Los Angeles Real Estate Geology

Los Angeles Real Estate Geology


– James Campbell with
Coldwell Banker Realty and I’m here with my rock
expert, Steve Miller, to talk today about geology. – Hi, I’m Steve Miller
with Miller Geosciences. We do engineering geology
in Southern California. We deal mostly with hillside projects where people are building in hillsides. We don’t want them to build on landslides or we don’t want them to
build on earthquake faults. – I’ve been out in the field. I have risked life and limb
collecting these specimens that are different variations of rocks that can be found in the
Santa Monica mountains to bring you information on what we’ve got going on underneath our feet. A house is only as good as its foundation and they should really be saying that the foundation’s only
as good as the bedrock that it’s built on. What got you interested
in rocks and geology? – My mom was a school
teacher and she had stuff like this around all the time. You know, dinosaurs and
fossils and my dad loved maps. And the other half of
geology was all about maps. Well I started taking geology,
everything kind of fit. – A lot of what you’re,
geology is looking at is the soil as well but
mainly kind of what’s going on with the bedrock ’cause that’s
what you really build on if I’m not mistaken, right? – In the hillside primarily
we like to see things on bedrock, yeah because
that generally tends to be the most stable thing to build on. Most secure thing to build on. Nobody wants a house moving, so. We try to anticipate those problems. – When I’m dealing with home buyers on their purchases of
property, I usually recommend a real estate geological
inspection for hillside homes. All hillside homes. Would you also recommend
geological inspections for beach properties and
properties on flat land as well? – Yeah they are typical or sometimes when you need to have
geological inspections. We don’t like to call them inspections. We like to call them evaluations. – Geological evaluations. – And the reason for is inspections infer that we know everything
there is to know about the project and we really don’t. We’re evaluating what we can
see based on our experience. These are good examples
of the types of rock that we build it in
Santa Monica mountains. There’s, you know, we got
pretty good coverage here. To the average person it
probably all looks like rock. (laughter) – It just looks like a
bunch of rocks, right? – These are shales that
you see on the north, primarily on the north side
of the Santa Monica mountains. Well there are very specific
names for rock types. Now we get a group of rocks, we call it a quote unquote formation. We’re able to map these units
throughout the hillsides you know, based on their
characteristics, okay. So everywhere I see a
gray slate, I’m gonna draw a line on a map and I’m gonna say okay this whole area here
is underlined by slate. Okay, and this little area over here is all underlined by shale. At some point, they break apart. And these sometimes get
water and greased up in between them and
they can actually slide. So you can have sliding in the bedrock. If it’s flat like this,
it’s not gonna go anywhere. If it’s sitting on an
edge, it’s gonna slide. – Yes. – The slate is builds kind of the core of the Santa Monica mountains. The Santa Monica mountains are actually are kind of a fold it’s
come up, it’s been pushed up as the tectonic plates
come together they kind of crunch things up and
they fold and they fall. Whatever else. The strongest rocks, granite’s good. But salt is good too
but salts really hard. The only problem with the salt is that it’s really hard to dig in. Weathering can affect
the strength of a slope. Stability and whether
you wanna build on it. And if you build on it,
how do you build on it? Strength characteristics
here are non-homogenous in other words, they’re not the same. So, if I’m trying to break
it this way, it’s hard. If I’m trying to break
it this way, it’s easy. – Interesting. – So, that orientation matters a lot. That’s the bedding plane characteristic that we talk about in our reports. If you have an adverse
bedding plane condition then you have to be
able to provide some way of supporting that bedding plane. – Can you like, somehow
like, put an anchor in there or something so that it’s less likely to, you know, if you put a couple pins in there or something. – Yeah they’re called shear pins. – Shear pins. Okay, so that is a thing. – It’s an actual thing or friction. Some people just, they
design put friction piles in. So you would say you have a situation where the bottom half of this is supported and the top half isn’t. So it could still move here. What you wanna do is
you wanna put your pin down through the top and into the bottom and anchor it on the part
that’s not gonna move. – When you’re doing a geological fix, how long will you get out of that? ‘Cause obviously things erode. Over time, you know, everything
will be changed completely. – Usually the life expectancy of a house, single family residence is about 40 years is what we anticipate it to be. – Okay. – Obviously they last longer. We go back and we find houses
that are 150 years old. Not many people live in one
place more than 40 years. – That’s definitely true
in Southern California. – Quick sell it and give it
to some other guy. (laughter) – Sell it before. (laughter)
– We’ll check that one out. (laughter) This is, this flaking or
desiccation of a rock. It’s just like flaky skin. (laughter) – Rocks have feelings too. Sandstone specifically, they’re
very much layered, right? Sedimentary rock, right? – Sedimentary rock. – It was formed by erosion
action that left like particles of sediment that over time kind of became crushed. – You can see now, this
might be, you know, one storm and another
storm and another storm. This is a long ways off the coast but each one of these little bands is from a push of sediment that
gets washed in the ocean. – Yeah the sand, right? – And it goes out and then
it settles down in the soil in the water column and it creates a band. Well then along comes
a lot of overburdening. You get piles of this stuff miles high and it kind of compresses
it and in between you get little seashells so
the calcium from the seashells gets changed around and turn into cement so now we get a cement rock. As you start to push
things down in the ground you create pressure, the
pressure creates heat and it starts changing things and that’s when we start to get what they call metamorphic rocks instead of sedimentary rocks. These old remnant layers
that got mushed together. – Wow, yeah you can see
the, at one time this rock was these and then they just got squished so high under pressure
that it turned into that. – That’s right. So the structure of it was originally in some of these materials has changed. Usually, the metamorphic
rocks are a little older than sedimentary rocks as a rule of thumb. The sequence is a giant cycle. You get rocks that go from sandstones to stale stones off shore. They get shoved down to the ground. They turn into slates. They melt they into granite. As a melt comes up to
the ground it cools off it turns into granite. The granites get eroded. They get washed back out
into the ocean it silts. The silts get subducted
back into the ground again they turn into slates, the slates melt and they turn into granite. You know, around, around, around. – The new kids on the block
are these igneous rocks, right those that shoot out of the
core of the Earth in volcanoes. – In volcanoes yeah and lava
flows and that kind of stuff. – Well thank you so much Steve for getting together with me today. If anybody is in need of
a geo technical expertise, how do they get ahold of you? – You can contact me at
[email protected] or you can call me at 661-299-2206. (upbeat rock music) – New take, new take. – Take two. – Take two. (laughter) Action.

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