Ocean Boulevard Landslides. Landslide definitions.

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Ocean Boulevard Landslides

Transcript of Ocean Boulevard Landslides. Landslide definitions.

Page 1: Ocean Boulevard Landslides. Landslide definitions.

Ocean Boulevard Landslides

Page 2: Ocean Boulevard Landslides. Landslide definitions.

Landslide definitions

Page 3: Ocean Boulevard Landslides. Landslide definitions.

GrabensA graben is a down-dropped block between

two scarps. They often form within the bodies of rotational landslides.

Page 4: Ocean Boulevard Landslides. Landslide definitions.

Head ScarpThe head scarp is at the top of a landslide.

Structures and utilities that cross these structures may be deformed or broken by landslide movement.

Page 5: Ocean Boulevard Landslides. Landslide definitions.

Landslide Toe

The toe is the bottom of the landslide. It is

often marked by a bulge or mound.

Along Ocean Blvd, the landslide toe is

constantly eroded by the ocean.

Page 6: Ocean Boulevard Landslides. Landslide definitions.

UtilitiesUtilities along Ocean Blvd include electrical, telephone,

water, and sewer. The arrows show utility poles that are moving because they are in the body of a landslide.

Page 7: Ocean Boulevard Landslides. Landslide definitions.

Underground Utilities

Movement on the head scarp has

caused damage to local water and

sewer lines, particularly east of

the Distillery.

Page 8: Ocean Boulevard Landslides. Landslide definitions.

Evidence of Recent Movement

scarp lines shown with tick-marks on down-dropped side

Page 9: Ocean Boulevard Landslides. Landslide definitions.

landslide locations are approximate, shown as head scarp only

Page 10: Ocean Boulevard Landslides. Landslide definitions.

Future MovementThe landslides now affecting Ocean Boulevard will continue to move.

The toes of these failures are continually being eaten away by the ocean,

which means the slope cannot reach equilibrium.

Page 11: Ocean Boulevard Landslides. Landslide definitions.

Future GrowthThe landslides along Ocean

Boulevard will probably continue to grow and change.

The head scarps will migrate inland, and the bodies of the slides may expand laterally.

The ocean bluff will continue to retreat, sometimes in the

form of large slumps.

Seismic ground shaking and/or the introduction of

significant amounts of water into these landslides may accelerate these changes.

cracks opening inDistillery’s upper parkinglot

old foundation erodingfrom below