Tidal bundle Tidal bundle A tidal bundle is a sedimentary structure that forms in tidal areas as a result of spring and neap tides. A tidal bundle sequence can be seen as a variation in bed thickness with a periodicity of 14 days (diurnal) or 28 days (semidiurnal). During the neap tide, when the tidal current strength is weakest, smaller quantities of finer grains are deposited. As the tidal variation grows larger, towards the spring tide, larger quantities of coarser material will be deposited which results in an increasing bed thickness. Bed thickness will be greatest at the spring tide and then
Threats to sea turtles Fisheries often use large-scale nets and hook systems that are indiscriminate and catch whatever comes along, be it sea turtle, dolphin, or even shark. What is known as “bycatch” is a large contributor to sea turtle deaths, as seen in Baja California. Longline, trawl, and gillnet fishing are three types of fishing with the most sea turtle accidents. Deaths occur often because of drowning, where the sea turtle was ensnared and could not come up for air. Another dangerous aspect of fishing that is common is when sea turtles inadvertently swallow sharp hooks, which can get stuck within the soft