Question

A010) One of the most active (and best studied) earthquake-prone areas is the San Andreas transform fault that forms a plate boundary between the North American Plate and the Pacific Plate. Turn on the San Andreas Major Ruptures folder to see rupture extents for three major earthquakes that have affected the San Andreas– Fort Tejon (1857, Mag. 7.9), San Francisco (1906, Mag. 7.8), and Loma Prieta (1989, Mag. 6.9). Also, in the Layers panel, turn on Gallery > Earthquakes.
   
Plate Boundary Earthquakes - San Andreas Fault, Wallace Creek, CA. What is the sense of offset along the San Andreas Fault? (i.e., Walk along either segment of Wallace Creek toward the fault. At the fault, determine the direction you turn to find the offset segment of the stream across the fault.)

	right lateral (rocks on the west side of the San Andreas Fault move to the NW)
	left lateral (rocks on the west side of the San Andreas Fault move to the SE)

A011) Plate Boundary Earthquakes - San Andreas Fault, Wallace Creek, CA. Use the Ruler tool to determine the distance (m) that Wallace Creek has been offset by recent motion along the San Andreas Fault (measure between the Problem 11 placemarks).

	~75 m
	~100 m
	~303 m
	~160 m

A012) Plate Boundary Earthquakes - San Andreas Fault, Wallace Creek, CA. Assuming that slip accumulates along the fault at about 6 cm/yr, how many years might it have taken to accumulate the slip that was released to produce the observed offset of the stream?

	~2667 yrs
	~5033 yrs
	~1010 yrs
	~10,100 yrs

A015) Plate Boundary Earthquakes - San Andreas Fault, CA. Keep the San Andreas Major Ruptures folder turned on to show the extents of segments of the San Andreas Fault that have slipped during major seismic events. Using seismic gap analysis (where segments of a fault that have not recently slipped form "gaps" of accumulating strain transferred from adjacent slipped fault segments that highlight areas of greater potential for a "seismic" event), which placemark highlights a segment of the San Andreas Fault that has a high risk for an earthquake?

Question 13 options:

	Problem 15a
	Problem 15b
	Problem 15c
	Problem 15d

Answer 1

Q10 : The earth is crust facture in to the a series of "plate" that have been moving slow over the earth surface for million of years . Two of these moving plate meet in the Western California ; the boundary between them is the San andreas fault . The Pacific plate (on the west ) (on the east ) causing earthquake along the fault . San andreas is the master of fault . generally is applied to the northeastern most branch it

Q11:plate boundary earthquake San Andreas fault determine the distance(m) the Wallace Creek has been ofset motion along the San Andrea fault ~130 m but correct but answer is there ~100m highly not expet gradient slip .

Q12: the slip accumulated along the fault about the 6cm/yr ,~2667yr many might the slip accumulated ofset of the stem.

Q15: the greater san francisco bay area has high like wood fracture damaging earthquake as it straddle the San anAndre fault system of North America and Pacific tectonic plate .