that is a portion that is a south westerly portion of san francisco that has some special earthquake hazards. we are here to talk about the geology of this area. why don't you tell us about what is going on? >> there is a giant step here at the edge of the escarpment, the edge of the landslide. all the land to the west of us is part of a landslide that is upwards of 200 feet deep. it goes underneath the ocean. it causes damage and it was mapped by the earliest geologists'. there are many kinds of rocks here. there is a big sequence of merced formation. this is a base in deposit that was formed by the interaction at the end of the continental

margin. >> this is just on top. this is the same material that we were looking at at the last site. you can see it is on our way to the last side. it is deposited here by wind. it is 40-50 feet thick. this acts as a big sponge. the water flows through and it gets in a lower formation and then the water level starts to rise and it becomes a reservoir for water. this is dissipated during the more dry months of the year.

>> this forms a big long skinny basin and runs into san francisco. it is the coastal bluffs areas that are subject to erosion from the waves and the ground water that comes out and you start to lose this. this is the largest example of failure for a long part of the coast. it has been moving continuously for a long time. >> the ocean was at the same level as we are standing. in 1982, and massive slide occurred further to the north of and one day it moves 5 feet and by the second day it moves 30 feet out. all of that land down below was sitting out here. it was a great deal logic

feature of the landslide further to the south. there were houses on top and there was a very steep slope. you can see some debris slides where the sand is slowing. then you drop into a gully or a drainage swell. the top of the landslides' is just a drop in the middle where another clock has pulled away from the edge. the higher hill on the outside edge of the rich and the depression is the drop. surface erosion is an acute issue. >> you can see the evidence of the houses directly adjacent. we have similar conditions to that. if you go around the corner around the seacliff, where in fact there has been significant movement and in fact many of the

homeowners along that portion of the seacliff have had to come back in and do extensive foundation repair and massive walls to protect the home while the slope [inaudible] >> here we have the shallow slides, a debris slides. during earthquakes, they are both activated and the movement on the deep sea slides accelerates as well as the official material that erodes. >> if there's one point that is brought home from this discussion of landslides is san francisco is a part of the community that experiences many

types of landslides, rockfalls, deportations. we need to be aware of the geologic and topographic setting we are in. when we are planning to build our home or buy a home or at additions to the home. if i have one suggestion, that is to seek information from the apartment building inspection. if you're not satisfied, there is ample information there. a geologist needs an opinion of the stability of the environment you're in. >> the building department will typically require that kind of information. people will do a major edition. what we are wondering is why we require that information. >> great, thank you very much. it is terrific. it is fun to see a lot of the

city. thank you. >> the court is now accepting applications for the civil grand jury. this investigative watchdog body is comprised of 19 public spirited citizens. >> we are seeking candidates from all walks of life, 18 or older, who will bring to the grand jury a wide spectrum of talent, ideas, and issues of concern. >> for more information, visit the civil grand jury website at sfgov.org/courts or call