Answer:
0.267mm/yr
7.25 mm
Explanation:
Given the following:
Estimated time since erosion began = 6 million years
Greatest depth of canyon = about 1.6km
The mean rate of erosion in millimeter per year:
Mean rate = Depth of canyon / time
Depth of canyon in millimeter:
1 km = 1000000 mm
1.6km = (1.6 × 1000000) = 1,600,000 mm
Mean rate = 1,600,000mm/ 6,000,000 years
Mean rate = 0.26666 mm/yr
Mean rate = 0.267 mm/year
B.) If rate of erosion = 0.267mm/yr
Date of birth = 30 / 10 / 1992
Today's date = 5 / 9 / 2020
Date difference = 27 years 55 days
Total number of days = (27 *365) + 55 = 9,910 days
Rate of erosion per day = 0.267 / 365 = 0.0007315 mm / day
Change in depth from date of birth till today:
0.0007315 mm/day × 9,910 days
= 7.2492328 mm
= 7.25 mm deeper
