Passage VII
Tiny marine organisms build shells from calcite (CaCO3) dissolved in seawater. After the organisms’ death, the shells sink. Some shells dissolve before they reach the seafloor, but some form layers of calcareous ooze (CaCO3-rich sediment). Figure 1 shows how seawater’s degree of saturation with respect to CaCO3 and the rate at which CaCO3 dissolves change with depth. The CaCO3 compensation depth (CCD) represents the depth beneath which CaCO3 dissolves faster than it precipitates. Figure 2 shows typical depths at which various seafloor sediments are found. Figure 3 shows the percent coverage for 2 seafloor sediments in 3 oceans.
40. Figure 1 shows that the rate at which CaCO3 dissolves increases the most between which of the following depths ?
Your Answer is
Correct Answer is J
Explanation
Looking at the right half of figure 1, it can be seen that when the depth is 5 km-5.5 km, the slope of the curve is relatively increased, indicating that the rate at which CaCO3 dissolves has increased p>