Question

the hawaiian islands formed as the pacific plate moved over a hot spot.
island distance from hot spot (km) approximate age (millions of years)
hawaii 0 0
maui 180 1.3
oahu 320 3.5
kauai 520 5.1
questions:

1. what happens to the age of the islands as you move farther from hawaii (the hot spot)?
2. what pattern does this show about how islands are formed over a hot spot?
3. use the data to predict the age of an island 700 km away from hawaii.

part c: critical thinking

1. how are the patterns in the mid - atlantic ridge data and the hawaiian islands data similar?
2. what do both sets of data tell us about how earths tectonic plates move?

Explanation:

Question 6

As we move farther from Hawaii (the hot - spot), we observe from the data that the age of the islands increases. For example, Hawaii is 0 million years old at 0 km from the hot - spot, Maui is 1.3 million years old at 180 km, O'ahu is 3.5 million years old at 320 km and Kaua'i is 5.1 million years old at 520 km.

Question 7

This shows that islands are formed over a hot - spot in a sequential manner. The hot - spot is a stationary source of magma. As the tectonic plate moves over the hot - spot, new islands are formed at the location of the hot - spot, while the previously formed islands move away from the hot - spot and age over time.

Question 8

First, we find the rate of age increase per kilometer.

Step1: Calculate the rate of change

We take two data points, say (180, 1.3) and (320, 3.5). The rate of change (slope $m$) of age ($y$) with respect to distance ($x$) is given by the formula $m=\frac{y_2 - y_1}{x_2 - x_1}$.
$m=\frac{3.5 - 1.3}{320 - 180}=\frac{2.2}{140}\approx0.0157$ million years per km.

Step2: Predict the age

We use the point - slope form of a line $y - y_1=m(x - x_1)$. Using the point (0, 0) and $m = 0.0157$, for $x = 700$ km, we have $y=0.0157\times700 = 10.99\approx11$ million years.

Question 9

Both the Mid - Atlantic Ridge data and the Hawaiian Islands data show a relationship between distance and age. In both cases, as the distance from a central feature (hot - spot for Hawaiian Islands and ridge axis for Mid - Atlantic Ridge) increases, the age of the geological features (islands or oceanic crust) increases.

Question 10

Both sets of data tell us that Earth's tectonic plates are in motion. The increase in age with distance from a central feature (hot - spot or ridge axis) indicates that new material is being formed at the central location (magma upwelling at hot - spots or ridge axes) and the older material is being carried away as the plate moves.

Answer:

1. The age of the islands increases.
2. Islands are formed sequentially as the plate moves over the hot - spot, with new islands forming at the hot - spot and older islands moving away and aging.
3. Approximately 11 million years.
4. Both show a relationship where age increases with distance from a central feature.
5. Tectonic plates are in motion, with new material forming at a central location and older material being carried away as the plate moves.