Wednesday, July 17, 2019

--- How big is Creation Rock 2 ---

Frankly, I have no idea.

I've seen two websites that have the same statement, that both Shiprock and Creation Rock are 300 feet tall...but they're different heights. I've also seen that they're both taller than Niagara Falls.

Actually, it's hard to figure out which rock is Shiprock and which is Creation Rock, as this article at the Red Rocks Park website explains.

And obviously my survey wasn't correct, though I'm not as bothered about that as some might expect.

Success is an American ideal. Researchers rarely publish reports on failed experiments despite most books on research design encourages researchers to do so.

You often learn more from a well designed failure than you do from a success. A success gives you an answer. A failure gives you a bunch of interesting questions, such as, "What went wrong? Was my study design flawed?" "I was expecting this to work, it should have worked, why didn't it?"

In 1887, Albert Michelson and Edward Morley wanted to study the "stuff" that light waves flowed through. They set up and experiment that shot a stream of light in two different directions, one at a right angle to the other. They wanted to measure the difference in the speed of light through the paths. They were sorely disappointed when there was no difference.

The problem was that light doesn't propagate through "stuff" like sound or water waves, and this failure started a line of study that lead quickly to Einstein and special relativity.

So, I learned some things from my "failure" and I'll let you in on those things. And, one of the great things about adventures vs. studies is that adventures have a focus surrounded by lots of other "stuff".

I knew that Red Rocks had a concert planned that night (summer's like that at Red Rocks) and that I needed to do what I was going to do before 2:00 afternoon, so I hired a Lyft and headed straight there. The driver let me out at the Trading Post Trail trailhead.

I was delighted by the diversity of plant life on the trail.

                                                   [White Anemones and Golden Asters]

I was rather concerned by the many signs that urged visitors to stay on the trail. I certainly understood the reason - there are delicate plants and animals that live at Red Rocks Park and they don't respond well to crowds tromping all over them, but that was going to interfere with me finding a site for my survey.

As for the plants in the above photo, the anemones are easy to identify by their simple (but often brightly colored), five petaled flowers and deeply lobed leaves. The asters are a little more difficult but many similar flowers have more irregular petals and/or broader central disks.

In contrasts to the tiny flowers are the gargantuan rocks in the park. Red Rocks is justifiably famous for the huge natural amphitheater, home to internationally attended and broadcast performances, but the park itself is a geological wonder.

                                                                        [Big rock]

As the Pacific Plate crashed up against the North American continent, pushing the Colorado Plateau up to form what would become the Rocky Mountains, land around the edges were severely twisted and buckled. These layers of sediments are often tilted to right angles to the rock to the east and are sometimes turned over completely. There's evidently some debate as to whether the rock is sedimentary sandstone or gneiss. In support of the frustrated geologist that snorted and corrected me when I called the Red Rocks "sandstone", rocks this twisted are usually considered metamorphic and, therefore, gneiss. Regardless, the red is prominent and is caused by the same thing that makes old iron red.....rust.

                                                                 [Slanted rocks]

In the photos above, the big rock center stage is my target, Creation Rock. It's the largest of the three massive rocks that make up the amphitheater.

Although Red Rocks Park is the most famous display of these tilted Goliaths (and, in my estimation, the best), there are certainly others. Technically, they are called the Fountain Formation. They stretch through Wyoming and Colorado. These photos bear a strong resemblance to the Flatirons just outside Boulder, and for good reason since the Flatirons are another example of the Fountain formation. Other famous outcroppings are the Garden of the Gods in Colorado Springs. Other instances are the Red Rocks of  Eben G. Fine Park in Boulder, Roxborough State Park, and Red Rocks Canyon in Colorado Springs.

Here are some tiny blue larkspurs.

                                                                 [Blue Larkspurs]

Just behind Red Rocks is Mount Morrison and to the south is Mount Falcon.

                                                      [Mount Falcon from Red Rocks]

I was considering hiking up Falcon when I finished at Red Rocks but the brutal heat of the Colorado summer convinced me that I would be miserable and decided to hold off until cooler weather.

The Fountain Formation marches off to the south between the Front Range and the Hogback ridge to the east, From there to the Mississippi River is grassland plains.

                                                  [Slanted rocks to the south of Red Rocks]

                                               [Wavy rocks on the Trading Post Trail]

I overheard a lady telling a group of children that these waves frozen in stone were the result of erosion from the action of water. My understanding is that the rock carvings of Red Rocks Park and other parts of the Fountain Formation are mostly due to wind erosion. A little further to the north, on Dinosaur Ridge, I over heard a tour guide tell a completely different story.

As incredible as it may be, Colorado was, at one time, covered by a shallow sea. All the dinosaur activity in the area were huge beasts sunbathing at the beach (or maybe a marsh). This was before the Colorado Plateau was uplifted. So, these waves, frozen in rock were not due to erosion, but deposition - sand deposited by the gentle wave action of the inland sea, then covered by more sediment, packed down, and turned into stone under great pressure until they were uncovered millions of years later by the wind. And if you've been in any of the downslope winds in this area, that won't be a great stretch of your credibility.

                                                                 [Jumping cholla]

This is another good reason to stay on the paths at Red Rocks. The Jumping Cholla is notorious for reaching out and touching people. Still, these (cactuses) are still my favorite wildflowers and Denver area, being desert, is a natural habitat for them.

At the end of the Trading Post Trail is, of course, the Trading Post, which is also a museum of pop music. It is located to showcase some of the big rock formations, such as this huge column.

                                                                 [Big rock column]

Many of the formations are named, but there are so many....I can't find a name for this one.

I looked around the Trading Post and asked a couple of staff some questions verifying that I was going to have problems finding a place to stretch my 100 foot cord. I finally settled on a line of sight near the Trading Post for my two locations. The first is at a fire plug across from the building. Here is Creation Rock from that site. The road branching off to the left is Shiprock Road.

                                                       [Creation Rock from Site H]

The other site was a little ways up Shiprock Road to the south. I could just sight the summit of Creation Rock above the boulders to the west of the road.

                                                          [Creation Rock from Site G]

Since I knew that I would have problems with this data, I started looking for ways to double check my work, multiple ways of estimating bearings and distances. I measured the distance between my two sites using an app on my phone called Altitude (created by PyGDroid and available on the Google Play Store). The app calculates distance traveled using GPS. I found the distance between the two sites to be 0.05 miles. That converted to 264 feet and, later checking Google maps for a distance, I found it to be about 257 feet, which is the distance I ended up using.

Here is a shot from the Trading Post back down through Bear Creek Canyon where Morrison is situated. The lakes in the distance  are the Soda Lakes at Bear Creek Lakes State Park. I'll get to that later.

                                                    [Bear Creek Canyon from Red Rocks]

My altimeter reading told me that Site G was about 40 feet above Site H and I could look down on top of the tall Trading Post building from Site G, so I felt pretty confident with the phone app.

I went to work getting bearing readings from my surveyor's compass and I checked them to the nice north to south bearing of the Front Range. My bearing from Site G to Creation Rock was 313 degrees and, since I was east of the summit, that made sense. The north to south line is 360 degrees and everything to the west would be less than that. Sighting back to Site H, I found a bearing of 72 degrees. Since it was east of the north - south line, it should have been between 0 degrees and 90 degrees, and it was. I could add the difference between the bearing to Creation Rock and the north - south line (47 degrees) to the 72 degrees west to find the angle G, which was 119 degrees.

The bearing from the fire plug to Creation Rock was 257 degrees and the bearing back to Site G was 290 degrees - both were west of the north - south line, so those made sense and I could subtract them to find angle H, which was 33 degrees. That felt right. The angle of inclination from G to the summit of Creation Rock is 16 degrees and that from H to the top is 15 degrees, so I had the distance of the base of my triangle (side e) and the angles G and H, and the angles of inclination. That was what I needed. Here's my trigonometric plan diagram again.

The problem was that I had no idea what the elevation difference was between me and the base of Creation Rock. I was going to calculate the height of Creation Rock above me, not above its base. I didn't expect to be close. Well, I went with it and started back down Trading Post Trail to Morrison.

                                                     (From Red Rocks to the south]

On the way, I saw this patch of prickly poppies. That was the first western wildflower to confuse me after moving from Alabama. It looks like a thistle until it blooms and, then, that's certainly not a thistle bloom.

                                                                 [Prickly poppies]

And there was this paintbrush flower.

                                                                [Paintbrush plant]

And this rose.


I didn't know that roses grew wild in Colorado.

Back on the road, I saw these huge sweet pea plants and milkweeds

                                                                    [Sweet peas]


I've mentioned that milkweed is one of my favorite wildflowers. I think that it grows over most of North America. I would occasionally see it in the South but it seems to like cooler climates. The further north I would travel, the more milkweed I would see.

We had a few stalks trying to grow in our back yard but one of the recent storms took them out. I was a little disappointed, there was a big flower head developing on one of them, and they are the only plant that Monarch butterflies will lay their eggs on, but then I saw all these plants in Morrison and felt better about it. I can enjoy other people's milkweed.

After a milkshake at the Mill Street Eats, I headed down Bear Creek Trail. It's been awhile and, after all, this is the Bear Creek Commentaries. I felt the need to reconnect. I also wanted to get a shot of Red Rocks Amphitheater from Mount Carbon to put it in perspective.

                                                                [Mount Carbon]

I found Bear Creek Lakes Park just as I left it, a blazing expanse of open space. By the time I reached the top, I was ready for a snack, water, and a long rest.

                                                       [Denver from Mount Carbon]

Here's Red Rocks with a magnification of X2. It may not seem so big but compare it with the prominence of Mount Morrison behind it (741 feet) and consider that this photo was taken from 3.9 miles away.

                                                       [Red Rocks from Mount Carbon]

My preferred route up or down the eastern flank of Mount Carbon is the Mount Carbon Loop Trail, which has great views of Denver and Bear Creek Valley. It also has a diversity of wildflowers such as this prickly pear cactus, certainly not a rare plant, but, like all cactuses, has an intricate, silky, showy blossom.

                                                               [Prickly Pear Cactus]
By the time I walked around the Fox Hollow Golf Course and reconnected with Bear Creek, I was whipped and spent some time on the shoulder of the trail. I would have used the bench across from me but Colorado, evidently, does not believe in shade and most park benches are situated to catch full sun. (what is that?)

Still, it allowed me to catch this bug's eye view of the grasses that line the trail.


I made it to Wadsworth Boulevard and chugged down two cans of Arizona Green Tea before calling a Lyft taxi to return home.

Now....the calculations.

Here's the geometry again.

 I know that angle G is 119 degrees, angle H is 33 degrees, and the length of side e is 257 feet. Angle E is easy because the sum of the angles in any triangle add to 180 degrees, so 180-(119+33)=28 degrees. That makes sense. Angle E is the angle between the two sites as seen from the top of Creation Rock. They are only separated by 257 feet so the angle of separation should be sorta small.

Since I have all three angles in the triangle EGH and the length of the base side, I can now use the law of sines to figure out the other two sides.

                                                                      [Law of Sines]

The length of side g, the distance from site H up to the top of Creation Rock, works out to be about 479 feet. The length of side h is about 298 feet.

Now, the diagram is a little misleading here. The point F looks like it's on the line GH, but it's not - it's way back behind the line. It is the point directly beneath the summit of Creation Rock. I calculate the length of line EF by either looking at the right triangle EGF or the right triangle EHF, and I will do both because the difference I come up with is important.

Right triangles are easy. In this case, I have the long side, the hypotenuse of the triangles (sides g and h) and the angles of inclination at G and H, and I want the length of the opposite sides. That's actually the measures that I want because it's the height of Creation Rock from the summit down to the level of my surveying sites. In other words, if I find the sine of one of the angles of inclination from the site up to the top of Creation Rock and multiply that by the distance from the site to the top, I'll have the height. I use my spreadsheet to calculate the sines and I come up with 82 feet (from site G) and 124 feet (from site H).

These results are certainly far short of the actual height of Creation Rock, but do they make sense?

Well, the difference between the two calculated heights is 42 feet. That's the difference in altitude between Site G and Site H. To walk from the Trading Post to the fire plug at site H, I had to walk slightly down the hill, then to walk to site G I had to walk around and above the tall Trading Post building. I could look down onto the roof. 42 feet works.

Also, I pulled a topographical map from the Internet site:

The contours are 40 feet elevation apart.The contour on level with the Trading Post seems to be about 3 contours above the base of Creation Rock, so that would explain the discrepancy between my measurements and the reported 300 foot height of Creation Rock. It looks like site G was about 3 contours, or 120 feet above the base. Even with that, I was off, so, no cigar.

Most likely, distance e was my most inaccurate measurement. The compass bearings seemed to agree well with the line described by the mountains.

But it was a fun and scenic adventure, so I'm happy.

The methods I used have served me well in the past. This trip was plagued by several unexpected problems - difficulty in finding two good sites being a major one. You may be able to use trigonometry in your own projects. One suggestion is to avoid angles that are too steep (within between 70 and 110 degrees) or too flat (between 340 and 20 degrees.) At these angles, a tiny difference in slant can make a huge difference in the value of a trigonometric function, or vice versa, so that can throw your precision off considerably.

There are a lot (!) of resources on the Internet about trigonometric functions and surveying methods. I can recommend CK12's Trigonometry textbook, 2nd edition by Lori Jordan, Larry Ottman, Brenda Meery, Art Fortgang, Andrea Hayes, and Mara Landers  and you may want to look at their other offerings at:

By the way, according to the topographic map, Creation Rock is either 280 feet or 400 feet tall according to where you consider the base to be.

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