Ocean zones

Question 1

What are the two types of ocean zones?

Answer 1

Pelagic zones and Benthic zones

Pelagic zones refer to water column zones, while Benthic zones refer to seafloor zones.

Question 2

What is the Intertidal Zone?

Answer 2

The area found between high and low tide marks

It can be dry or underwater depending on the tide.

Question 3

What is the depth range of the Epipelagic Zone?

Answer 3

0–200 m

This zone is also known as the Sunlight Zone.

Question 4

What allows photosynthesis in the Epipelagic Zone?

Answer 4

Sunlight

Phytoplankton perform most of the photosynthesis in this zone.

Question 5

What percentage of marine life is found in the Epipelagic Zone?

Answer 5

~90%

This zone is crucial for marine biodiversity.

Question 6

What are the temperature extremes in the Epipelagic Zone?

Answer 6

−2°C (polar oceans) to 32°C (Red Sea)

Temperature varies significantly based on geographic location.

Question 7

How does pressure change in the Epipelagic Zone?

Answer 7

Increases 1 atm per 10 m depth

This pressure change is crucial for understanding marine life adaptations.

Question 8

What characterizes the Mesopelagic Zone?

Answer 8

Dim light; no photosynthesis

This zone is also known as the Twilight Zone.

Question 9

What is the pressure range in the Mesopelagic Zone?

Answer 9

20–100 atm

This pressure affects the types of organisms that can live here.

Question 10

What phenomenon occurs at around 500–800 m in the Mesopelagic Zone?

Answer 10

Thermocline: rapid temperature drop

This is important for understanding the thermal structure of the ocean.

Question 11

What is the depth range of the Bathypelagic Zone?

Answer 11

1,000–4,000 m

This zone is also referred to as the Midnight Zone.

Question 12

What is the temperature in the Bathypelagic Zone?

Answer 12

~4°C

This zone is characterized by total darkness.

Question 13

What is the Abyssopelagic Zone also known as?

Answer 13

Abyssal Zone

It covers 83% of the ocean and 60% of Earth’s surface.

Question 14

What is the typical temperature range in the Abyssopelagic Zone?

Answer 14

3–4°C

This zone is known for very low oxygen levels.

Question 15

What geological features are found in the Abyssopelagic Zone?

Answer 15

• Mid-ocean ridges
• Volcanoes
• Islands
• Hydrothermal vents

These features contribute to the unique ecosystem of the zone.

Question 16

What are black smokers and white smokers?

Answer 16

• Black smokers: hot, sulfur-rich
• White smokers: cooler, mineral-rich

Both are types of hydrothermal vents found in the Abyssopelagic Zone.

Question 17

What do gas hydrates trap in the Abyssopelagic Zone?

Answer 17

Gases like methane

Methane is 20 times more potent than CO₂ as a greenhouse gas.

Question 18

What is the Hadalpelagic Zone also known as?

Answer 18

Hadal Zone

This zone includes both pelagic and benthic areas.

Question 19

What is the maximum depth of the Challenger Deep in the Mariana Trench?

Answer 19

10,924 m

It is the deepest known point in the ocean.

Question 20

What is the pressure in the Hadalpelagic Zone?

Answer 20

~1,100 atm

This pressure is equivalent to the weight of about 50 jumbo jets.

Question 21

True or False: The Hadalpelagic Zone is continuous.

Answer 21

False

It consists of 13 troughs and 33 trenches.

Question 22

Why are there very few human visits to the Hadalpelagic Zone?

Answer 22

Due to extreme pressure

This presents significant challenges for exploration.