Deep-Ocean Exploration Technology

Question 1

Scientists report that only about 30 % of the world’s ocean floor has been surveyed in fine detail with acoustic mapping. Which statement best explains why this percentage is so low?

Accepted Answer

High‑resolution sonar requires a research vessel to tow equipment very close to the seabed, and the great cost and limited ship time mean only a fraction of the ocean can be covered in detail.

Answer

Sound waves cannot travel far underwater, so they are useless for mapping large areas of the seafloor.

Answer

The extreme pressure at depth breaks sonar devices, so acoustic mapping can be done only in shallow water.

Answer

Mapping relies on visible landmarks on the ocean floor, and the deep ocean lacks such landmarks.

Question 2

A team wants to investigate a hydrothermal‑vent community at a depth of about 4 km. Which statement best explains how a crew‑ed submersible and a tethered ROV can be used together to study the site?

Accepted Answer

The submersible carries the scientists down and lets them work directly at the vents, while the ROV is lowered from the submersible to capture high‑resolution video, map the seafloor with sonar, and collect extra samples without putting the crew at additional risk.

Answer

The ROV is launched from the research ship and dives to the vents on its own, sending live video to the crew inside the submersible that remains on the surface.

Answer

The crewed submersible stays at the surface and controls the ROV, which alone can retrieve large rock samples and bring them up to the ship.

Answer

Both the submersible and the ROV are equipped with identical manipulator arms, so the scientists can choose whichever vehicle they prefer for every task, making the other vehicle unnecessary.

Question 3

Which of the following best compares the main challenges of sending a vehicle to the deepest ocean trenches with those of landing a rover on the Moon?

Accepted Answer

The deep ocean exerts crushing pressure (over 1,000 atmospheres), is near freezing, and blocks radio signals, making vehicle design and communication much harder than the Moon’s vacuum and low gravity.

Answer

The deep ocean is colder than the Moon, so keeping instruments warm is the biggest challenge, while the Moon’s lack of atmosphere makes landing vehicles impossible.

Answer

Because the Moon has no water, scientists can’t use sonar there, so mapping the Moon is harder than exploring the ocean floor.

Answer

The main difficulty in deep‑ocean exploration is that there is no sunlight, whereas the Moon gets plenty of sunlight, making power generation the only issue on the Moon.

Try three questions

Scientists report that only about 30 % of the world’s ocean floor has been surveyed in fine detail with acoustic mapping. Which statement best explains why this percentage is so low?

A team wants to investigate a hydrothermal‑vent community at a depth of about 4 km. Which statement best explains how a crew‑ed submersible and a tethered ROV can be used together to study the site?

Which of the following best compares the main challenges of sending a vehicle to the deepest ocean trenches with those of landing a rover on the Moon?

Keep going on this shelf