Centennial is a great time to look back a hundred years to the park,
hundred sixty years to some of the early adventures and explorers, and
it's also a good time to look forward. I think that's the benefit of Of
Looking Back is to think about lessons learned and where we're headed. So
I want to do that. Uh, today, with respect to geology, um, how many
geologists out there?
Okay, not enough.
Geology is marvelous. Science study of Mother Earth. What a good planet we
live on And what a worthwhile task to try and understand the processes
that go on on the Earth and her history. And so we do that with various
tools, the most modern tools and also rather, uh, boots on the ground sort
of efforts. And I want to say that the geologic map we've been talking
about mapping this session fantastic presentations, geologic map adds
another dimension or two, it adds. It takes a a, uh, topographic map or D
M, which is itself. We've been hearing and endeavor to produce accurate
ones and beautiful ones. And it adds to it a time dimension because the
rocks that air at the surface of the Earth each have their own age in
history. And it also adds a depth dimensions because they layers air,
horizontal and upper part of the Grand Canyon there tilted in the Grand
Canyon Super Group. And they're folded, uh, wildly in the basement. So
this this map here, which, by the way, uh, hon to knit all the bestselling
geologic map of all time now out of print. It's a tragedy. It's out of
print, but it gives us an opening for next steps in terms of mapping. So I
want to kind of go back to the beginning. Uh uh, This is probably not
comprehensive, but it's my perspectives on stages that we've come through
in terms of geologic mapping.
I've got to do scales for a minute, so I don't know if you've noticed, but
if you go out and walk on the surface of the earth, there's something
they're everywhere.
Yeah, so? So that's your job as the geologist. You have to say what it is.
And you also have to say how it got there, how its orientation is a
little bit about its age, and you could do it at a variety of scales.
Here's a Here's a geologic map of the United States. A beautiful thing by
the U. S. G. S, uh, wanted to two and a half million. Not not ex,
exceptionally detailed, but a really nice view of our whole, uh, country.
And the colors represent different rock units of different ages. And you
, Khun, dive into that and learn the history of the US Here's the Arizona
map one to a million state map And so you can put more detail on these
maps one to a million than you can in two and a half million. But you
don't have the whole big picture. So this is going to be kind of a theme
to trade off. Do you wantto get the whole picture, or do you want to see
the detailer, your forest trees kind of person and, uh, upper box? There,
the Grand Canyon. I just want to highlight Georges nine quadrangles. That
air shown they're in in the black boxes. Now we're coming right to the end.
Really? Georges just finished these efforts of putting together the
picture of those nine quadrangles that encompass what we think of now is
the Grand Canyon, the entire Grand Canyon. So I'LL get back to those but
those air one hundred thousand one toe one hundred thousand.
A lot of times the mapping is done at much more detail than that, and you
compile them at one hundred thousand. So looking back Oh, let's see. One,
two, sixty two, five That's the dragon map. The blue map, Uh, hunh tune.
And when Rick Billingsley maps in the Western Grand Canyon one two. Forty
eight thousand. And then the Timmins and Carlstrom map over there on the
right is the first one of these one to twenty four thousand maps that we
have out on behind. But let's go back a little bit to the first one that I
know of. And people have shown this one from the IVs expedition. Beautiful
map. I got this from from Matt. Thank you. But you notice I put the rocks
in the bottom so you could see them a little better. These guys did an
amazing job for the time. And for that, they struggled to be out here. And
they identified the different colors represent different ages of rocks.
For the most part, they got it pretty good. They got, uh, tertiary and
critter Nery Volcanic sand. They got the basement. They thought the, uh
the, uh the Grand Canyon supergroup was celery in. But, uh hey, that's not
too bad. And And they thought the rim of the canyon was, uh, Pennsylvanian
instead of Permian. But But they had fossils. They look for fossils. They
did a great job of figuring out basically what the rock types were. Ah,
and you know the theme about thes topographic maps that we've been hearing
about? I was I've been thinking about it as a as a here. These talks, we
just call him basement way. We go out there because we're trying to put
the rock types on these topo maps. But you can see if you look at this
history how in a new set of Topol has come along, the geology takes off
because you have a better way to locate yourself on the map, and you can
show more detail. So this is the This is Dutton's topography pretty good
that this is actually almost sixty one sixty three thousand map. It's a
pretty good topography. Er, this is from the Dutton Folio. You can see the
Grand Canyon looks like it should now, because Powell has been through.
They have the the different ages. The grand staircase that's the most
Sheldon just depiction of the grand staircase as the Mesozoic Rocks are
being stripped back off the blue Kaibab limestone by erosion and you see
the volcanic fields a really nice map. In eighteen eighty two, he had
different scales, all within that same folio. This is more or less one to
two hundred fifty thousand in that same folio showing a little more detail
, and so ages aren't right. But we're beginning at this point, uh, one
hundred fifty years ago to know the basic rock types of fossils in them
and the distribution of rock layers. Um, here's the math of seventh
topographic map we've been talking about and, uh, write it as this was
being produced. Along comes Levi Noble, who actually is putting geology on
that new uh, Shenmu Quadrangle. Matt. And so he's so he he worked a lot on
the grand came supergroup the tilted layer in the lower right and defining
faults. And he also clarified quite a bit about the strategic forgetting
the ages and the nomenclature. Uh, better. By about nineteen thirty five,
the rock names, for the most part, had been kind of settled. Here's a map
from Maxim nineteen sixty one nineteen sixty eight two versions. Geologic
map of the Bright Angel Caught. He was actually had a title of
collaborator at large
with the park, so I don't know how he got that, but anyway, the park needs
to think about. And of course, Edie McKee was a park naturalist. And as we
look forward, we look back and say, OK, what's the park's role in any of
this? And hopefully that will be improving and in subsequent years. But
this is this an elegant geologic map. You can see the fault line fault
lines along the a bright Angel fault Northeast Trending and Maxim's Rock
column. Uh, from nineteen sixty one, you know, the layers in the right
thickness is in the ages, and the names are pretty far along that that
rock column has been reproduced again and again in different iterations
for for a lot of years. And I gave a talk last week about depicting
geology in terms of rock columns, and that was a very influential one
cross section at the bottom. The geologists always tryingto map what's on
the surface and then use the measurements that you take to interpret what
is underground. And so the cross section of the bottom shows the three
sets of rocks. The basement rocks at the bottom, the tilted Grand Canyon
Super Group and the flat line Paleozoic rocks on top.
No, Again a step forward in terms of mapping the photographic methods. Um
, and we're taken advantage by by people. This is kind of interesting. I
ran across this in our library. You probably have it here. But Maxine in
nineteen sixty nine did what he called a preliminary geologic maps, and it
has almost no new detail on it, but he was obviously starting big to do.
What then was taken over by Peter Hunt Tune and George Billingsley and
other collaborators. And these are the, uh this is, um what is this? This
is, uh oh. Here's Maxim's map in two sheets, following on the new
topography and trying to compile everything he could with not much detail
in the West. But this map this way called the blue map, or sometimes
called the dragon map when they heard that term for this map. The dragon
map. Okay. As you look at it, do you see a dragon or not?
Okay. This kind of an argument between me and my wife? No, about the
dragon. Okay, so I want you to think where you think is the mouth of the
dragon. And, uh And what are those two things sticking up, pointing to the
right. And and here's the two interpretations. I won't tell you whose is
whose. But there's the two interpretations of the dragon map, so I don't
know which one was yours. Do you think that the two things sticking up for
the mouth, how are do you think they're the ears
anyway? So that's that's a diversion, but
best selling geologic map of all time. And you know, one of the successes
of this map, Uh, I give to the creators of it George Peter Hunt tune, and
they brought in people who wanted to work on different parts. And so the
early versions, Let's see what I have. I can remember all the alterations
, but this is the nineteen ninety six version that I was privileged to be
co author on because we did the basement rocks and prior to that had been
a different group that had, uh, had their basement lines put on there
Jim Sears map. The supergroup Georges always concentrated on the street,
Eager fever and everything else. Peter Hunt Tune did a fantastic job with
faults. So this map represents not only the best knowledge at the time,
but, uh, team effort to put together the best view of Grand Canyon geology.
Then they extended their work to the West with the I like to call these
the Hun tune at all brown maps because they didn't color him. And, boy, do
I like that when I'm out hiking are working with students. I can see the
Topal lines. But then George came along and Karen when Rick and did the
maps and color for the U. S. G s o. Same scale. One to forty eight
thousand. Quite good detail and covering really the Western part. So
here's Georgia's effort, uh, following on from that, each one of these
geologists myself included, George included, um takes advantage of all
that hard work from previous workers. It's a lot of work to hike through
the Grand Canyon. If you're hiking, it's a lot more work. If you're
mapping, trying to look behind each rock, what's over here? There's
something on the surface of the earth everywhere, and you have to go look
so it's a lot of work. I've had a lot of students involved in a lot of phD
students. I've been mapping in the Grand Canyon geologic mapping for
thirty five years. George is like fifty five or something, so he's my my
hero. But this is the Grand Canyon sheet, one of nine sheets. And if I
tried to show you the detail, it's in there. We could zoom into whatever
your favorite places and find out what the faults looked like in the ages
of the Rocks. But this is this is the big picture,
and I've kind of gone the other way now in my present emphasis. And that
is, I want the big detail on a smaller. So this is Mike Timmons, phD
student of mine, and I put together this Eastern Grand Canyon map one to
twenty four thousand, and so that piece of paper that you get it on, it's
about the same size, but you just have a lot more detail. So that's a
That's kind of the effort that I've been doing. This is the Timmons and
Carlstrom map and a lot of stuff on here on all geologic maps. There's a
explanation of the rock units with the oldest the bottom. There's a rock
column and a Time column to showyou ages and rock names. All those cross
sections. You know you make slices and think what the three D geometry is
of these rocks. And so it's a big effort. So that's a That's a phD student
effort with a lot of support from multiple collaborators, because that's
the way you get the best geology. Here's the cross section. There's a fun
one because you may know the Butte fall, which is that big fault. Angled.
Well, there's four of them there, but the second one from the right, the
beautiful. And if you look, uh, at the bottom brown layer, you can kind of
find one of those Browner's you, Khun Trace from the lower left across the
fault of the upper right. You can see that the left side is down, right? I
agree with that. Then if you look at the Kaibab and all the Paleozoic
rocks, they're kind of projected into the air. You see that the left side
is up, so you see, do you see what I'm saying? That fault the geologist
really screwed up. I didn't even know which way the fault moved. No,
that's not true. What's true is that that fault was a left side down fault
in the pre Cambrian huge amount of displacement that allowed these basins
to develop the to our group. And then later on, when the content was
squeezed, that weakness, that zone a weakness got inverted and pushed up
the other way. So it's called fault reactivation. It's a nice story of how
a weakness in the earth can be reused again and again. If you break your
arm, you might break it again at the same place later on. So I just want
to touch on a couple of topical things as we map. We're interested in the
history of the Earth, and we're interested in in the record everything we
can learn from these rocks with the rocks of the historians were taken
taken. The record, Uh, this is Powell's drawing slightly modified of the
three sets of rocks, and if you look on the right from the Timmins and
Carlstrom map, you can see if your eye if you get good at reading maps.
You can see the three dimensions, and you can see the ages all in that
colors of that map. And it won't go through it in detail because I just
want to highlights some of things we've learned from thirty five years of
mapping. Here's here's what I George, Here's what I want to do before I
retire and get those. Uh, you know most the mapping is done, so we just
have to pull together the upper granite gorge as spread. ILCs. PhD Middle
Granite Gorge. That's several students, the lava damn work from Ryan Crow
and the first thing I did was the Lower Granite Gorge, and it's still not
published yet, so that's terrible, but that those are going to get done at
one twenty four thousand. And so here's Here's a an example of a geologist
out there, uh, trying to put lines on the map, which rocks air where the
red on the map on the right, the red stuff for the pigment ice. If in case
you're wondering, so you do some sky mapping where you sit there and
sketch just like maths and Evans. But then you go put your nose on the
rocks and identify it and take it back to the laboratory and date it and
study it in various, which weighs so these air. These will be one to
twenty four thousand detailed maps, but I'm just showing him in cartoon
form and sometimes geologist like When I started, I didn't care at all
about any rocks except the basement rocks so we would blast down the river
till we got to the pre Cambrian. I just didn't care about any of those
other things and how the canyon got there. Who cares? You know, I was
interested in that one, said Iraq. So you could make a map that just shows
what you think the basement is doing. And that's what this is for the
Lower Gorge. And there it is for the upper gorge, with folds and foley
ations and sheer zones, and the record of how the North American continent
was first assembled almost two billion years ago. So that's a story in
that rock layers. Or when Mike Timmins came along, I said, Okay, I'm
pretty much done with the basement Tiptoe haven't published yet, but let's
do the the super group so we said, OK, let's peel everything off, get rid
of that ugly basement and just show a map of the Grand Canyon supergroup.
Oh, this has the basement in it, too. But the supergroup is green and dark
purple. And Powell, of course, saw the UN car group along the river the
green color there. But there's no record that I know of that he saw the to
our group. It was until Walcott came along, where he I went back in there
and he thought he was going to find a Burgess shale kind of record in the
wall in the to our group, which didn't come out. But he did find these
millimeter size microfossils that he called Chu Arias. So we have a rich
record of Walcott paleontological work in Eastern drinking. So thinking
forward about these maps, I'm just you know what happens when you come at
a time in your career when things were changing, We we heard about that
from from Tom and you want to adapt and you wantto pull it in together and
so visualizations that we're gonna be able to do, uh, increasingly is a
chat or challenge, though, because not only is the topography challenge,
but all these layers of different rock types are challenge. And then this
is the thing that's really challenged. Zoom ability. Now Google Earth
weakened. Zoom in and we can see more and more detail a Z zoom in. Well,
that's the future geologic mapping. But we have to have every one of those
scales well understood for that scale. You can't show everything on on the
the big regional maps. Er and so here's that you see the little red box
there. So this is already the one twelve thousand detail, one to twenty
four thousand detail, and then that map showing the rock types along the
river in more detail. So I don't know how we're going to quite get there,
but we will. And then these beautiful maps, these that we saw, how they're
presented, we can use him for Earth, science, education, science, literacy
and actual, uh, important discussions about park Resource is So this is
from Laurie crosses talk that she's giving those we take. Take that. A
bleak view. We put faults on there and we say, Okay, where did the water
moved? Where does water move from? The north room snowpack, intothe
springs and across the canyon. So we can begin to convey to, uh, park
officials and resource people a little bit about how the geology affects
water resource is, and hence the and water quality, and hence the future
for park development.
So this is the park now that's Ah, Park now goes from Lake Powell, Toe
Lake Mead and George has a map of it one hundred thousand, which a lot of
which it would take quite a bit of enlargement because we've done in
detail. But we have this chore now of portraying that and educating the
public that's increasingly sort of resistant tto understanding concepts of
time and and science. And so geology is a way to hook people in the Grand
Canyon way to hook people in. And, uh, I wantto implore all of us to do
what we can tow. Add science literacy to this thinking of the mapping
mapping conference. So one hundred sixty years geologic mapping geology
has been in the forefront of Grand Canyon science for one hundred sixty
years. New geologic mapping often follows. These developments in
technology is like topographic maps and now, with digital media it's
goingto be the same. Well, it goes hand in glove with science questions.
The ages of the rocks, the layers, the new dating, uh, and how to manage
Resource is. And here's what I want to see near future mapping. I want to
get those one to twelve to one. Twenty four thousand maps finished that we
have the mapping done from this hard student work and get the fault man at
work Networks mapped better because that's the water pathways we think in
large part, Um and then howto have tio display them. You know, there's no
geologic map at the Yavapai Geology Museum and also the Grand Canyon. Uh
uh, GCC Grand Canyon Conservancy doesn't sell geologic maps anymore.
They're big, and they how do you sell him? Their hard to hard to stack in
the back and keep rolled and whatever, but we need to get jolly geologic
maps back out into the public. I think people love them. They're beautiful
and figure out how to do that and, uh, use that away as a way to work on
science literacy for this six million people a year from all over the
world. So I think we have a task to do. Thanks very much.
We've got a few minutes. Does anybody have any questions? Geology
questions? Got a few minutes.
Could you describe rocks that you have dream all the way to the base?
Yeah, we can just forget the break and I'LL go.
The basement rocks are almost two billion years old. They represent the
formation of the convent. The Tilted Rocks Grand Canyon supergroup ranged
from about one point two five billion to about seven hundred million, and
they record the assembly and break up of the supercontinent of Road India
from the perspective of a Place Grand Canyon area that was inside of the
supercontinent. So it's a sedimentary record. The last flat lying rocks
started about five twenty and go two to seventy million. So that's most of
the Paleozoic, or old life period. The dinos Rocks of the dinosaurs. The
Mesozoic have been stripped back off the rim of Grand Canyon and the
Cenizo Act, the era we're in now. There's a few little scabs and intra
using rocks of assaults and Traver teens around. So we have. We have an
amazing record of the last half of Earth history, about two billion years
I have a question that was like
for the for the layers of the soils in the Grand Canyon? Or guess just in
geology in general. Were you saying, uh, you guys have to come guess Or
how does how does that work for figuring out all of what's underneath? Do
you have specific tools for that? How does that work? Yeah, How do we How
do we time? Rocks basically, is two ways relative ages. I'm older than you
, so we know that. And, uh, and then there's absolute ages. Would like to
know how many years old you are and how many years old I am for that. We
use radioactive clocks, radio metric dating, and there's a variety of
methods, and they test each other on duh. We're getting much more refined
absolute ages or or numerical ages for rocks. Using systems like uranium
lead decay in circon crystals, for instance. But the fossils that come
from the relative dating huh, are the way we always start. And so the
bottom sedimentary layer his older than the one on top of it, and then
they get younger as you go up, and then the fossils change as life on
Earth evolved through millions and millions of years. So the fossil record
was the way the geologists originally set up the geologic time scale. And
now the dating is getting very precise about when the fossil transitions
took place.
Thank you.