There are several tools used to sample the ocean bottom and collect geological and biological data. These include grabs, dredges, trawls, cores, sieves, and remotely operated vehicles that can collect sediment and organism samples without direct human contact. Submersibles and autonomous underwater vehicles can explore deeper ocean depths for scientific research. Satellites are also used to map the ocean floor from above through gravity measurements and sonar imaging.

1. GEOLOGICAL OCEANOGRAPHIC RESEARCH EQUIPMENT

2. Sampling the Ocean Bottom Used to determine: sediment type and size organisms historical data

3. Sampling the Ocean Bottom Must assume that a small amount of material is representative of the larger area Therefore, must take as many samples as time and money allow

4. Grab or Clamshell Grab like a crane with jaws to grab sediment & organisms

5. Grab

6. Grab works differently in different seds soft seds – sinks deeper hard seds – does not grab as much

7. Dredge Collects materials from ocean bottom Often used to clear channels for navigation - Sometimes to collect organisms

8. Types of dredges: Dredge clam shell dredge

9. Types of dredges: Dredge suction dredge

10. scallop dredge backhoe dredge Types of dredges: Dredge

11. Trawl net dragged behind boat at various depths or along bottom

12. Trawl

13. trawl tracks can damage ocean bottom Trawl

14. Epibenthic Sled drag along bottom – like dredge can collect samples can house equipment

15. Core or Piston Core drill to collect a long tube of sediment

16. Core good for analyzing historic changes over long periods of time

17. Sediment Sieves used to sort sediments into their different sizes and find organisms living in the sediment

18. SCUBA s elf- c ontained u nderwater b reathing a pparatus allows person to see and sample limited time on bottom limited depth – about 100 feet

19. Submersible Alvin small research submarine

20. Submersible Johnson Sea Link can go as deep as 4,000 meters

21. R.O.V. r emotely o perated v ehicle small robot operated from boat cables to boat safer and cheaper

22. A.U.V. autonomous underwater vehicle small robot no cables to surface

23. Satellites used for navigation and to map ocean bottom

24. Satellites Global map of ocean floor gravity from Geosat and ERS-1 satellite altimetry

25. Side scan sonar uses sound waves and computer imaging to get an image of the ocean bottom towed behind ship can determine benthic habitats

26. Side scan sonar