rock etc.) based on the energy level of the returning signal. Different seafloor types return the signal with different levels of energy. Softer seafloors such as mud will return a weaker signal than a harder seafloor like rock.
Shaded Relief, or hill-shading, displays the shape of the terrain as a three-dimensional surface by the use of shadows cast from a point light source. Our charts provide Shaded Relief North East and Shaded Relief North West which give the effect that the sun is shining down from either a NE or NW direction.
Click here to locate your bay and download charts. Alternatively, discover your bay from the list below.