Final answer:
Seismic energy is transmitted more efficiently in the eastern U.S. compared to California due to the older, more cohesive geological makeup of its crust, which has fewer faults and allows seismic waves to travel farther without losing much energy.
Step-by-step explanation:
When compared to California, seismic energy in the eastern U.S. is transmitted more efficiently. The geological makeup of the Earth's crust in the eastern United States allows seismic waves to travel farther without losing as much energy. This is due to the colder, older, and more solid rocks in the eastern part of the continent compared to the younger and more fractured crust found in California.
One of the reasons for this difference is that the crust in the eastern regions of the US is older, more continuous, and generally has fewer faults than in California. Fewer faults mean that there are fewer disruptions and barriers for the seismic waves to navigate, allowing them to retain more of their energy over long distances. In contrast, the tectonic environment in California is highly active, with numerous faults and fragmented geological structures which attenuate the seismic energy more quickly.