Wallace Creek has been offset by 130.0 meters (430 feet) to the right along the fault. The age of stream deposits indicates that this offset began 3700 years ago. Based on these figures, calculate the average rate of movement along this segment of the fault in centimeters per year (or inches per year). Keep in mind that your answer is an estimate of the longterm average, not the expected movement each year.
The following questions are based on Map T-25a, Figure 37-3, a detailed topographic map of the San Andreas Fault, Figure 37-5, a stereogram of the San Andreas Fault in the Carrizo Plain National Monument, and Figure 37-6, a portion of the “McKittrick Summit, California,” quadrangle. “Wallace Creek” is an offset stream that has been labeled for you on Figure 37-6.
Most of the movement between the Pacific Plate side and the North American Plate side of the San Andreas Fault is released abruptly after years of accumulating strain—at which time the fault ruptures with a displacement of several meters.
Further, it appears that different segments of the fault remain locked for different periods of time. In a general way, the size of an earthquake expected to occur along a segment of the fault system relates to the length of time the fault accumulates strain before rupturing. The longer the strain accumulates, the larger the earthquake when the fault finally ruptures.
(a) Total offset in centimeters (or inches): _______________ centimeters (or inches)
(b) Average offset per year: __________ centimeters per year (or in./yr.)
(a) 13,000 cm (5160 in.)
(b) 3.5 cm (1.4 in.)
You might also like to view...
The most important factor influencing soil type and thickness is ____________________
Fill in the blank(s) with correct word
Of the following common alternatives to fossil fuel resources, which is not renewable?
A) hydroelectric B) nuclear C) solar D) wind
________ is the theory that describes the motion of the Earth's lithosphere
A) Plate tectonics B) Sea floor spreading C) Pangaea D) Metamorphism
Which of the following statements is false?
A. Earthquakes occur along faults B. The largest North American earthquake in recorded history occurred in Missouri C. Tsunamis are generally caused by volcanic eruptions D. Human activities can trigger earthquakes