Main
Menu
1. Welcome
2. The Idea
3. Boarding
4. Ship Tour
5. Back Deck
6. Preparing to Depart
7. Leaving
8. Meeting
9. Bay-Delta-Estuary
10. Navigating
11. The Survey
12. First Data
13. The Mosaic
14. Visualizing
15. Hazards
16. Disposal Site
17. Sediment Map
18. Compare
19. Future Studies
20. Final Meeting
Contact
Don Reed
Dept. of Geology
San José State
University
We will be working a “4 on and 8 off schedule, meaning that you will be in the science lab 4 hours, then off watch for eight hours, then back on for four hours, and off again, another eight hours – each day. A word to the wise …. it is good establish an orderly schedule for your sleeping and eating habits while at sea, so select one of your “eight hour off” periods for most of your sleep. Also, do not be late for your shift in the science lab, indeed arrive 5-10 minutes early in order to discuss the events of the previous shift with your co-workers. A smooth transition between shifts is essential to acquiring high quality data without interruption.
It is your lucky day, since you have been assigned the “best shifts – from 8 to 12 each day (8 am to 12 pm, and 8 pm to 12 am. Your fellow students will be assigned the 4-8 shift and the 0-4 shift.
Welcome everyone.
We are looking forward to an excellent and safe voyage. As you may know, our work will continue around the clock now that we have left port.
Let's hear from John about our duties on the voyage?
How will students work during the cruise?
But most importantly of all, will we get seasick?
Image
courtesy of USGSWe have three primary goals for this expedition,
(1) identify and assess potential hazards to navigation in the survey area,(2) assess the viability of the current dredge disposal site near Alcatraz, and(3) produce a map of the major features on the bay floor that can be used now and in the future in assessing the environmental impacts on the bay.To achieve these goals, we will collect a survey of about 45 square kilometers or approximately 17.5 square miles (45 km2) of the bay floor was using a multibeam sonar system.
This system will simultaneously acquire bathymetric and backscatter data. Bathymetry refers to the water depth and backscatter is the ability of the seafloor to scatter sound waves, often related to the texture (roughness) of the seafloor. In other words, we will produce a map of the water depth in the survey region, which will yield information about the shape of the bay floor (where is it deep and where is it shallow) and a map of the roughness of the bay floor, from which we can make predications of the characteristics of the bay floor, such as sediment type, that can later be tested by taking sediment samples. We will run tracklines of the ship with a very close spacing in order generate a continuous mosaic of the area. We have given the locations of these lines to the captain who will steer the ship based our GPS navigation.
Let's
hear about the formation of the San Francisco Bay-Delta-Estuary