Please solve question 1. kb surface P Surface P AHEHED ENET WTARCTC ThH 10, 188
ID: 285939 • Letter: P
Question
Please solve question 1.
kb surface P Surface P AHEHED ENET WTARCTC ThH 10, 188 Crushed Marce melting temperature depends on pressure and chemical composition. Temperatures in the Earth increase about 25°C for every kilometer of depth, and this increase in temperature with depth is one of the major agents of metamorphism. For a rock at depth, the weight of the overlying mass of rock causes confining pressure, which squeezes the rock in all directions. The general effect of confining pressure is to reduce the volume, causing the rock to have higher density ( Figure 5.la and b). Confining pressure directly relates to depth of metamorphism and is similar to the pressure scuba divers experience as they descend into deep water. A common unit for atmospheric pressure is the bar, which is approximately the same as an atmosphere. Standard pressure is one atmosphere (1 atm) or 1.01325 bars at Earth's surface at sea level; but varies slightly depending on the weather conditions. Greater pressures may be measured in kilobars (kb); 1 kb is 1,013.25 times atmospheric (atm) pressure. Pressure increases about 3 kb for every 10 km depth. The rocks we see at Earth's surface rarely reached depths greater than 40 km (12 kb). David J. and Jane M. Matty Pse fra (a) Increasing confining pressure 1. Use the caption of Figure 5.la. Calcu- late the pressure in kilobars and list it in the blanks above the right two cups. Indi- cate how many times this is than standard pressure at sea level. Increasing differential stress (c)Explanation / Answer
I am using approximation for this as no clear values of depth are mentioned:
I think the first glass is crushed in not more than 1 km depth
So, for 1 km = 0.3 kb =303.97 atm
Pressure = 1013.25 + 303.97 = 1317.225 atm =1.33 kb which is approximately 1.3 times the pressure at surface.
I think the second glass is crushed in around 3 km depth
So, for 3 km = 0.9 kb =911.925 atm
Pressure = 1013.25 + 911.925 = 1925.175 atm =1.95 kb which is approximately 2 times the pressure at surface.