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This is geology B with all of us
trampled. 

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Many hundreds of films have been
shot on location in the American

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West. 
The rugged inhospitable 

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Landscapes are an integral part 
of what gives so many American 

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westerns their distinctive 
character. 

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Although the region is vast 
stretching from the Rockies in 

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Wyoming and Colorado to Utah. 
New Mexico, Nevada, Arizona, and

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California, a few locations have
captured, the Lion's Share of 

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the film industry's attention 
What is it about these 

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Landscapes that makes them so 
photogenic and how do they get 

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that way? 
In this episode, Craig Jones 

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cast light on the answers to 
these questions. 

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He is a professor in the 
department of geological 

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Sciences at Colorado University 
at Boulder, his research aims to

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uncover the origin of mountains 
and elevated topography and 

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continents primarily in the 
Western United States. 

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His main tool for doing this is 
seismology, but he also 

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incorporates observations from 
other disciplines such as 

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gravity measurements palette. 
Ultimate tree and petrology. 

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He's written a book on the 
Sierra, Nevada and leads field 

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trips to the rugged terrains. 
We're discussing here. 

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Craig Jones, welcome to geology 
B. 

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Thank you very much for having 
me before we start talking about

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the specific locations that 
became Hollywood favorites. 

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How should we approach the 
question of understanding how 

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the Salient features of today's 
landscape came? 

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To be the simplest way to think 
of it is in three parts. 

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One is basically the intrinsic 
characteristics of the Rocks 

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themselves. 
So how they're actually 

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constructed what materials were 
used. 

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Then the physical and chemical 
processes that then affect the 

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Rocks after their created 
typically we're talking about 

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erosional characteristics and 
then to view these kind of 

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Landscapes, the present-day 
climate is an important 

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component to be able to 
understand why we get these kind

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of Landscapes. 
Okay, we're going to focus on 

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just two very distinct areas. 
In the American West that have 

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been the favorite of film 
directors, the Colorado Plateau,

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which covers parts of Colorado, 
Utah. 

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New Mexico, and Arizona, and the
Alabama Hills which live, 50 

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kilometers, west of Death Valley
in the Sierra, Nevada. 

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Let's start with the Colorado 
Plateau, concentrating on 

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Monument Valley, where over 60 
major films were shot, starting 

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with Stagecoach in 1939 and 
including the classic, John Ford

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movies with John. 
Wayne will also touch on a few 

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other locations in the Colorado 
Plateau. 

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Such as the Grand. 
Canyon Zion and Bryce Canyon. 

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What is the origin of the rocks 
in the Colorado Plateau? 

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The rocks that are present in. 
All of these places are 

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sedimentary rocks. 
Rocks are made up of what was 

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originally mud and sand. 
Or little limey creatures. 

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It's varied a little bit over 
the history of the Colorado 

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Plateau. 
Most of these deposits have been

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made within about the last 500 
million years. 

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One of the important 
characteristics of these 

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sedimentary rocks is the 
variation of them over time and 

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it's that combination of the 
variation of seas rising and 

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falling. 
Lying and mountains, rising and 

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falling that gives you the 
opportunity to have this diverse

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arrangement of sedimentary rock,
which is what leads to these 

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dramatic Landscapes. 
So, you mentioned shorelines. 

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So, do we know what the 
depositional context was for the

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materials that make up these 
rocks? 

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Yes, it's varied quite a bit. 
So for instance, if you're at 

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the Grand Canyon and you stand 
on the rim of the Grand Canyon, 

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you're standing on the Kaibab 
Limestone, which is a marine 

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deposit but you go to Monument 
Valley. 

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Valley and you look at, 
wonderful spires that are there 

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and you're looking at the dish, 
a Sandstone, which is sand dunes

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kind of like what you would have
now in the Sahara. 

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And then there are fluvial 
deposits River deposits that 

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are, for instance, sitting in 
the organ rock formation sitting

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at the base of those spires in 
Monument Valley. 

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So we've had quite a variation 
in a really is the fact that 

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it's come and gone with these 
different environments that 

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allows for all this diversity. 
Hmm. 

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Interesting. 
We have both Marine Fluval and 

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alien deposition in different 
places. 

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What sort of time scale? 
Are we talking about when this 

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deposition got going? 
And how long did it last? 

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Well, of course, it varies from 
place to place for instance, at 

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the Grand Canyon, most of what 
you're looking at the bottom is 

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the to Pete Sandstone, which is 
a little over 500 million years 

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old. 
And at the top that Kaibab 

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limestone is a little over 300 
million years old. 

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So there you're talking about 
200 million years of time. 

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Of course, there's a significant
amount of that time. 

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No rocks were deposited at all 
you move over to Monument Valley

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and you're looking at somewhat 
younger rocks which overlap in 

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part. 
The Kaibab Limestone but they 

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were closer to an ancestral 
rocky mountain range that 

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existed here in Colorado, 
Monument Valley to the West in 

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Utah and Arizona. 
So that time period was actually

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so much shorter for everything. 
You see in Monument Valley, 

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probably maybe 50 million years.
And then if you went to 

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something much younger, your 
talks about Bryce Canyon 

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National Park, the Rocks, there 
are pretty much deposited within

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about 10 million years It's so 
different places are sampling, 

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different parts of the geologic 
history of the Colorado Plateau 

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and are representing different 
durations of time. 

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What was the larger tectonic 
context at the time was this 

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before or after the creation of 
Pangaea and did North America 

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already exist as a intact piece 
of continent at that time? 

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Well, North America was 
definitely at that point. 

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Before Pangaea assembled we call
it laurentia because parts of 

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what her today, North America 
were at the time on other 

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continents. 
But this area in the 

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southwestern part of the United 
States was definitely part of 

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laurentia and part of North 
America. 

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Parts of that geology predate 
Pangaea. 

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So for instance, the section you
see in the Grand Canyon for the 

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most part is older, the stuff. 
You see in Monument Valley was 

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accumulating pretty much. 
At the time that Pangaea was 

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finally being assembled. 
And so those answers to Rocky 

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Mountains, were a product in 
part of the final closure of an 

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ocean between South America and 
North America. 

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And then number of the rocks 
that are present are younger and

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actually date to win. 
North America had separated once

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again from pieces of Pangaea. 
So Zion National Park. 

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The big Sandstone Cliffs there, 
Bryce Canyon National Park, both

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of those house. 
State Pangaea. 

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So, as you mentioned earlier, 
the depositional environments 

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are very different from place to
place. 

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Some of them were Fluval 
submarine, some alien. 

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But even in a given spot, you 
can see from the way that 

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formations change as you go up 
and down across an exposure. 

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For example, there is a huge 
variation, what accounts for 

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that in a given place and how 
does that wind up affecting the 

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rocks and how they appear and 
how strong they are? 

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One of the big factors in the 
Colorado Plateau again, is the 

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ancestor Rockies. 
So prior to that time, period 

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things were relatively quiet and
the plateau was fairly close to 

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sea level. 
So further west when you were 

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little bit deeper water and so 
you have things like the mauve 

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Limestone which is prominent 
Cliff former in the Grand Canyon

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and you go a little further east
and you find some fairly thin 

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Shoreline deposits and some 
Coastal deposits. 

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AS Global sea level changes, of 
course, you can get these little

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variations but then you throw in
something, like the ancestor 

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Rockies. 
And they start to erode that 

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material has to go somewhere. 
And one of the places we went, 

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was the Colorado Plateau. 
And so, the vast pile of red 

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rock that, you find in Monument 
Valley that you also find in the

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Grand, Canyon, the soup. 
I group those sedimentary rocks.

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Are basically because you now 
have this big source of sand and

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gravel and mud. 
Mud that was flooding across the

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landscape as those mountains 
finally. 

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Were worn down, roughly, 250, 
million years ago, then you 

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started to see The Return of the
oceans coming back into parts of

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the plateau. 
Similarly much later on the 

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modern Rocky. 
Mountains were created. 

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Starting roughly 75 million 
years ago, and as part of that, 

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the river systems were disrupted
and we ended up with some very 

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large lakes. 
One of those large lakes is 

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actually the Words of the 
sedimentary rock that we have in

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Bryce Canyon. 
So it's been a mix of 

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broad-scale global changes some 
local changes because of 

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tectonic activity. 
Okay. 

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So let's talk about the second 
phase then about what's happened

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since these sediments were 
originally laid down in order to

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get a rose in the very first 
thing you need is elevation. 

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If the rock is sitting down near
or below sea level, not much is 

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going to happen. 
Once you've managed to graze The

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Rock on up, then erosion is 
going to be able to act on it. 

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There's two different aspects of
that the main one really for our

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purposes is physical erosion. 
So it's basically the weathering

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breaking down the Rock and then 
transporting it away as a Roshan

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and different kinds of rock will
behave differently. 

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So, the floovio sandstones and 
mudstones typically, they're 

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very thin bedded when you look 
at them at kind of will look 

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like grub Ali. 
Slopes Then these chance, he's 

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those sandstones tend to be 
quite massive. 

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You see what's called 
cross-bedding in it, which comes

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from actually Frozen sand dunes.
Basically that have been 

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preserved, and that material 
tends to form large Cliffs, the 

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limestone's, and some other 
things like conglomerates, which

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are much coarser than the sand 
Stones. 

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Those tend to be far more 
resistant, they'll be ledge 

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Farmers, but they're typically 
not very thick. 

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So, irosian the physical erosion
of this material results in 

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different looking things. 
The other thing that's 

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important, I think for a lot of 
people is really the diversity 

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of colors. 
So for instance, we have what's 

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called, The Painted Desert, 
which is just to the east of the

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Grand Canyon, this is actually 
the Chinle formation and it's 

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largely. 
So colorful, in the case of the 

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Chin Li is because of volcanic 
ash deposits, which have lent 

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colors from, not only from, I 
Iron which is the most common 

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Rock coloring agent about from 
manganese and copper and 

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occasionally some other metals 
which will give you the pinks 

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and Maroons and some greens and 
even some bluish looking Rock, 

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most of the Red Rock though that
you see it's iron and that iron 

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has been oxidized. 
It's been rusted, the iron might

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have originally been in the rock
as little grains of magnetite. 

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It could have been deposited as 
hematite. 

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There are some other mineral 
grains that are iron rich The 

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key thing though is that you 
need these deposits to have been

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made in an environment where you
have oxidation, which is 

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typically going to be at or 
above sea level. 

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So, in particular, the really 
Red Rocks, say at the base of 

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the Pinnacles in Monument 
Valley. 

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Those tend to be fluvial 
sediments, they were deposited 

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by Rivers. 
So The Rock was basically being 

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exposed the muds before it 
became Rock, was being exposed 

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to the atmosphere. 
These things. 

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Weathered into these very very 
red colors which are now 

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exposed. 
And so most of the red rock that

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we have in the Colorado Plateau 
has been produced in that 

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manner. 
But there are places where the 

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rock is kind of whitish. 
Is that a different environment?

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Yeah, in particular, the case of
the Navajo is kind of 

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interesting. 
So again, the Navajo is what 

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forms the tremendous cliffs in 
Zion National Park and you'll 

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see both red and white colors in
the Navajo, pretty much. 

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With the white above the red and
for a long time geologists 

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argued about just exactly 
whether the Navajo started white

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and was stained red. 
Whether it started red and was 

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bleached white. 
I think starting red and 

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bleached white has got the best 
support. 

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And the interesting thing is 
that what would do this is if 

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you had a reducing environment 
one which is the opposite of 

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oxidizing, and it turns out that
if you have Petro chemicals 

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petroleum and gas and other sort
of organic, And that move up in 

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the Rock, the Navajo Sandstone 
is actually a very porous 

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Sandstone. 
It's what we would consider an 

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aquifer. 
So, as petroleum is released 

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from some underlying say, 
limestone's it rises up and it 

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maybe gets trapped in the Navajo
Sandstone above. 

229
00:13:28,700 --> 00:13:32,000
It is something called the 
temple cap Limestone which then 

230
00:13:32,000 --> 00:13:35,500
prevents any further upward 
motion of these fluids, the 

231
00:13:35,500 --> 00:13:39,200
fluids being reducing change the
color of the Rock from red to 

232
00:13:39,200 --> 00:13:42,400
White. 
So it's been Suggested, I think 

233
00:13:42,400 --> 00:13:46,100
with good evidence that a lot of
the white Navajo Sandstone that 

234
00:13:46,100 --> 00:13:50,600
we find in the southwestern, us 
used to be a big oil Reserve. 

235
00:13:50,900 --> 00:13:54,300
That subsequently was breached 
by erosion, all their oil and 

236
00:13:54,300 --> 00:13:58,000
gas went to the atmosphere, went
into the surface waters and 

237
00:13:58,000 --> 00:14:00,200
we've, now been left with these 
different colors. 

238
00:14:00,800 --> 00:14:04,400
Was there any particular 
Confluence of circumstances that

239
00:14:04,400 --> 00:14:08,900
led to the formation of the 
incredibly dramatic rock, towers

240
00:14:08,900 --> 00:14:13,600
in Monument Valley The big thing
that is true in Monument Valley 

241
00:14:13,600 --> 00:14:17,400
is first, you have at the 
bottom, the very bottom you have

242
00:14:17,400 --> 00:14:21,200
a fairly resistant Rock unit 
that provides a base and sitting

243
00:14:21,200 --> 00:14:26,300
on top of that are some fluvial 
deposits which is basically the 

244
00:14:26,300 --> 00:14:31,200
organ rock formation and then 
you have this and see the desha 

245
00:14:31,200 --> 00:14:34,200
sandstone and the trick of 
course, with this sort of Cliff 

246
00:14:34,200 --> 00:14:36,500
former, is that the way? 
I sometimes? 

247
00:14:36,500 --> 00:14:38,600
Think about it. 
If you went to the beach and you

248
00:14:38,600 --> 00:14:42,100
had sand and you had for some 
reason, a pile Dominoes and you 

249
00:14:42,100 --> 00:14:45,500
set them up on end, kind of 
like, if you're trying to knock 

250
00:14:45,500 --> 00:14:47,700
over a whole series of dominoes,
but you actually bring them 

251
00:14:47,700 --> 00:14:50,000
close together. 
So that they're actually right 

252
00:14:50,000 --> 00:14:53,200
up against one another, they'll 
sit there just fine. 

253
00:14:53,600 --> 00:14:56,700
So long as the sand is sitting 
underneath it, but if you start 

254
00:14:56,900 --> 00:15:00,300
digging away at the sand at the 
edges of Domino's, basically 

255
00:15:00,300 --> 00:15:03,400
start to fall in as the base of 
they sit on basically starts to 

256
00:15:03,400 --> 00:15:07,100
become unstable and that's kind 
of what happens with these big 

257
00:15:07,100 --> 00:15:10,300
Cliff warmers is that as long as
you have something firm 

258
00:15:10,300 --> 00:15:13,900
underneath Neith, they'll 
support these tremendous Cliffs,

259
00:15:14,300 --> 00:15:16,400
but the moment you start to eat 
away at that material 

260
00:15:16,400 --> 00:15:21,200
underneath, then they fail 
sometimes quite dramatically and

261
00:15:21,200 --> 00:15:23,900
still preserve a cliff. 
So, as the cliff Retreats it 

262
00:15:23,900 --> 00:15:29,200
stays this big vertical, cliff 
and that variation in the style 

263
00:15:29,200 --> 00:15:31,700
of the rock. 
That was deposited going from 

264
00:15:31,700 --> 00:15:36,100
the much more muddy fluvial. 
Rocks of the Oregon rock that 

265
00:15:36,100 --> 00:15:41,700
sits below the deshays and stone
transitioning to the Big thick, 

266
00:15:42,000 --> 00:15:46,800
just pure sand aeolian, sand, 
stones of the desha gives you. 

267
00:15:46,800 --> 00:15:49,400
That wonderful contrast that 
gives you this. 

268
00:15:49,400 --> 00:15:51,900
Incredibly dramatic and iconic 
typography. 

269
00:15:52,100 --> 00:15:54,400
I'm about six out because all 
around it. 

270
00:15:54,800 --> 00:15:57,300
The Sandy based became unstable 
on the Rocks. 

271
00:15:57,300 --> 00:16:00,100
Just fell away and have been 
washed away by Rivers. 

272
00:16:00,100 --> 00:16:03,100
Is that right? 
Yes, that would be accurate. 

273
00:16:03,300 --> 00:16:08,200
And what about the massive 
cliffs in Zion, or the Pinnacles

274
00:16:08,200 --> 00:16:11,600
and Bryce. 
So the Zions very much, the same

275
00:16:11,600 --> 00:16:15,400
as Monument Valley that's 
younger again in terms of the 

276
00:16:15,400 --> 00:16:19,200
Navajo Sandstone is younger than
the stuff in Monument Valley. 

277
00:16:19,200 --> 00:16:23,900
And in fact it was probably one 
of the largest sand Seas on 

278
00:16:23,900 --> 00:16:26,200
Earth. 
Zion is about the thickest of 

279
00:16:26,200 --> 00:16:29,200
the Navajo. 
Sandstone, the case there is 

280
00:16:29,200 --> 00:16:32,000
that you have the K into 
formation underneath which has 

281
00:16:32,000 --> 00:16:35,600
almost exactly like the organ 
Rock in terms of it being a 

282
00:16:35,600 --> 00:16:37,700
fluvial deposit that can be 
eroded away. 

283
00:16:38,200 --> 00:16:41,800
The neat thing about Zion is 
that as you walk Upstream, if 

284
00:16:41,800 --> 00:16:45,800
you go Upstream in the main 
Canyon eventually, the walls 

285
00:16:45,800 --> 00:16:49,300
come together and you can walk 
up the Narrows of the Virgin 

286
00:16:49,300 --> 00:16:51,200
River. 
The Virgin River is the river 

287
00:16:51,200 --> 00:16:54,500
draining Zion and you can reach 
places where you can reach 

288
00:16:54,500 --> 00:16:58,600
across and you could touch both 
sides of the Canyon from one 

289
00:16:58,600 --> 00:17:01,000
spot. 
And when you're doing that 

290
00:17:01,000 --> 00:17:03,600
you're now standing on the 
Navajo Sandstone you're no 

291
00:17:03,600 --> 00:17:07,300
longer standing on any of the 
underlying sedimentary rocks. 

292
00:17:07,599 --> 00:17:12,000
And so that's a place where the 
Strength of these sandstones to 

293
00:17:12,000 --> 00:17:15,599
resistance. 
Basically, to collapsing really 

294
00:17:15,599 --> 00:17:18,900
stands out, you know, there are 
places in the Narrows, you look 

295
00:17:18,900 --> 00:17:23,099
up and you cannot see the sky 
because it's basically this slot

296
00:17:23,300 --> 00:17:26,099
and these kind of slot, canyons 
are relatively common. 

297
00:17:26,099 --> 00:17:31,700
In the Colorado, Plateau Bryce 
is a much younger story and it's

298
00:17:31,700 --> 00:17:34,600
different because in Bryce you 
have what are called hoodoos. 

299
00:17:35,300 --> 00:17:37,600
So, the thing that stands out 
about Bryce aside from the 

300
00:17:37,600 --> 00:17:41,000
colors, which are these bright 
oranges, Are these Pinnacles. 

301
00:17:41,200 --> 00:17:44,400
And in this case, you're dealing
with a differential resistance 

302
00:17:44,400 --> 00:17:47,100
to weathering, that's present in
some of the layers. 

303
00:17:47,100 --> 00:17:51,500
So some of the layers are Lake 
deposits there really to a 

304
00:17:51,500 --> 00:17:54,400
geologist or sort of ugly, 
they're actually kind of hard to

305
00:17:54,408 --> 00:17:57,700
interpret because they were 
altered a fair bit after they 

306
00:17:57,700 --> 00:18:01,800
were deposited, but part of that
was that some areas are cemented

307
00:18:01,800 --> 00:18:06,200
in some areas aren't and there's
a bunch of cracks. 

308
00:18:06,200 --> 00:18:09,500
We call them joint to indicate, 
there's no real motion across 

309
00:18:09,600 --> 00:18:13,100
Cross them, and these cracks act
as places where weathering 

310
00:18:13,100 --> 00:18:17,100
proceeds very rapidly. 
And then in between the cracks, 

311
00:18:17,100 --> 00:18:19,600
weathering is much slower. 
And as a result, if you have 

312
00:18:19,600 --> 00:18:23,800
cross-cutting sets of these 
joints, you end up then with 

313
00:18:24,200 --> 00:18:29,400
isolated Pinnacles and depending
on how efficacious the erosion 

314
00:18:29,400 --> 00:18:31,100
is. 
And the case for Bryce, it's 

315
00:18:31,100 --> 00:18:34,600
basically a steep-sided 
Amphitheater, where erosion 

316
00:18:34,600 --> 00:18:37,800
works very, very well. 
You flush away all the material 

317
00:18:37,800 --> 00:18:40,700
that's between these Pinnacles 
in your Then with these dramatic

318
00:18:40,700 --> 00:18:44,400
Hooters. 
Okay, so turning now to the 

319
00:18:44,400 --> 00:18:48,900
third and final phase that you 
mentioned, the reason the rocks 

320
00:18:48,900 --> 00:18:53,300
are in plain sight from Horizon 
to Horizon is because this area 

321
00:18:53,300 --> 00:18:58,600
is, so extremely arid and 
nothing can grow, why is it so 

322
00:18:58,600 --> 00:19:02,000
dry? 
There's two pieces to that one, 

323
00:19:02,000 --> 00:19:06,400
is that we're kind of on the 
edge of the global desert built 

324
00:19:06,500 --> 00:19:08,900
that you find near the Tropic of
Cancer. 

325
00:19:09,600 --> 00:19:15,100
So you're not quite up into the 
big wet part of the higher 

326
00:19:15,100 --> 00:19:18,800
latitudes, but a huge part of it
is that the Colorado Plateau is 

327
00:19:18,800 --> 00:19:21,900
surrounded by mountains that are
significantly higher than it. 

328
00:19:22,900 --> 00:19:26,800
So, storms at this latitude tend
to come from west to east 

329
00:19:26,800 --> 00:19:30,100
through the winter and what 
those storms encounter to the 

330
00:19:30,100 --> 00:19:33,300
West is the Sierra Nevada. 
And this year, Nevada does a 

331
00:19:33,300 --> 00:19:37,100
perfectly fine job of earning 
its name by scraping off a lot 

332
00:19:37,100 --> 00:19:40,600
of the moisture. 
So very little is actually left 

333
00:19:40,600 --> 00:19:43,200
and even what little is left 
then encounters what are called 

334
00:19:43,200 --> 00:19:45,900
the high plateaus at the very 
west side of the Colorado 

335
00:19:45,900 --> 00:19:49,300
Plateau and the high plateaus 
scrape off a little bit more. 

336
00:19:49,300 --> 00:19:52,300
So when you get in the interior 
of the plateau, there's very 

337
00:19:52,300 --> 00:19:54,900
little moisture making its way 
there. 

338
00:19:55,700 --> 00:19:58,400
Now, there are times of the year
where you do get storms, moving 

339
00:19:58,400 --> 00:20:01,900
from east to west. 
Those of us who live here on the

340
00:20:01,900 --> 00:20:03,400
east side of the Rockies 
actually. 

341
00:20:03,400 --> 00:20:07,700
See this typically in early 
spring where moisture coming, 

342
00:20:07,700 --> 00:20:10,100
maybe from the Gulf of Mexico. 
Chicago's trying to work its way

343
00:20:10,100 --> 00:20:12,100
west. 
And again, in encounters 

344
00:20:12,100 --> 00:20:13,600
mountains, it encounters the 
Rocky. 

345
00:20:13,600 --> 00:20:16,500
Mountains, Rocky Mountains, 
again, scrape off all the 

346
00:20:16,500 --> 00:20:20,100
moisture as they are good falls 
down the other side, it dries 

347
00:20:20,100 --> 00:20:23,500
out and again the Colorado 
Plateau kind of gets conked out 

348
00:20:23,500 --> 00:20:27,000
of any significant moisture. 
The last Direction where you 

349
00:20:27,000 --> 00:20:30,700
might get moisture is from the 
South during the Summer monsoon 

350
00:20:30,700 --> 00:20:32,700
season. 
There, you run into What's 

351
00:20:32,700 --> 00:20:35,800
called the Mogollon Rim, which 
is not as high as this year in 

352
00:20:35,800 --> 00:20:38,400
Nevada, or the Rocky Mountains, 
but it's still higher than the 

353
00:20:38,400 --> 00:20:40,300
bulk. 
Of the Colorado Plateau. 

354
00:20:40,700 --> 00:20:43,600
And so, once again, you tend to 
scrape off the moisture that 

355
00:20:43,600 --> 00:20:46,600
might be coming in from the 
Summer monsoon. 

356
00:20:47,300 --> 00:20:51,400
So a little bit, is the global 
environment that the Colorado 

357
00:20:51,400 --> 00:20:54,400
Plateau finds itself in. 
But an awful lot of it is that 

358
00:20:54,400 --> 00:20:58,800
despite the fact that it's well 
over a mile and elevation in 

359
00:20:58,800 --> 00:21:02,400
large parts of the plateau, it's
surrounded by higher Rock, 

360
00:21:02,500 --> 00:21:05,400
higher mountains that basically 
prevent any of that moisture 

361
00:21:05,400 --> 00:21:09,800
from sneaking in. 
Okay, let's turn to our second 

362
00:21:09,800 --> 00:21:15,100
area of moviemaking Fame. 
The misleadingly named Alabama, 

363
00:21:15,100 --> 00:21:20,200
Hills in the Southern California
Sierra, Nevada mountains, its 

364
00:21:20,200 --> 00:21:23,700
proximity to Hollywood made it 
extremely popular with film 

365
00:21:23,700 --> 00:21:27,200
directors and over 300 films 
were shot there. 

366
00:21:27,700 --> 00:21:31,100
Such as High Sierra, with 
Humphrey, Bogart, Django, 

367
00:21:31,100 --> 00:21:35,700
Unchained, and many episodes of 
The Lone Ranger series, not to 

368
00:21:35,700 --> 00:21:39,800
mention tongue. 
Of truck and suv ads that were 

369
00:21:39,800 --> 00:21:43,800
shown on us television. 
This must be a completely 

370
00:21:43,800 --> 00:21:48,900
different geological story. 
Yeah and indeed it is almost all

371
00:21:48,900 --> 00:21:52,500
the rocks that you find in the 
Alabama Hills and this year 

372
00:21:52,500 --> 00:21:56,800
Nevada that sits behind it are 
granite's or Granite towards 

373
00:21:57,300 --> 00:22:00,300
where do these granite's come 
from typically. 

374
00:22:00,300 --> 00:22:03,800
What you're looking at is 
subduction of an oceanic plate 

375
00:22:03,900 --> 00:22:07,800
underneath the edge of the 
continent, as that water 

376
00:22:07,800 --> 00:22:11,700
saturated oceanic plate. 
The water is bound in minerals, 

377
00:22:11,700 --> 00:22:15,000
they become Unbound as you get 
to certain pressures and 

378
00:22:15,000 --> 00:22:18,000
temperatures. 
Water that then Rises off the 

379
00:22:18,000 --> 00:22:20,800
subducting slab. 
Interacts with the overriding 

380
00:22:20,800 --> 00:22:24,800
mantle melts, the mantle much as
throwing salt onto ice will 

381
00:22:24,800 --> 00:22:28,700
cause the ice to melt throwing 
water into the mantle causes the

382
00:22:28,700 --> 00:22:32,500
mantle to melt yielding Magnus 
that rise up into the crust. 

383
00:22:33,000 --> 00:22:37,700
And you end up creating 
volcanoes such as Mount Saint 

384
00:22:37,700 --> 00:22:41,300
Helens, Mount Rainier in the 
Pacific Northwest today and 

385
00:22:41,300 --> 00:22:43,500
underneath them. 
You produce these granite's. 

386
00:22:44,400 --> 00:22:48,700
So we're basically looking Being
at one of the longest-lived 

387
00:22:48,700 --> 00:22:52,200
volcanic arcs in the world at 
least over the past 500 million 

388
00:22:52,200 --> 00:22:55,700
years is the volcanic Arc that's
existed in this year. 

389
00:22:55,700 --> 00:23:00,200
In Nevada, from something like 
320 million years ago to about 

390
00:23:00,300 --> 00:23:02,600
80 million years ago. 
Okay? 

391
00:23:02,600 --> 00:23:08,200
So what's happened to this 
Granite since it was in placed, 

392
00:23:09,200 --> 00:23:11,300
so there's grants crystallize a 
depth. 

393
00:23:11,500 --> 00:23:13,800
The way that you get the nice 
big crystals, that you can see 

394
00:23:13,800 --> 00:23:17,500
in a granite, is by having a lot
of Time for the minerals to get 

395
00:23:17,500 --> 00:23:20,200
organized. 
And so you need to be at some 

396
00:23:20,200 --> 00:23:23,500
significant depth, some of the 
shallowest of the granite's may 

397
00:23:23,500 --> 00:23:25,400
have been at just five 
kilometers below. 

398
00:23:25,400 --> 00:23:29,400
The surface somewhere is deep is
almost 30 kilometers below the 

399
00:23:29,400 --> 00:23:31,600
surface. 
Well they're not at Great depth 

400
00:23:31,600 --> 00:23:34,800
anymore so you had to actually 
remove a lot of the material on 

401
00:23:34,800 --> 00:23:37,900
top for the most part that was 
done by erosion. 

402
00:23:38,500 --> 00:23:41,000
Well rose on top, were the 
volcanoes. 

403
00:23:41,500 --> 00:23:45,100
So the lavas and tephra is, and 
other volcanic materials. 

404
00:23:45,500 --> 00:23:47,600
Those were far More easily 
eroded. 

405
00:23:47,600 --> 00:23:52,100
And most of that material was 
removed by about 60 65 million 

406
00:23:52,100 --> 00:23:55,100
years ago. 
Subsequent to that you start 

407
00:23:55,100 --> 00:23:58,800
seeing in the sedimentary. 
Rocks the transition from the 

408
00:23:58,800 --> 00:24:02,200
volcanic materials being eroded 
to the granite's, being eroded 

409
00:24:02,200 --> 00:24:04,700
off. 
Again, in order to have erosion,

410
00:24:04,700 --> 00:24:07,200
you have to have elevation 
certainly in the late. 

411
00:24:07,200 --> 00:24:11,000
Cretaceous say 70 to 75 million 
years ago, the Sierra Nevada had

412
00:24:11,000 --> 00:24:15,400
to be high the big questions 
been since then exactly what's 

413
00:24:15,400 --> 00:24:18,700
happened. 
This actually leads us into a 

414
00:24:18,700 --> 00:24:23,700
little bit of controversy, 
there's two camps, basically one

415
00:24:23,700 --> 00:24:27,200
that thinks the Sierra, Nevada 
has stayed High much like it is 

416
00:24:27,200 --> 00:24:30,400
today pretty much since 70 
million years ago. 

417
00:24:30,600 --> 00:24:34,500
And the other Camp feels that 
the range was lower. 

418
00:24:35,000 --> 00:24:39,100
It eroded down and eroded down 
and ended up to be significantly

419
00:24:39,100 --> 00:24:42,000
lower than it is today. 
And is subsequently risen up in 

420
00:24:42,000 --> 00:24:45,400
about the last 10 million years.
If the evidence can be 

421
00:24:45,400 --> 00:24:48,700
interpreted to mean It was a 
fairly sudden uplift over a 

422
00:24:48,700 --> 00:24:51,800
certain period of time. 
This reminds me a little bit of 

423
00:24:51,800 --> 00:24:57,700
what Peter Molnar was talking 
about in his podcast to explain 

424
00:24:57,700 --> 00:25:04,000
the rapid uplift of Tibet. 
And I'm wondering if the seismic

425
00:25:04,000 --> 00:25:09,200
imaging under the Sierras is 
good enough to see if there's a 

426
00:25:09,200 --> 00:25:12,600
piece of mantle that might have 
dropped off, that could be 

427
00:25:13,000 --> 00:25:15,100
implicated here. 
Yeah. 

428
00:25:15,100 --> 00:25:18,400
So, I mean those of us who are 
inclined to think that the range

429
00:25:18,400 --> 00:25:22,300
is Young point to an anomaly, 
that long ago, I called it the 

430
00:25:22,300 --> 00:25:24,800
Isabella anomaly, and that name 
is stuck. 

431
00:25:25,200 --> 00:25:29,400
So this is a high-velocity I've 
lost in the sense of the speed 

432
00:25:29,400 --> 00:25:33,100
of seismic waves through the 
material body that sits in the 

433
00:25:33,100 --> 00:25:37,000
upper mantle going down to 
depths of around 300 kilometers,

434
00:25:37,000 --> 00:25:40,400
underneath the South Eastern, 
Great Valley, the South Western 

435
00:25:40,400 --> 00:25:45,000
Sierra Nevada, and it turns out 
volumetrically that this Very 

436
00:25:45,000 --> 00:25:48,300
much like the material that 
would have sat underneath the 

437
00:25:48,300 --> 00:25:51,100
high part of the Sierra Nevada, 
10 million years ago. 

438
00:25:51,800 --> 00:25:56,100
And unlike the situation in 
Tibet, our ability to image, 

439
00:25:56,100 --> 00:26:00,400
this is much better in the case 
of California in part, because 

440
00:26:00,400 --> 00:26:03,400
it's a smaller area. 
Logistically, it's much easier 

441
00:26:03,400 --> 00:26:06,900
to access. 
And, actually, the geometry of 

442
00:26:06,900 --> 00:26:10,000
earthquake sources for being 
able to do, tomography is very 

443
00:26:10,000 --> 00:26:13,000
good in California. 
So we have this, really 

444
00:26:13,000 --> 00:26:17,100
excellent image of this body. 
D, we also have evidence from 

445
00:26:17,200 --> 00:26:20,300
volcanic pipes that came up 
between 8 and 12 million years 

446
00:26:20,300 --> 00:26:23,700
ago, in this year in Nevada, 
that actually brought up pieces 

447
00:26:24,400 --> 00:26:27,700
of the uppermost. 
Mantle, in the lowest crust that

448
00:26:27,700 --> 00:26:31,200
used to be present in this year 
in Nevada and that material. 

449
00:26:31,500 --> 00:26:35,500
Some of it is basically just 
garnet and pyrrhic scene. 

450
00:26:35,500 --> 00:26:39,200
So it's a garnet peroxy night. 
This material is very, very 

451
00:26:39,200 --> 00:26:41,000
dense. 
It's denser than the mantle 

452
00:26:41,000 --> 00:26:44,400
underneath it it's gone today 
when we do it. 

453
00:26:44,600 --> 00:26:46,700
Jing under the high part of the 
range. 

454
00:26:46,700 --> 00:26:49,800
There is none of this material 
present under the range today, 

455
00:26:49,800 --> 00:26:52,800
but the material in the Isabella
anomaly. 

456
00:26:52,800 --> 00:26:56,400
The characteristics of it are 
perfectly compatible with that 

457
00:26:56,400 --> 00:27:00,000
Isabel anomaly containing a lot 
of this Garnet proximate. 

458
00:27:00,500 --> 00:27:04,300
So, it does seem like a weight 
in order to get the mountain 

459
00:27:04,300 --> 00:27:07,300
range to rise up as that you 
have removed. 

460
00:27:07,300 --> 00:27:10,600
This very dense material that 
sat at the bottom of the crust 

461
00:27:11,200 --> 00:27:14,200
and now you've just kind of 
poured it down this hole. 

462
00:27:14,900 --> 00:27:17,000
So it's on its way down into the
mantle. 

463
00:27:17,700 --> 00:27:21,500
Let's talk a bit about the 
shapes of the landscape in 

464
00:27:21,500 --> 00:27:25,400
contrast to Monument Valley in 
the Colorado Plateau, we don't 

465
00:27:25,400 --> 00:27:31,100
see tabletop mountains, stepped 
Cliffs and the towers that we 

466
00:27:31,100 --> 00:27:33,900
see there. 
It looks really different. 

467
00:27:34,900 --> 00:27:38,200
The first thing is, of course, 
the granite is far more uniform 

468
00:27:38,200 --> 00:27:40,700
in its Behavior. 
You're not going to have, but 

469
00:27:40,700 --> 00:27:44,600
rubble, a slope, and then a big 
cliff and some capping thing 

470
00:27:44,600 --> 00:27:47,900
that is more resistant, it's all
Granite. 

471
00:27:48,100 --> 00:27:51,400
But what really affects the way,
the granite Rhodes has a lot to 

472
00:27:51,400 --> 00:27:53,900
do with the climate. 
So, if we go back to the Alabama

473
00:27:53,900 --> 00:27:56,700
Hills, when you look at the 
Alabama Hills, it's these 

474
00:27:56,700 --> 00:28:00,900
rounded, knobs Chamber of 
Commerce, and Lone Pine likes to

475
00:28:00,900 --> 00:28:04,500
tell them is the oldest Hills in
the world, which is, This 

476
00:28:04,500 --> 00:28:08,300
they're not particularly old but
they give you that kind of sense

477
00:28:08,300 --> 00:28:10,800
that they've been there forever 
and they've been sort of rounded

478
00:28:10,800 --> 00:28:15,800
and ground down whereas the 
exact same rock that sits up on 

479
00:28:15,800 --> 00:28:18,600
the crest of the Sierra Nevada. 
That's in the background of 

480
00:28:18,600 --> 00:28:21,300
those movies. 
It's forming, these tremendous 

481
00:28:21,300 --> 00:28:25,300
spires and a rat's, horns, all 
kinds of wonderful. 

482
00:28:25,300 --> 00:28:30,200
Very sharp Alpine kind of 
geometry that still the granite 

483
00:28:30,200 --> 00:28:35,300
but there is being affected by 
Ice rything A sure plucking 

484
00:28:35,500 --> 00:28:37,900
glacial erosion glacial 
polishing. 

485
00:28:38,700 --> 00:28:43,400
So the glacial aspects acting on
the granite, give you these very

486
00:28:43,400 --> 00:28:48,600
different shapes than what 
you're going to see down low in 

487
00:28:48,600 --> 00:28:53,200
sort of the desert where the 
Alabama Hills are by and large 

488
00:28:53,200 --> 00:28:56,300
that uniformity of the rocket 
tends to give you these nice, 

489
00:28:56,300 --> 00:28:59,500
beautiful u-shaped valleys which
are classic shape that you'll 

490
00:28:59,500 --> 00:29:02,000
see in the Alps. 
You see them in much of this 

491
00:29:02,000 --> 00:29:04,900
year in Nevada, but the funny 
part about Here in Nevada. 

492
00:29:04,900 --> 00:29:09,300
Some places the granite is a 
little bit different so in the 

493
00:29:09,300 --> 00:29:13,200
Tuolumne drainage which is just 
North of Yosemite Valley, The 

494
00:29:13,200 --> 00:29:15,400
Rock, it's extraordinarily 
uniform. 

495
00:29:15,400 --> 00:29:17,900
And it has very, very few 
joints. 

496
00:29:17,900 --> 00:29:22,100
It has very few of these little 
cracks and so the glaciers were 

497
00:29:22,100 --> 00:29:24,400
not able to pluck any of the 
rocks out. 

498
00:29:24,600 --> 00:29:27,600
So when you look at the, What's 
called the Grand Canyon of the 

499
00:29:27,600 --> 00:29:30,800
to Olney, it's v-shaped, even 
though it had the thickest 

500
00:29:30,800 --> 00:29:34,300
Glacier in this year in Nevada, 
there was nothing for the The 

501
00:29:34,300 --> 00:29:38,700
glacier to do, but just polish 
it in contrast Yosemite Valley. 

502
00:29:39,100 --> 00:29:42,100
It has this amazing diversity 
of, lots of different kinds of 

503
00:29:42,100 --> 00:29:44,600
granite. 
And as a result, it has lots and

504
00:29:44,600 --> 00:29:47,700
lots of different fractures and 
things in different places. 

505
00:29:47,700 --> 00:29:50,100
So that parts of it are 
extremely fractured parts of it 

506
00:29:50,100 --> 00:29:54,700
are not like El Capitan and that
combination has allowed glaciers

507
00:29:54,700 --> 00:29:59,500
to excavate to an extreme degree
so much so that there are 2,000 

508
00:29:59,500 --> 00:30:03,000
feet of sediment that actually 
sits in the bottom of Yosemite 

509
00:30:03,000 --> 00:30:05,100
Valley. 
So the original Are you shaped 

510
00:30:05,100 --> 00:30:08,400
Valley has been filled in with 
sediment and so you have these 

511
00:30:08,400 --> 00:30:11,700
nice flat Meadows practically 
going up to the base of these 

512
00:30:11,700 --> 00:30:15,000
tremendous Cliffs and what about
the Final Phase? 

513
00:30:15,000 --> 00:30:21,600
That present-day climate all the
Rocks there in the Alabama Hills

514
00:30:21,700 --> 00:30:25,500
exposed as in the Colorado 
Plateau, because it's a desert 

515
00:30:25,500 --> 00:30:27,400
where nothing can grown cover 
them up. 

516
00:30:28,300 --> 00:30:31,300
Yeah, certainly and the Alabama 
Hills, you are in one of the 

517
00:30:31,300 --> 00:30:35,900
biggest rain Shadows on Earth. 
The high peaks of the Sierra, 

518
00:30:35,900 --> 00:30:40,400
Nevada to the west or for over 
4000 meters, the passes are 

519
00:30:40,400 --> 00:30:44,800
nearly 4,000 meters. 
So all that precipitation that 

520
00:30:44,800 --> 00:30:47,000
would be coming from the West 
get scraped off. 

521
00:30:47,000 --> 00:30:49,100
To the Alabama, Hills are very 
much desert. 

522
00:30:49,100 --> 00:30:53,200
It's extremely dry. 
Is it Mary Austin's book, land 

523
00:30:53,200 --> 00:30:57,900
of little rain was about Owens 
Valley and just the fact that 

524
00:30:57,900 --> 00:31:01,100
she chose to title the book that
tells you just how that 

525
00:31:01,100 --> 00:31:04,800
situation is. 
In contrast the Closure in the 

526
00:31:04,800 --> 00:31:08,600
high part of the range is 
because of actually having all 

527
00:31:08,600 --> 00:31:13,200
of that moisture and having been
in an ice age, a lot of soil got

528
00:31:13,200 --> 00:31:16,200
scraped off. 
And you just have lots and lots 

529
00:31:16,200 --> 00:31:20,500
of bare rock, and there's only 
so much vegetation that can claw

530
00:31:20,500 --> 00:31:24,200
its way into these bear. 
Granite Cliffs, what do you 

531
00:31:24,200 --> 00:31:28,500
consider to be some of the most 
important jalaja call problems 

532
00:31:28,500 --> 00:31:31,200
that have yet to be solved in 
the American West? 

533
00:31:32,000 --> 00:31:36,400
You know, I think it comes down 
to paleo elevation for 

534
00:31:36,400 --> 00:31:40,700
geophysicists elevation is what 
would call the zeroth order. 

535
00:31:40,700 --> 00:31:44,500
Observable. 
It is the most important basic 

536
00:31:44,500 --> 00:31:46,800
piece of information. 
And we kind of take it for 

537
00:31:46,800 --> 00:31:51,400
granted today, that you look 
around and you say, well, it's 

538
00:31:52,900 --> 00:31:55,300
yes, we can measure it, we can 
measure lots and lots of 

539
00:31:55,300 --> 00:31:58,200
different ways, but as soon as 
you get into the geologic past, 

540
00:31:58,500 --> 00:32:02,900
if you're much above sea level, 
it's really Hard to know how 

541
00:32:02,900 --> 00:32:04,600
high. 
So for instance, the argument 

542
00:32:04,600 --> 00:32:09,800
about the Sierra Nevada, if the 
Sierra Nevada is Young, and 

543
00:32:09,800 --> 00:32:13,300
we've created a young mountain 
range by removing dense material

544
00:32:13,300 --> 00:32:15,500
at the base of the crust. 
That's important to know because

545
00:32:15,500 --> 00:32:20,400
it's telling us about a process 
that we only see hints of in 

546
00:32:20,400 --> 00:32:23,700
other places, that could be very
important in contrast, if the 

547
00:32:23,700 --> 00:32:27,700
range is really old, if it's 
been high, say 40 million years 

548
00:32:27,700 --> 00:32:31,700
ago, it was really high, then we
have a problem that we need to 

549
00:32:31,700 --> 00:32:34,100
To understand how the range 
could stay that high. 

550
00:32:34,100 --> 00:32:37,800
Well things were changing so 
dramatically in the upper mantle

551
00:32:37,800 --> 00:32:41,900
and lower crust underneath. 
So we look further afield, 

552
00:32:41,900 --> 00:32:44,100
there's arguments about the 
Colorado Plateau. 

553
00:32:44,400 --> 00:32:48,500
There's arguments about the 
Rocky Mountains and amazingly. 

554
00:32:48,500 --> 00:32:51,100
There is an argument about the 
high plains, which are here, 

555
00:32:51,100 --> 00:32:55,000
east of where I'm sitting in 
Boulder Colorado, you do are the

556
00:32:55,000 --> 00:33:00,000
High Plains High where they high
60 million years ago or have 

557
00:33:00,000 --> 00:33:04,100
they just gone to their And 
elevation making Denver the mile

558
00:33:04,100 --> 00:33:09,500
high city 5 million years ago 
and again knowing which of those

559
00:33:09,500 --> 00:33:13,700
is really the case or something 
in between is telling us about 

560
00:33:13,700 --> 00:33:18,000
very large-scale Earth processes
that they're not contradicting 

561
00:33:18,000 --> 00:33:20,800
plate tectonics but they're 
expanding upon it. 

562
00:33:20,800 --> 00:33:25,300
We're learning about processes 
that we don't really have a grip

563
00:33:25,300 --> 00:33:28,000
on it present. 
It's really intriguing because 

564
00:33:28,000 --> 00:33:32,700
when you think of large flat 
areas, At least naively. 

565
00:33:32,700 --> 00:33:37,000
I would think of a flood plain, 
which would be very low because 

566
00:33:37,000 --> 00:33:41,400
it's got water flooding into it.
And depositing, it or perhaps 

567
00:33:41,400 --> 00:33:44,300
something like Tibet Plateau, 
which is very high because if 

568
00:33:44,300 --> 00:33:47,000
you have something like some of 
the processes you are just 

569
00:33:47,000 --> 00:33:51,300
talking about. 
Making that Region anomalously 

570
00:33:51,300 --> 00:33:54,600
High although perhaps not on the
same scale as the high plains so

571
00:33:55,000 --> 00:33:58,900
are you thinking that there 
might be yet some completely new

572
00:33:59,200 --> 00:34:02,700
process at work here? 
It certainly looks like there's 

573
00:34:02,700 --> 00:34:06,700
got to be something very 
unusual, the kind of processes 

574
00:34:06,700 --> 00:34:09,300
feel. 
For instance, dripping off the 

575
00:34:09,300 --> 00:34:12,000
lower crust and upper mantle 
like we see under this year in 

576
00:34:12,000 --> 00:34:16,300
Nevada, the scales of the high 
plains are too large, that's not

577
00:34:16,300 --> 00:34:18,800
a process. 
That works at the scales. 

578
00:34:18,800 --> 00:34:22,300
We see of the high plains, we 
have hundreds of kilometers of 

579
00:34:22,300 --> 00:34:24,600
gentle gradient. 
Going down from the Rocky 

580
00:34:24,600 --> 00:34:27,600
Mountains down towards the 
Mississippi River. 

581
00:34:28,400 --> 00:34:34,600
So it's requiring something 
novel and ideas range from large

582
00:34:34,600 --> 00:34:38,500
scale flow in the mantle having 
either pulled everything down 

583
00:34:39,199 --> 00:34:43,500
and piled up sediment and then 
pushed it back up to ideas about

584
00:34:43,500 --> 00:34:46,199
changing the character of the 
mantle over very long 

585
00:34:46,199 --> 00:34:50,100
wavelengths by adding some water
and creating less dense minerals

586
00:34:50,100 --> 00:34:54,000
in the mantle to a kind of nutty
idea that we've put forward a 

587
00:34:54,007 --> 00:34:58,100
few years ago where the water 
coming off of the old laramide. 

588
00:34:58,200 --> 00:35:01,600
Slab came up actually through 
the metal and made it into the 

589
00:35:01,600 --> 00:35:04,300
lower crust. 
Where the lower crust previously

590
00:35:04,300 --> 00:35:08,000
had been rich in Garnet that. 
Garnet, would retrograde under 

591
00:35:08,000 --> 00:35:12,700
those conditions into less dense
minerals and produce a very 

592
00:35:12,700 --> 00:35:16,300
broad uplift. 
So you know, these are the hooks

593
00:35:16,300 --> 00:35:19,500
that I think those of us in 
doing research really look 

594
00:35:19,500 --> 00:35:23,200
forward trying to look for the 
things that you can't really 

595
00:35:23,200 --> 00:35:25,800
explain easily with the current 
Paradigm. 

596
00:35:25,800 --> 00:35:29,900
And I think the high plains 
These are really stupendously, 

597
00:35:29,900 --> 00:35:32,200
dramatic, example of that. 
Because a big difference with 

598
00:35:32,200 --> 00:35:34,700
say, the Tibetan Plateau is the 
Tibetan Plateau. 

599
00:35:34,700 --> 00:35:37,700
There's a tremendous amount of 
deformation and crustal 

600
00:35:37,700 --> 00:35:40,600
thickening. 
There are thrust faults all the 

601
00:35:40,600 --> 00:35:44,600
way across the Tibetan Plateau, 
the high plains are under 

602
00:35:44,600 --> 00:35:47,600
formed. 
There's no crustal, shortening 

603
00:35:47,600 --> 00:35:49,500
by thrust. 
Faulting, there's been no 

604
00:35:49,500 --> 00:35:53,200
physical deformation of it, the 
oil geologist who work across, 

605
00:35:53,200 --> 00:35:56,500
it is practically a layer cake 
of sediments that have 

606
00:35:56,500 --> 00:36:00,000
accumulated over the past. 400 
500 million years. 

607
00:36:01,000 --> 00:36:04,900
So it's the kind of place where 
we learn new things about how a 

608
00:36:04,908 --> 00:36:08,400
planet can actually operate 
Craig Jones. 

609
00:36:08,500 --> 00:36:11,900
Thank you very much again. 
Thank you very much for having 

610
00:36:11,900 --> 00:36:16,100
me for more about geology, b, as
well as pictures and 

611
00:36:16,100 --> 00:36:20,700
illustrations, that support this
podcast, you can go to geology 

612
00:36:20,700 --> 00:36:22,300
B.com