Question

1. review the diagram on page 11. why is anomaly v not included in your calculations?

anomaly v was not included because it represents mid-ocean ridge
______________________________________________________________________
______________________________________________________________________

1. according to your data, which anomaly has the fastest estimated rate of sea-floor spreading?

______________________________________________________________________
______________________________________________________________________

1. between which two plates is the rate of seafloor spreading greater?

the rate of seafloor spreading is greater between the pacific and nazca plates.
______________________________________________________________________
______________________________________________________________________

1. why did many scientists reject wegener’s hypothesis of continental drift?

many scientists rejected wegener’s hypothesis of continental drift because he could not propose a
credible mechanism to explain how the continents moved.
______________________________________________________________________
______________________________________________________________________

1. explain how seafloor spreading provides an explanation for how continents move across the surface of

the planet.
______________________________________________________________________
______________________________________________________________________

1. think back to your answer to the question from page 5 “what do you think earth’s continents will look

like 225 million years in the future?” revise your answer using evidence from the lesson.
they will likely have moved further apart,collided to form new landmasses or even assemble into a
new super-continent, completely altering the current world map.

Explanation:

Question 2

To determine which anomaly has the fastest sea - floor spreading rate, we need to calculate the rate for each anomaly. The formula for the rate of sea - floor spreading is \( \text{Rate}=\frac{\text{Distance}}{\text{Time}} \). We would first obtain the distance (in centimeters or other appropriate units) of each anomaly from the mid - ocean ridge and the time (in years) corresponding to that anomaly (usually related to the age of the oceanic crust at that anomaly). Then we calculate the rate for each anomaly. The anomaly with the highest value of \( \frac{\text{Distance}}{\text{Time}} \) will have the fastest spreading rate. Since the specific data is not provided here, but generally, if we assume we have data like for anomaly X, distance \( d_X \) and time \( t_X \); for anomaly Y, distance \( d_Y \) and time \( t_Y \), we calculate \( r_X=\frac{d_X}{t_X} \), \( r_Y = \frac{d_Y}{t_Y} \) etc., and compare the rates.

Seafloor spreading occurs at mid - ocean ridges. Magma rises from the mantle, cools, and solidifies to form new oceanic crust. This new crust pushes the older crust away from the ridge. The continents are attached to the oceanic plates (lithospheric plates). As the oceanic plates move due to seafloor spreading (the new crust being added at the ridge and pushing the plates), the continents that are part of these plates are carried along. So, the movement of the oceanic plates (driven by seafloor spreading) causes the continents to move across the Earth's surface.

Based on the concept of plate tectonics (supported by seafloor spreading evidence), the Earth's plates (including continental plates) are in constant motion. The rate of plate movement can be estimated from seafloor spreading rates. Over 225 million years, the continents will continue to move according to the direction and rate of their respective plate movements. If the current trend of plate movement (e.g., the Pacific - Nazca plate boundary has a relatively fast spreading rate, and other plate boundaries have their own rates) continues, continents may collide (like the formation of supercontinents in the past), move further apart, or re - assemble into a new supercontinent. For example, if the African plate is moving towards the Eurasian plate, over time they may collide, and other plates will also move in their respective directions, leading to a re - arrangement of the continental landmasses.

Answer:

(The answer would depend on the specific data. For example, if after calculating the rates for each anomaly, anomaly A has a rate of \( 10\space cm/year \), anomaly B has \( 8\space cm/year \), then the answer would be the anomaly with the highest rate, say "Anomaly A has the fastest estimated rate of sea - floor spreading" (replace A with the actual anomaly from the data).)

Question 5