1.
What part of kelp holds it to the ocean floor beneath it?
Correct Answer
B. Holdfast
Explanation
The holdfast is the part of kelp that attaches it to the ocean floor. It acts as an anchor, keeping the kelp securely in place despite the movement of the water. The holdfast is made up of a mass of root-like structures that grip onto rocks or other solid surfaces, providing stability and support for the kelp plant.
2.
Who collected the first major statistics for wind and ocean currents?
Correct Answer
B. Matthew Maury
Explanation
Matthew Maury is the correct answer because he is widely recognized as the person who collected the first major statistics for wind and ocean currents. Maury was a United States Navy officer and oceanographer who conducted extensive research on oceanography and meteorology. His work laid the foundation for modern oceanography and weather forecasting. Maury's collection of data on wind and ocean currents greatly contributed to our understanding of these phenomena and their impact on navigation and maritime activities.
3.
Dissolved salt makes up what percentage of ocean water?
Correct Answer
B. 3.50%
Explanation
Dissolved salt makes up approximately 3.50% of ocean water. This percentage represents the salinity of the water, which is the total amount of dissolved salts and other minerals present. The majority of the dissolved salts in ocean water are sodium and chloride ions, which give seawater its characteristic salty taste. This percentage may vary slightly depending on factors such as location and depth, but on average, it is around 3.50%.
4.
In which ocean would one find the Sargasso Sea?
Correct Answer
D. Atlantic
Explanation
The Sargasso Sea is located in the Atlantic Ocean. It is a region in the North Atlantic Ocean bounded by four currents forming an ocean gyre. The sea is unique because it is characterized by its distinctive brown Sargassum seaweed, which floats on the surface of the water. The Sargasso Sea is known for its rich biodiversity and is an important habitat for various marine species, including turtles, eels, and fish.
5.
Besides Greenland, what is the largest island in the Atlantic Ocean?
Correct Answer
C. Britain
Explanation
Britain is the correct answer because it is the largest island in the Atlantic Ocean after Greenland. Cuba is located in the Caribbean Sea and is not part of the Atlantic Ocean. Iceland is the third largest island in the Atlantic Ocean, and Ireland is the second largest.
6.
In what year did Alfred Wegner publish "The Origin of Continents and Oceans"?
Correct Answer
A. 1915
Explanation
Alfred Wegner published "The Origin of Continents and Oceans" in 1915. This book presented his theory of continental drift, which proposed that the continents were once joined together in a single landmass called Pangaea and have since drifted apart. Wegner's theory was groundbreaking and laid the foundation for the modern understanding of plate tectonics.
7.
What is the name of the ancient ocean that surrounded the Pangea land mass?
Correct Answer
B. Panthalassa
Explanation
Panthalassa is the correct answer because it was the name of the ancient ocean that surrounded the Pangea land mass. Panthalassa means "all sea" in Greek, indicating that it was a global ocean that existed during the Paleozoic and Mesozoic eras. It covered almost all of the Earth's surface and played a crucial role in the formation and breakup of supercontinents like Pangea.
8.
What percentage of Earth's volcanic activity occurs on the ocean floor?
Correct Answer
D. 80%
Explanation
80% of Earth's volcanic activity occurs on the ocean floor. This is because the majority of Earth's volcanoes are located along the boundaries of tectonic plates, where the Earth's crust is being pulled apart or pushed together. These boundaries are predominantly found in the ocean, such as the mid-ocean ridges and subduction zones. As a result, a significant amount of volcanic activity, including eruptions and the formation of new oceanic crust, takes place underwater. This makes the ocean floor the primary location for volcanic activity on Earth.
9.
What surface rock comprises the majority of the Earth's crust in the area beneath the oceans?
Correct Answer
D. Basalt
Explanation
Basalt is the correct answer because it is a type of volcanic rock that is commonly found in the Earth's oceanic crust. It is formed from the solidification of lava and is known for its dark color and fine-grained texture. Basalt makes up a large portion of the oceanic crust due to the abundance of volcanic activity and lava flows in these areas. It is different from the other options, such as limestone, granite, and obsidian, which are not as prevalent in the oceanic crust.
10.
Who is credited as being the discoverer of the Pacific Ocean?
Correct Answer
C. Balboa
Explanation
Balboa is credited as being the discoverer of the Pacific Ocean. He was a Spanish explorer who is known for being the first European to lead an expedition to have seen or reached the Pacific from the New World. In 1513, Balboa crossed the Isthmus of Panama and reached the Pacific Ocean, claiming it for Spain. This discovery opened up new trade routes and had a significant impact on the exploration and colonization of the Americas.
11.
What did the earthquake that triggered the 2004 Indian Ocean tsunami register on the Richter scale?
Correct Answer
A. 9
Explanation
The earthquake that triggered the 2004 Indian Ocean tsunami registered a magnitude of 9 on the Richter scale. The Richter scale is used to measure the magnitude of earthquakes, with each whole number increase representing a tenfold increase in the amplitude of the seismic waves. A magnitude of 9 indicates an extremely powerful earthquake, capable of causing widespread destruction and generating a significant tsunami. The 2004 Indian Ocean earthquake was one of the strongest ever recorded, resulting in massive devastation and loss of life across multiple countries in the region.
12.
How many countries were affected by the 2004 Indian Ocean tsunami?
Correct Answer
B. 11
Explanation
The 2004 Indian Ocean tsunami affected a total of 11 countries. This natural disaster was triggered by a massive undersea earthquake off the coast of Sumatra, Indonesia. The tsunami waves traveled across the Indian Ocean, causing widespread devastation in countries such as Indonesia, Thailand, Sri Lanka, India, and the Maldives. The impact of the tsunami was felt as far away as Somalia and South Africa. The death toll reached over 230,000 people, making it one of the deadliest natural disasters in history.
13.
What fraction of the Earth do oceans cover?
Correct Answer
A. Three-Fourths
Explanation
Oceans cover three-fourths of the Earth's surface. This means that out of the total area of the Earth, three-fourths of it is covered by oceans. The Earth is made up of approximately 70% water, with the majority of it being in the form of oceans. This is a significant amount and highlights the importance of oceans in our planet's composition and ecosystem.
14.
Which ocean is the smallest and shallowest?
Correct Answer
D. Arctic Ocean
Explanation
The Arctic Ocean is the smallest and shallowest of the world's five major oceans. Covering an area of about 14 million square kilometers, it is roughly 1.5 times the size of the United States. The average depth of the Arctic Ocean is about 1,038 meters (3,406 feet), which is much shallower compared to the other oceans. The Arctic Ocean is located around the North Pole and is surrounded by Eurasia and North America. It is known for its harsh, icy conditions and significant seasonal variation in ice cover. Due to its size and depth, the Arctic Ocean has unique ecosystems and plays a crucial role in the Earth's climate system, particularly in relation to sea ice and global temperature regulation.
15.
What valuable metal is found in the oceans but is expensive to extract?
Correct Answer
A. Gold
Explanation
Gold is a valuable metal that is found in the oceans but is expensive to extract. It is present in small quantities in seawater and can be extracted through various methods such as desalination, electrolysis, and ion exchange. However, the extraction process is costly and requires significant resources and energy. Therefore, despite the presence of gold in the oceans, its extraction remains expensive and not economically viable on a large scale.