Plate Tectonics Trivia MCQ Quiz!

Seafloor spreading occurs at divergent boundaries. These boundaries are where tectonic plates move away from each other, creating a gap. Magma rises from the mantle to fill this gap, forming new oceanic crust. As more magma erupts and cools, it creates a continuous process of seafloor spreading. This process is responsible for the formation of mid-ocean ridges and the expansion of the ocean floor.

Scientists believe that convection currents are the force behind the plate tectonics theory. Convection currents occur in the Earth's mantle, where hot material rises and cooler material sinks. This movement of material creates a circular motion, which in turn causes the plates on the Earth's surface to move. As the hot material rises, it pushes the plates apart, and as the cooler material sinks, it pulls the plates back together. This continuous cycle of convection currents is responsible for the movement and interaction of the Earth's tectonic plates.

Earthquakes can occur due to faults. Faults are fractures in the Earth's crust where rocks on either side have moved relative to each other. When stress builds up along a fault line and exceeds the strength of the rocks, it can result in an earthquake. The sudden release of energy causes seismic waves to radiate from the fault, leading to ground shaking. Therefore, the statement "Earthquake can happen because of fault" is true.

Transform boundaries are associated with shearing stresses and shallow earthquakes. At transform boundaries, two tectonic plates slide horizontally past each other. This movement creates friction and stress along the boundary, leading to the accumulation of strain. When the stress exceeds the strength of the rocks, it is released in the form of earthquakes. These earthquakes tend to be shallow because the sliding occurs near the Earth's surface. In contrast, subduction zones, spreading centers, and continent-continent convergence are associated with other types of plate movements and have different earthquake characteristics.

Horizontally directed, tensional stresses result in the stretching and pulling apart of rock layers. This creates a space for the rocks to move downward along inclined fault planes, forming normal faults. In normal faults, the hanging wall moves down relative to the footwall. Therefore, normal faults are the products of horizontally directed, tensional stresses.

When two units collide, the one who is closer to the contact will experience more compressive stress. This means that the force applied during the collision will cause the unit closer to the contact point to be compressed more than the other unit. Compression refers to the reduction in volume or the squeezing together of particles in a material due to an applied force. In this case, the collision between the units causes the particles in the unit closer to the contact point to be compressed, resulting in increased compressive stress.

Mesosaurus is the correct answer because its fossil was found in both South America and South Africa, which supported the continental drift hypothesis. The presence of the same species in two separate continents indicates that these land masses were once connected and later drifted apart. Mesosaurus was a small aquatic reptile, and its ability to swim across large bodies of water would have been highly unlikely. Therefore, the only plausible explanation for its presence in two distant locations is that the continents were once joined together and later separated.

The given evidence suggests that there is a connection between the presence of glaciers in the polar region and the climate. The evidence implies that glaciers were initially found in the tropical region but have now moved to the polar region due to changes in the climate. This supports the idea that glacial evidence and the study of glaciers can provide valuable insights into understanding climate patterns and changes over time.

Oceanic-continental convergence refers to the collision between oceanic and continental crusts. In this process, the denser oceanic crust sinks beneath the less dense continental crust due to its subduction into the mantle. This subduction causes the oceanic crust to start sinking while the continental crust remains buoyant. This collision leads to the formation of various geological features such as volcanic arcs, mountain ranges, and deep-sea trenches.