Tag Archives: Geology

Kodel’s Canyon

Geologic Time Scale

Growing up in Fruita, Colorado on Colorado’s Western Slope I had rich opportunities for exploration.  The area is amazingly diverse, offering the 10,000 foot elevation Grand Mesa to the east, the stark Bookcliffs to the north, and the spectacular red rock canyons of the Colorado National Monument just south of town.  All this surrounds the Grand Valley where I grew up. These areas and others were within short driving distance, with the Monument in bicycle range just across the Colorado River.

My friends and I used to take our .22s across the river and assault hundreds of rocks.  Our wandering took us across the National Monument boundary into Kodel’s Canyon.  Nobody went there in those days so we didn’t worry about having illegal guns in the park.  The canyon was smaller than the others, but we had the place to ourselves.  The approach is a deeply eroded plain of Dakota Sandstone from the river to the canyon.  The Cretaceous Dakota grades off to the Mancos Shale of the Grand Valley floor.

Kodel’s Canyon

That Mancos Shale is usually called Stinking Desert by many.  It is somewhat infertile unless well drained, and results in mostly barren gray flats.  Lots of barren gray flats from central Utah to Delta, Colorado.  With water and good drainage to carry the salt away, it can be farmland.  We would leave home on the valley floor and climb into the red rock Kodel’s Canyon.  At the mouth of the Canyon is the Kodel’s Canyon fault, where the Uncompahgre Uplift shoved all those Older Jurassic red rocks above the Cretaceous Valley.

Looking at the Grand Valley from Colorado National Monument

The bottom of the canyon is smooth rounded granite and schist geologists call basement rocks.  They are seldom found exposed on the Colorado Plateau, covered by thousands of feet of sedimentary rocks.  The time gap between those old basement rocks and the sedimentary rocks sitting on them is over a billion years.  It’s called the Great Unconformity, where all the rocks deposited during that billion years were eroded away.  This gap is found in many places worldwide, but there are also many places where the rocks missing in our canyon were deposited and remain to be seen and enjoy.  Think the Flatirons, Red Rocks, and the Garden of the Gods, all Cambrian.  Those rocks sit on Precambrian Gneiss and Schist 1.7 billion years old.

Those old rounded black rocks are great for climbing and we did it.  Today it’s called bouldering.  We didn’t have climbing ropes, so we used our .22s as climbing aids.  Dangerous?  Yes. Fun? You bet.

Among the guys I grew up with, only one had any injury running around across the river.  Jerry had a seriously sprained ankle.  The two guys with him helped him down to the road and help.  He exploited the ankle to excess.  At Boy Scouts we always played Capture the Flag after the meeting.  Jerry would hobble down to get the flag defying anyone to stop him.  I walked over and pushed him down.  I don’t think he ever forgave me.

Terremoto

I was sitting in a building in the San Jose, Costa Rica airport waiting for my luggage when the building shook.  A soccer game was on the TV, and the guys just looked up and grinned at one another.  It wasn’t much of an earthquake, but Costa Rica has had some big ones.  It’s a mountainous country, and in 1991 a big one closed the road and railroad from San Jose to the Caribbean coast for weeks.

Typically, earthquakes happen where tectonic plates collide.  In Costa Rica it is the Cocos Plate diving (subducting) under the Caribbean Plate.  The  Cocos is headed east, the Caribbean is moving west.  The combined motion makes for some real fireworks.  The boundary is marked by a string of Volcanos.  The only active volcano I have visited is Irazu, northeast of San Jose.  It is a big tourist attraction and showered ash on President Kennedy in March of 1963.  I developed more of an appreciation of a volcano’s power when I looked into the crater.

Volcanos and earthquakes release energy on a scale that overwhelms the human imagination.  The nation of Japan moved about eight feet east feet during the 2011 earthquake which caused the tsunami responsible for inundating the east coast of the island.  Sea level rose about ten feet.  Now that, folks, is one hell of a shove.

Economic loss was in the neighborhood of $235 billion, the costliest natural disaster ever.  The magnitude was 9.1, about as big as they get.  Remember the scale is logarithmic, with the amplitude increasing by a factor of ten when moving from number to another.  Thus a magnitude increase from four to to nine is 500 times more intense.  The energy release is not on the order of ten times, but closer to thirty times.  You do the math.  It is enough energy to change the rotational speed and tilt of the earth.

The southern end of our old friend the San Andreas fault is overdue for a major slip.  The northern portion is less likely as several good sized quakes have released much of the stored energy.    Estimates of the magnitude of a big one on the southern segment are in the range of 8.0.   Not as bad as the Japan shake, but enough to more than $200 billion, with major loss of life.  That Los Angeles Basin is full of people and stuff.  A big quake would trap most of the people there with no power or water.  Can you imagine no superhero movies for many months?

Christmas brought me several good books, including one on earthquakes and one on wildfire.  Brace yourself for disaster stories.  What is clear to me from my studies on wildfire and earthquakes is that there is risk to living on this planet.  Humanity only serves to magnify the rise.   We want our surroundings to be fairly steady state.  Not so, the driving force is change.  Whether natural phenomena or human caused. It will all change and then we die.  The key is to make life worthwhile, accepting the inevitability of change.  In the meantime, try to avoid Southern California if you can.

Weird Wyoming

Along with having the entire atmosphere pass through the state in any 24 hour period, Wyoming has some other attributes beside the wind.  I like Wyoming for its diversity and the fact it doesn’t have too many people.  The diversity also extends to the geology. Prairie in the east, Devil’s Tower and the beautiful country around there to some of the most spectacular alpine country anywhere, even if the mountains are lower than ours in Colorado.  Oh, and Yellowstone, our first National Park.

Wyoming Geology

I especially like the deserts, like the Great Divide Basin, aka the Red Desert, a depression rimmed by the Continental Divide.   Yellowstone is the largest and most dangerous volcano in the country.  There is coal, iron ore, oil and gas, uranium, and trona, to name a few.  Those resources are a double edged sword, leading to a boom and bust economy.  Ranching just soldiers along,  but it is a hard way to make a living.

A good portion of the economy comes from Greens (Coloradans, known for their green license plates).  It’s the topography that draws me.  Rivers flowing north, through mountain ranges, fed by hot springs.  A range of hills known as the gas hills, where methane comes out of the ground.  Mountain ranges running north and south as God intended, but the Snowy Range runs east-west and is the boundary between the ancient island arcs known as Colorado and the much more ancient Wyoming Craton.

The Wyoming Craton has some of the oldest rocks in North America, sharing the antiquity with the Canadian Shield.  Ages vary but are around 2.6 to 2.8 billion years old.  The oldest rocks in Colorado are around 1.7 billion years old and arrived as an island arc smashing into Wyoming, much as Indonesia and the Philippines are headed to Asia.

Wyoming has had a lot of activity down deep, shoving mountains up and sliding them around.  That pushing and shoving means areas where oil and gas get concentrated in the bends and corners, thus all the oil patch work there.  There is a lot of coal. The Union Pacific got its coal right near the tracks, and there is a tremendous amount of coal in the Powder River basin.  Coal is out of favor now, so Gillette is hurting, people leaving.

The reason Wyoming got famous is for two reasons, unruly Indians and the livestock business.  There was a lot of Indian fighting in the middle of the nineteenth century, what with the Oregon Trail crossing the region.  When the Indians were whipped, all that empty country became home to cattle and sheep.  The livestock people still hold most of the political power – they also have oil and gas leases, so they aren’t very environment friendly.  Lots of cowboy legends came out of the place.

My favorite things are the rivers running through mountain ranges.  The textbook example are the Wind and Bighorn rivers.  They got their names because early explorers didn’t realize they are the same stream bisected by the Hot Springs Mountains.  The Bighorn flows south through Thermopolis and its hot springs and roses into a beautiful narrow canyon.  The Wind River flows out of the canyon.  The river was there, the mountains came up, and the river (rivers?) stayed in the same place, cutting the canyon as the uplift occurred.

Do I need to say the Wind River is aptly named?  Years ago in Colorado Springs I met a bicyclist doing a ride across the country.  He came across Wyoming.  He looked at me and in awe said,  “The Wind”.  He rode into the wind all across the state.  Another time I was driving from Laramie to Fort Collins after dark. It was Christmas time and the ground blizzard was in full song. I saw a VW bus along the road near Tie Siding. In conditions like that, you stop.  The occupant was from Australia and said “I’ve never encountered weather like this.”  It was around zero with 50 mph wind.  The VW had quit, probably a frozen gas line, and his wife got a ride into town to get help.  Shock and awe.  I just laughed and saw he was OK.  You know about the Wyoming Wind Gauge.  It’s a length of heavy chain hanging from a post.

Jackalope,, Wyoming State Animal

There is usually a Jackalope colony nearby.

There are three books I recommend:

Rising From the Plains, John McPhee; Roadside Guide to Wyoming Geology; and Wyoming Geologic Highway Map

Denver Basin

Denver Basin

The Denver Basin is a deep syncline just east of the Southern Rocky Mountains.  It started around 300 million years ago when the Ancestral Rocky Mountains were uplifted.  A little plate tectonics here, folks.  A tectonic plate is a huge plate of rock slowly moving on the earth’s mantle at or near the surface. When two tectonic plates collide, one of them often dives beneath the other.  As the plate subsides, it runs into hotter rocks at depth.  The subsiding plate has lots of water which lowers the melting point of the rock.  Then things really go on the move.

The subsidence zone, usually along a coastline, gets pretty active, meaning earthquakes, volcanos, and the intrusion of huge blobs of granite known as plutons.  New rock coming in from below means the overlying rocks get uplifted into mountain ranges.  The other side of this mountain building is known as the foreland and usually subsides as its mass goes into the new mountains.  As it subsides, the new basin fills with debris eroding from the mountains.

The Flatirons, Dakota Ridge, the Garden of the Gods, all are built from rocks buried thousands of feet deep just a few miles from the outcrops.  I am sitting here writing atop thousands of feet of mountain debris.

The mountains eventually get hauled away in rivers or dumped into the basin.  This happened twice here in my home country.  The second event occurred at the end of the Cretaceous and the early Paleogene, about 60 million years ago.  Our current Rockies came up, known as the Laramide Orogeny, came up again, and the foreland deepened even more.  It ended up being about 13000 feet deep, filled with the stuff washed and blown off the mountains.

This all took a while.  Rivers formed, seas came and went, and lots of life contributed organic material to the basin.  The result?  Coal, oil, and gas.  The first oil well was in Boulder County, producing from fractured Pierre Shale, which was deposited by an inland sea.  Now this Basin is big, extending into Nebraska and Wyoming.  Huge amounts of oil and gas have been produced, and horizontal drilling and fracking are releasing even more.  The Denver Basin is an oil patch.

Water from the mountains also entered the basin, creating aquifers producing lots of water.  We pump the water and because it is in an enclosed basin, it doesn’t recharge as fast as it is pumped.  Douglas County is going to run out of groundwater some day.  Then the water will have to come from the rivers, and the supply is limited.  Thus, seemingly crazy proposals to pump water from Flaming Gorge Reservoir on the Green River in northern Utah to Eastern Colorado.  Problem: California and Arizona also want that water.

Climate change has the potential of reducing the available water as well, eventually ending population growth.  Amazon, Stay Away.  Mining started Colorado development, and today the money still comes from the ground, but is from oil and gas. As we transition to alternate energy sources, where is Colorado’s wealth going to come from?

John McPhee

John McPhee is my favorite writer.  He writes nonfiction for the New Yorker and has done so for fifty years.  He writes about whatever he wants to.  Alaska, the Pine Barrens, oranges, geology, transportation, and people.  Always, a topic is people.  He decides on a subject and searches out people engaged in his topic and weaves them into the narrative.

I read his stuff because of his subject matter (he has written extensively about geology).  He also has a warm and engaging style, his readers all fall in love with him.  The subject matter is always interesting, often because the people he seeks out are so colorful.

In Rising From the Plains, about Wyoming geology, McPhee found David Love, a USGS geologist from Laramie.  Gone now, Dr. Love was a renowned field geologist, focusing on Wyoming.  His  family is an integral part of Wyoming history.  His father started and ran a sheep outfit on Muskrat Creek in the Gas Hills, one of the most remote places in the lower forty eight.

The way McPhee portrays the man, his career, and Wyoming history makes one of the best books I have ever reread.  And reread, and give away.  If you have even the slightest interest in geology, read the book.  Rising From the Plains is a standalone book, and is part of Annals of the Former World, a collection of long pieces about geology mostly along I-80, skipping over the midwestern mud.  North America has fascinating geology and Annals gives a good overview.

Another book I like is The Control of Nature.  If you want to modify what nature produces, you get politicians to adopt the policy, then hire engineers to figure out what to do, then design the solution.  Sometimes they are asked to do the impossible, like keeping the eroding San Gabriel mountains from filling the Los Angeles Basin or control the lower Mississippi River.  Ask an engineer if something can be done and their answer is always “Yes.”  They make their money building stuff.  They may need lots of money, all the better.  Many of their projects fail at some time.  Don’t move to Morgan City, Louisiana.

McPhee has a wide range of interests.  He takes his storytelling skills to The Swiss army, to Loch Ness, to the Illinois River, California earthquake country, Alaska, and my least favorite book about a fish called shad. I read the book, but I still don’t care about the clammy, bony, tasteless things.  Not biased, though.

He is well into his eighties, and now writes mostly about writing.  His method is a complex blend of research, note taking, and building a structure to hold the piece together.  He is a real structure freak.  I have an idea, think about it a bit, and rip something out, editing as I go.  Of course he is producing around 50,000 words.  I do 500 to a thousand.  I have a structure as well, as I also learned how make outlines.  I tend to adapt the Army way: tell them what you are going to tell them, tell them, and then tell them what you told them.  I like to introduce the subject, amplify it, then add my personal take.

Unlike McPhee, I tend to drift off topic into a rant or something mostly unrelated, but I like it.  “Oh look, a squirrel!”  Have I mentioned I have ADD?  I sometimes tend to bullshit; McPhee does not.  He has his extensive research and those wonderful New Yorker fact checkers.  I have my broken brain and Google.

Other McPhee assets are his sense of humor and his feel for dialect.  He is easy to read.

The Empty Quarter

Portion of Flat Tops Wilderness

Well, its not a quarter of Colorado, but it’s big and pretty empty.  North and west of the Colorado River and south and west of the Yampa River, the only towns of any size are Rifle, Silt, Newcastle, and Glenwood Springs along the Colorado; and Meeker in the middle.  Craig and Hayden are on the  Yampa.  I don’t count Rangely on the White River west of  Meeker as a real town.  It is just a bunch of oil field junk with a few forlorn people. I recently traveled through the heart of the region.

I am a Western Slope native, so I have been over the relatively well traveled roads.  I-70 (previously highways 6&24) and SH 13 from Rifle to Craig.  As a kid, I went fishing on Rifle Creek with my parents.  The

White River

White River drains the White River Plateau and The Flattops.  Piceance Creek drains the Piceance Basin and enters the White between Meeker and Rangely.

Meeker is a pretty town in the valley of the White River.  It’s a farm and ranch town with a sad past.  The Meeker Massacre in 1879 was the end of the Utes huge reservation  lands in Western Colorado. They were shipped to Eastern Utah.  The reason was the systematic U.S. Policy of cooping the Indians up or killing them.  There are grisly details, but it was just another example of the U.S. Policy of mistreating Native Americans that continues to this day.

Maybe you have heard of Trappers Lake.  It is an enclave surrounded by the Flattops Wilderness, a huge area of timberland dotted with many small lakes.  The only access is on horseback or backpacking.  It’s wet country, catching the storms as they leave the lower country to the west.  Hunters, fishermen, and tree huggers are the only travelers.

I never backpacked there, but two friends humped there way in years ago.  They talked about the beauty,  but mostly about the rain.  One of them had one of those convoluted open foam pads with no cover.  When the water came into the tent, he was lying on a sponge in a soaked down sleeping bag.  They left early.

West of SH 13, along the Grand Hogback,

Grand Hogback Between the Colorado Plateau and the Rocky Mountains

you are on the Colorado Plateau.  Go east, and you are in the Rocky Mountains, but not the Rockies you are used to.  The hogback is a remnant of the uplift that formed the Rockies.  The equivalent on the east side are those red rock hogbacks called the Flatirons, Red Rocks, and the Garden of the Gods.

No big mountains here, just a region of high plateaus.  The reason? Volcanism in the form of lava flows.  The White River Plateau was uplifted along with the rest of the Rockies, but instead of being eroded into those jagged peaks we are used to seeing, the basalt from the lava flows formed a resistant, flat caprock.  It’s not rugged mountains, but it has a beauty all it’s own.

Flat Tops Trail

The is a scenic byway between Meeker and Yampa I took for the first time,  At first, it is in the White River valley, then climbs up on the plateau and heads on east to Yampa.  The view to the south is where the Flattops drop down to the river.  It’s not a gentle slope.  The basalt caprock is underlain by the soft White River Formation.  The steep slope is subject to landslides, leaving large open, green slopes surrounded by timber.  It’s great summer range country for sheep and cattle.  It is also some of the prettiest country in our state.  I think I met two pickups on the road east of Buford, where the road turns off to Trappers Lake.  It’s gravel much of the way, but good gravel.

West of SH 13, on the edge of the Colorado Plateau, is the huge Piceance Basin.  It is a Structural basin next door to the Uinta Basin, mostly in Utah.  The basins are separated by the Douglas Arch, crossed by Douglas Pass, country where I spent a lot of time in my youth.  The arch is a western extension of the Laramide Orogeny, the mountain building period that formed the Rocky Mountains.  The edges of mountain ranges usually have foreland basins, areas of subsidence.   I am sitting over the Denver Basin.  The Piceance is the equivalent west of the mountains.  As the mountains rose, the fringes sank, creating huge synclines filled with the erosion products of the mountains.    The basins formed huge inland lakes which filled with sediment that became the Green River Formation, famous for its fossils and oil shale.

The Greater Piceance Basin

Because of all that rising and sinking, pockets form, trapping reservoirs of gas and oil.  The Piceance is one of the most productive natural gas fields in the country.  Rangely’s oil is also from the Piceance.  I drove the road running along Piceance Creek, which drains the basin to the west.  The area is all about natural gas, with some ranching along the creek.  There is a gas plant every few miles, and lots of truck traffic.  The basin used to be the home of a huge migratory deer herd, the deer summering in the Flattops and wintering in the basin.  The herd is still there, but all the drilling has greatly reduced the numbers.  Lots of elk there as well, their numbers increasing somewhat, probably due to less competition from deer.

The area is known as the Roan Plateau, which drops off to the Book Cliffs, an escarpment runnng from Palisade, CO to well past Greenriver UT.  It feels like home country to me, with memories of deer hunting in the Douglas pass area.  The scenery isn’t as dramatic as the red rock country to the south, but has its own beauty.  Plus, it isn’t as cluttered up with people.

Piceance, Uinta, Roan Plateau, Book Cliffs, all names for roughly the same country.  My list now includes going up into the basin proper, known mostly by Ute Indians, ranchers, oil field people, geologists, and aging wanderers.

Politicians, Geologists, Engineers, and Water

Mosul Dam

Mosul Dam

This story relies on a report by Dexter Filkins in the New Yorker magazine.  Mr. Filkins,  a Pulitzer Prize winner, is one of the best writers covering the Middle East. 

The Fertile Crescent, where civilization developed, exists because the Tigris and Euphrates rivers flow from mountains in Lebanon and Turkey to the Red Sea.  The terrain along and between the rivers is relatively flat making agriculture feasible.  The rivers flood every spring, bringing water and new sediment to the region.  Those conditions support a significant population, but annual fluctuations have always created problems for the people living there.  During drought years, crops fail and famines ensue.  Wet years bring flooding which displaces people and affects farming.   

These conditions prevail in every arid region dependent on irrigation for farming.  The Nile, the Fertile Crescent, and the Colorado river are prime examples.  In all three regions, the political system has chosen to attempt to regulate the annual fluctuations in the river.  The solution?  Dam the river, store water for dry years and catch excessive runoff in wet years.   

Glen Canyon Dam and Hoover Dam on the Colorado,  Aswan High dam on the Nile, and the Mosul dam on the Tigris are the attempts at a solution.  So, they decide on a dam upstream of the people, hire geologists to recommend a good location, and hire engineers to design and build the thing. 

This worked, to a degree, on the Colorado and the Nile.  Not so well on the Tigris.  The geology above Mosul with its 2.5 million people is a jumble of sedimentary rocks formed in conditions similar to today.  That means flat coastal areas are intermittently flooded by the sea or nearby rivers.  The water evaporates, leaving the minerals dissolved in the water.  That means salt, gypsum, limestone, and a mixture of soluble minerals and mud called marl.   

The layers are deposited in flat layers, but Middle East geology is like Middle East politics, a big jumble with forces pushing from several directions.  Above Mosul, it is quite a jumble, but sinkholes have always formed as water dissolves the soluble minerals, leaving voids that collapse.  It is called Karst topography.  Florida is a prime example, a limestone peninsula in a wet climate surrounded by water.  It rains, the water sinks in,  dissolves the limestone, and goes to the sea.  Florida is dissolving, the rock resembling a sponge.   

The rock above Mosul has both limestone and gypsum.  Gypsum is a sulfate mineral that is called plaster if pretty dry, wallboard if more hydrated, goo if very wet, and then dissolves.  The geologists said “No, no dam, it will fail”.  The politicians then talked to the engineers who said “it isn’t good to build here, but we can make it work”. 

Now, engineers make their money by designing and building stuff, whether asphalt, steel, concrete, earth, or software.  They seldom say “no, we can’t do that”. They would be breaking their rice bowl.  So they proposed grouting the rock below and under the dam with concrete to keep reservoir water from dissolving all that gypsum, which is much more soluble than limestone.  They built a grout curtain under the Dam site, but it wasn’t perfect.  There were gaps. They built the dam, and the increased pressure from the water in the reservoir started dissolving the gypsum at a higher rate.   

Sinkholes developed below the dam before it was built.  They put a big long room made of concrete called a gallery at the base of earthfill dam.  Where their tests show a void is developing, they drill a hole in the floor of the gallery.  Water shoots out, confirming there is a big hole down there.  They then use big pumps to pump grout into the hole until it stops, hoping the void is filled.  They then move to the next place. 

This has been going on since the dam was built in the 1980’s.  All that concrete pumped below the dam has not stopped the leakage, it just moves the leaks to another weak spot.  They will never be able to pump enough grout.  An Italian firm is there now, and they are a bit hopeful they can control the leaks.  The confounding variable is the political situation.  ISIS controlled the dam for a while, and grouting mostly halted, but void creation did not.  The battle lines of the war today are within earshot of the dam.  The Iraqi government is unstable, despite support from shifting coalitions.  The grouting program is at risk.  Maybe that doesn’t matter.  The dam will fail, we just don’t know when.   

Sixty feet of water will inundate Mosul.  Refugee camps with 1.2 million people will be affected.  In two days parts of Baghdad would be under sixteen feet of water. Downstream, an even wider area would be flooded with at least six inches of water.  As geologists always say, “It’s not a matter of if, but when.”  Death toll estimates range from 500,000 to 1.5 million souls.  The Iraqi economy will be destroyed.  Moral, listen to the geologists.

Climate Change

Florida Flooding

Florida Flooding

Here it is, the last day of November, and we still have some tomatoes from our garden.  We had the hard freeze a couple of weeks ago, but we brought quite a few in before it froze.  This fall has been the fall of pasta sauce and tomato soup.  Traditionally the first freeze is in September or early October.  Not this year.  Now, just because we have one warm fall doesn’t necessarily mean global warming, it is a matter of relatively long term trends.  That is happening, folks.   

Worldwide, it is about one degree Celsius and climbing.  The culprit is carbon.  We need carbon, our bodies are mostly water, but carbon hangs everything together.  Florida, for example, is mostly calcium carbonate, limestone.  The limestone formed even the peninsula was underwater with a climate encouraging the growth of untold billions of tiny organisms with calcium carbonate shells.  They die, and if whales don’t eat them, their shells sink to the sea floor.  Well, even if they do get eaten, the whale turds are calcareous.   

Porous Limestone

Porous Limestone

Millions of years and sea level change, and Florida emerges.  The cycle doesn’t end there.  It rains on Florida, and the slightly acidic rain starts dissolving the limestone, sending the carbonates back to the sea.  Enough of the limestone has dissolved to make the peninsula a honeycomb.  Sinkholes, underground rivers, high tides bringing ocean water inland and flooding streets in  Broward county.  The southern part of the state is headed back underwater.   The really big deal is that sea level is rising.   

I have given an example of the carbonate cycle, which is going on worldwide.  The other cycle going on is the water cycle.  Our planet is delicately balanced in temperature around the freezing point of water.  The water evaporates, and if it is cool enough, some of it falls as snow and accumulates, mostly in the polar regions.  At times the ice forming from all that snow has made it as far as Central Park in New York,  that is a lot of water tied up on land.  Sea level drops, and Florida emerges.  

Currently, the cycle is going the opposite direction.  The ice is melting, and the process seems to be accelerating.  Why?  Carbon.  Here in Denver, I see huge coal trains hauling coal south to be burned to run air conditioners in Texas.  The coal, carbon, is ripped from the ground where it has lain for millions of years, mostly dead plant life converted into coal.  It is burned, sending carbon into the atmosphere.  I drove here to the coffee shop burning gasoline, which comes from oil made deep underground from what once were living organisms.  The carbon goes into the air, the climate changes due to human activity.  We are in a new epoch, the Anthropocene.

Elemental carbon is fairly rare.  Diamonds, graphite.  Carbon likes to combine with other stuff to make, well, us and other living things.  That carbon gets sequestered in the earth, reducing the amount of carbon available to make new stuff.  There is a cyclical balance, dependent on worldwide temperature and, lately, us.  We burn carbon based fuels and the carbon dioxide goes into the atmosphere.   

The sun shines, warming everything up.  A lot of that heat gets radiated back into space, maintaining a balance favorable to life.  When that radiant heat meets a CO2 molecule, it warms the molecule.  More carbon, more heat in the atmosphere.  That’s greenhouse gas doing its thing.  The global climate warms up, making some regions wetter, some more dry.  We have gotten used to having a relatively stable climate, and we adapt to it in many ways.   

When the rain and snow fall changes, our adaptations stop working so well.  This is especially important in coastal regions, because all that polar ice starts melting and sea level rises.  Most of the population lives near the coast.  With the coasts moving inland, the people and all their stuff will have to move as well.  Battery Park at the southern tip of Manhattan gets flooded in big storms.  The subway tunnels flood, and people have trouble getting around.  The time is coming when they will be living in central New Jersey.  The horror. 

There are lots of people denying all this, saying it is just the normal weather cycle.  That is true, but it is a new normal, and is changing.   What to do? Stop putting so much carbon into the air and start putting it back into the earth.   That means big change in the way we do things, and those getting rich on the status quo don’t want their businesses upset.   Oil and coal, mostly, but they drive all of our economy.  So, they say it isn’t so, and let’s burn, burn, burn.   

What goes around comes around.  It is just a matter of time.

Breckenridge

Breckenridge

Breckenridge

Recently we spent a week in Breckenridge for a family celebration.  There were five of us in one big condo and two studios.  Late October is an interesting time in ski country.  The Quakies have shed their leaves and the only snow on the mountain is what they are making, or trying to make.  We thought the town would be pretty empty, but there crowds on the weekend, mostly from Denver. 

Summit County is one of my favorite mountain resort areas.  There are the old mining towns, Breckenridge, Dillon, and Frisco.  There are the three upstarts, Silverthorne , Copper Mountain, and Keystone, with old Montezuma a few miles up the Snake River.  The Blue River Valley is fairly large, and ringed by mountains.  The view is fine in any direction.  Our condo was just down from the lifts, so our view was east.  One night it snowed a couple of inches, so we got to see the transformation.   

Boreas Pass Road in Fall

Boreas Pass Road in Fall

We could see the Boreas Pass road as it winds up the mountain.  It is the old railroad grade for the Denver, South Park, and Pacific.  Several of those narrow gauge railroads had grand ambitions, looking to the ocean.  The South Park, as people called it, never got past Crested Butte.   

The part we are interested in is the branch that ran from Como in South Park over the Continental Divide to Breckenridge, up the Snake to Montezuma, and up Tenmile Creek to Kokomo.  Kokomo was a silver mining town and now is buried under tailings from Climax.  On the Blue and Snake rivers it was gold.  East of the Snake near Silverthorne are sedimentary rocks, the same as exposed at Dinosaur Ridge in Denver, the difference being a four thousand feet elevation difference.  No gold there.   

Gold Dredge, This One at Fairplay

Gold Dredge, This One at Fairplay

Most of the gold along the Blue River came from the Park Range, with Boreas and Hoosier Passes connecting Summit County with South Park.  Most of the gold from the Park Range came from placer mining, extracted from the gravels eroded from the mountains.  Placer mining started with gold pans, went to rockers and sluice boxes, and when mining became industrialized, big dredges excavated huge amounts of gravel, sluiced the finer dirt, sand, and gravel for the gold, and dumped the leftovers in the river.  The big rocks went out the back of the dredge, creating those huge boulder fields you see below Breckenridge and Fairplay.  Pristine mountain meadows were turned into barren rock fields.   

Above Breckenridge, some hydraulic mining went on.  Mountain streams were diverted into ditches and big canvas hoses with big nozzles. The mountainside was washed down into the sluice boxes for the gold, and everything else was dumped, creating more barren areas. 

Mining developed and scarred Colorado.  The new city of Denver produced much of the machinery making the scars.  The Tenmile range wasn’t heavily mineralized, so remained untouched for later ski area development and scars created by ski runs.  It was the Park Range holding the gold, much of it still there.  Where the Tenmile Range transitions into the Mosquito range, the mountains were again mineralized.  Gold, then silver at Leadville, Molybdenum at Climax (where I worked as a miner one summer), and lead, zinc, and copper most everywhere. 

Next, Leadville.

Arkose, Sand, and Loess

Geologists like to give common things fancy names.  Aeolian Deposition means wind-blown stuff from the mountains on the land.  Here in Eastern Colorado the South Platte and the Arkansas Rivers are in the process of hauling everything to the Mississippi Delta.  This is kind of a slow process, but a lot of stuff is already there.  Lots more is on the way.   

The material coming off the mountains is in three general categories: gravel, sand and dirt.  The stuff gets deposited, may get buried long enough to form rock (Castle Rock), but most of it sits around for a while, maybe millions of years, before it is washed into the streams and heads east. 

Castle Rock

Castle Rock

Along the base of the mountains are two kinds of deposits.  As the Rockies were rising, they eroded almost as fast.  Out mountains are mostly the roots of what was once there.  During wet periods, like when glaciers were melting, the chunks coming down were pretty angular.  The geologists call the deposits arkosic.  The Castle Rock Conglomerate is a good example.  At other times the erosion was so rapid that a mixture of angular rock and rounded river gravel were deposited together.  Rocky Flats between Golden and Boulder is an example.   

There are huge gravel deposits at the mouths of the many canyons emptying onto the flatter land where all the people live today.  Boulder didn’t get its name by accident.  I briefly worked for the telephone company in Boulder.  I was on a crew burying telephone cable in new subdivisions.  I ran a backhoe and a cable plow, a small bulldozer with a ripping tooth in back digging down about thirty inches and paying telephone cable out the back of the tooth (or plow).  In some places, we had to bring in a big D8 Caterpillar dozer with the power to rip through all the hard packed gravel so my little John Deere 450 dozer could do its job.  It’s sort of a Mini Cooper versus a Hummer. 

All those lakes you see near all the streams exiting the mountains are old gravel pits converted into water storage reservoirs.  You can find gravel in the South Platte River bottom in Nebraska that came out of the Rockies.  As the gravel is carried along, it erodes from angular pieces to progressively more rounded rocks, eventually becoming sand, clay, or just plain dirt. 

The flat country at the base of the Rockies is a patchwork of older rocks exposed by erosion, gravels and arkose near the mountains, then lots of sand, then dirt farther out.  A geologic map shows the patchwork.  Nature is relentless in its processes, but they are not uniform. 

Denver's Sand Creek

Denver’s Sand Creek

Eastern Colorado has several Sand Creeks, carrying the sand that blew out onto the flats to the South Platte or the Arkansas.  You can identify the sand deposits in Eastern Colorado because they are cow country, not suitable for farming.  My favorite Sand Creek runs from northern Aurora through some of the old Stapleton Airport property and on west to the Platte.  The Bluff Lake Nature Center can give you a good look at the sand and the loess.  Bluff lake itself is down along Sand Creek where you can play in the sand.  The trail leading down to the creek and lake drops down the bluff from the parking lot.  The bluff is loess.   

Bluff at Bluff Lake Nature Center. Loess

Bluff at Bluff Lake Nature Center. Loess

Under most of the eastern plains is the Pierre Shale or the Ogalla Formation.  The shale can be farmed, and the Ogalla holds all that rapidly diminishing irrigation water.  The surface is mostly stuff the wind blew in.  The dirt the wind carries is called loess, a German word.  The soil is fine, and in some places can be hundreds of feet thick.  That dust on your car after it sits out in Denver?  It will either be Mississippi mud or loess.  Well, even the loess will be mud someday, it is just being delayed for a while.

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