Category Archives: Geology

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 Upper Peninsula

Recently we visited Michigan.

Grand Marais and Lake Superior

Michigan is two realms, downstate and the U.P. as the locals call it, where we visited.  They call themselves yuppers, for U.P., the Upper Peninsula.  It’s the North Country, well north of Toronto, heavily wooded and bordered by Lake Michigan and Lake Superior.  My wife has an old friend who is from Grand Marais, a tiny town on the south shore of Lake Superior. It is 40 miles to the nearest supermarket or hospital.

Patty grew up there, and like most natives, had to leave to make a living.  After a career, she went back home.  I can understand why.  The U.P. is a magical place, and Grand Marais, with its 400 people, is one source of the magic.  The land, the lake, the history, and the yuppers combine to make a spot unlike any other.

Historically a fishing and logging town, it is now a retirement and tourist community.  The campground, with its tents and RV’s, has as many people in summer as the rest of town.  There is a K-12 school with 28 students, a few stores, restaurants, and motels; small houses with no fences, some new houses seeming out of place, and that’s about it.

The people talk funny.  Lots of Finns and Swedes settled there, and that Nordic accent prevails.  No one says yes, it’s yah.  The word the becomes da, and the vowels are round.  They are friendly, open, welcoming people with no pretensions.  I fell in love with them.

The land is second growth timber, still supporting a logging industry.  The trees are a mix of hardwoods and conifers.  The larger trees are about 24-30 inches in diameter.  Walk into the woods, and there are old stumps around four feet across.

The Old Coast Guard Station, now the National Lakeshore Ranger Station

 

 

 

We did some wandering at the Pictured Rocks National Lakeshore, just west of town.  The Park Headquarters is in the old Coast Guard Station in town.  The lakeshore has a waterfall, views of the lake and its lighthouses, the sandstone bluffs giving the park its name, and the log slide.  It is the first National Lakeshore.

 

Lake Superior Log Slide

The log slide was used to slide logs into the lake from sand dunes about 175 feet above the lake.  There is a trail with wooden steps leading down to the waterfall and the lakeshore.  We watched the young people frolicking in the water and running/sliding down the log slide.  The beach is rounded cobbles up to about softball size.  Just away from the beach is sand with people looking for agates that formed from water trickling through ancient basalt lava flows.

Another day we went blueberry picking in a logging clear cut.  Lots of blueberry plants were hiding in  west the bracken.  We kept an eye out for bears attracted to the blueberries. The berries went into pancakes and muffins.  Driving off the pavement is a bit dodgy due to the sand.  We had to back down one hill.

Another notable thing was the silence.  I live in the city, with a constant background of noise.  Grand Marais was quiet.  I am sure the town is even quieter in winter with three or four feet of snow on the ground on the rare day with no wind.

Pictured Rocks National Lakeshore

 

The logging and fishing history is important, but the shipwrecks are a thing of legend.  The south shore of Lake Superior is a lee shore.  A lee shore is when the shore is leeward (downwind) of a sailing vessel.  In the days of sail, Lake Superior schooners were often blown onto the south shore by the fierce north and westerly winds.  It is difficult to sail upwind in a big blow, and the lake is famous for its storms.

Lake Superior Schooner

You probably know Gordon Lightfoot’s “The Wreck of the Edmund Fitzgerald”.  Ships under power weren’t immune to the storms.  Standing on the shore of that immense lake, I could feel the draw of that big lake, and began to appreciate both the beauty and the danger.  Today, the shipping is well offshore.

I never felt I could fall in love with flat country, but I do love the U.P.

 

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.

Leadville

Leadville

Leadville

As part of our week in Breckenridge, we did a day trip to Leadville over Fremont Pass.  This country figures in my life.  My father grew up in Leadville, and I worked at the Climax Molybdenum mine one summer when in college.  Breckenridge is low country, around 9600 feet.  Leadville is over 10,000 feet in elevation, the highest incorporated city in the U.S. Climax is at the summit of Fremont Pass, 11,360 feet in elevation.  Some years, it doesn’t snow in July.   

Climax, Elevation 11,300 Feet

Climax, Elevation 11,300 Feet

Climax is at the foot of Bartlett Mountain, once one of the largest bodies of Molybdenum in the world.  Moly is used in alloying steel and as a lubricant.  Moly alloyed in steel makes it tougher, useful in high stress applications.  It’s first big use was in gun barrels during WWI.  Much of Bartlett Mountain is gone, hollowed out, crushed, had the metals removed, and the tailings dumped into a once beautiful glaciated valley.  Common with most mining operations, Climax has gone through several boom-bust cycles, and is currently just limping along.  Leadville is limping as well, still dependent on mining. 

I worked at the Storke level, 300 feet down the mountain from the original portal and mill.  I lived in a company hotel there. There was once a company town, but it went away as the milling operation took the land.  The store and the beer joint were still there in the mid-1960’s.    

I worked as a miner.  Drill, shoot, and muck.  That’s mining.  The drill was a jack leg, a pneumatic rock drill with a leg attached to be extended as the drill hole got deeper.  It was powered by compressed air, and had a water feed to keep dust down.  Drill holes in the face, load them with explosive, shoot, then remove the broken rock (muck).  I plan to go into the whole operation some time.  I did it for the money, and I can now say I was a miner. 

Leadville is down the pass.  What a place.  First gold, then a lot of silver, then bust as the silver market collapsed.  Mining has always gone on, from small independent operations to massive developments supporting a fairly large town.  My grandfather lived there for about twenty years as a railroader, a good Union job.  Born in 1903, my dad grew up there until 1918 when the railroad went broke and the family moved to Grand Junction.  Growing up, I heard lots of Leadville stories.  I will tell some more sometime.  If you go down the hill from the hotel on Harrison Avenue, the house at the bottom on the right is where my father grew up. 

Mining Hall of Fame

Mining Hall of Fame

When we visited, we drove around and I bored everyone with Leadville stories.  We ate at the Golden Burro, where I ate in the 1960’s, and went to the mining museum.  If you have any interest in mining, that’s the place.  Mostly, mining is taking metals and fuel from the earth and leaving a mess.  Leadville has lots of messes.  The worst ongoing mess is the water.  As it comes out of the mines it is highly acidic and loaded with toxic metals in solution.  It will have to be treated forever, at least in human terms.  Mining built Colorado, and we will always deal with the legacy.  Oh, what a mess we made.

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.

The Green River Formation

The World Famous Green River Formation, for oil shale, not beauty

The World Famous Green River Formation, for oil shale, not beauty

About fifty million years ago the Grand Canyon and the Colorado River did not exist.  The area was surrounded by the Wind River Mountains, the Uintah Mountains, the San Juans, the Uncompahgre Plateau, and the newly formed Rocky Mountains.  This huge area had no outlet to the sea.  The climate was similar to our current Gulf Coast, warm and moist.  During the six million years we are exploring, things changed.  Lakes formed and receded, land rose and subsided, and through all this the surrounding highlands were sending their sediment into the lakes.   

The Green River Formation is the result of all the sedimentation.  It is up to ten kilometers in depth, thinner at the margins.  At first the lakes were fresh water, but later became saline, leaving large deposits of carbonate rocks.  The trona deposits at Green River, Wyoming are some of the richest in the world.  The margins are sandstone and conglomerate interlaced with the fine silt that filled most of the basin.  The formation is rich in the fossils of the abundant life in the lakes.  They are world famous for their variety and abundance.   

There was an anoxic layer at the bottom that preserved the organisms settling there.  The lakes were abundant in blue-green algae.  The remains of the algae are the source of the oil shale deposits the region is known for.  The oil shale is there in millions of barrels, but it is expensive to extract the petroleum from the rock.  It may never be commercially viable, but the formation has been extensively studied as a result.  

Green River Formation Map

Green River Formation Map

Standing in my home town of Fruita looking north, the white cliffs behind the Book Cliffs are the Green River Formation.  The Roan Plateau is huge, but does not attract visitors like the red rock country to the south.  A huge exposure is the highlands west of I-70 from Rifle to DeBeque Canyon. 

My interest is from visiting ranchers and hunting in the Douglas Pass area in my youth.  Most of our visits were to ranches in the Green River Formation.  The elevations varied greatly.  The ranches were along West Salt Creek, but there were back country roads that went from sagebrush desert to piñon-juniper to oak brush shaly hillsides with sandstone rims to high country timber with world class mud.  In fact, the mud is world class everywhere in the region. 

Back before four wheel drive became common, there was a pile of rocks at the bottom of every big hill.  Load them in the back of your pickup, go where you planned, and unload them on the way home.  There is a network of canyons with side canyons branching off.  All of it is fine deer habitat.  My favorite places were at the head of a canyon with the wind in my face and a view of the LaSal Mountains and the Uncompahgre Plateau in the distance.  Flat, wooded country gives me the creeps. 

Access to a lot of the country is difficult.  Most of the land is BLM land, but the early ranchers homesteaded the choice land that had water.  The private land meant locked gates.  We knew some of the ranchers, family friends.  Hunting season was a big deal.  There were maybe a dozen or more people, hunting during the day and drinking and playing poker at night.  The big ranch house had a big kitchen with a wood burning stove along with the stove in the big main room.  There was a light plant in the shed next to the house.  It looked like no generator you see these days.  There were also lots of Coleman lanterns when the light plant failed.  Good times and lots of venison.  The unheated bunkhouse was upstairs. 

Douglas pass was up the main road, gravel in those days.  It isn’t that high by Colorado standards, but made up for it with the switchbacks up the head of the canyon to the summit up through that shale.  When the shale is wet, it moves.  The road trapped the runoff, wetting the soft shale, and most every spring one or more places slid.  The mountainside now is braided with old road cuts.  It wasn’t much of a main road in the 1950’s, but now there is so much oil and gas development that the road is a paved state highway that the highway department spends money on. 

The road crosses the desert above the Highline irrigation canal before it goes into the canyon.  It is on the Mancos shale, responsible for all that flat desert in Colorado and Utah that turns to grease when it is wet.  There was one hill the road went over then descended into the wash on the north side.  That meant the road was on a north facing slope for a distance.  That hill was named Coyote, because it could bite and gnaw on you if it was wet.  A bit farther north was a ten or twelve foot high rock on the side of the road, all by itself.  

The county employee maintaining the road in those days had his grader blade scrape on that rock every time he bladed the road.  It would leave a bump, so he would have to drag dirt over to level things out.  One day he got fed up and dug that rock up and moved it off the road.  It was probably a two day project, but he never had to fight that damn rock again. 

After I could drive, I ran around that desert quite a bit.  I learned how to drive a two wheel drive pickup in that greasy stuff from my father.  He was the telephone man in Fruita, responsible for maintaining the toll line as far as Cisco, Utah.  That meant navigating two ruts through the cheat grass and sagebrush.  He could put a two wheel drive pickup into places that were a challenge for a Jeep.  Rocks in the back, chains if needed, put it in second gear and putt along.  He seldom used the granny gear or used the gas pedal.  Those old Chevy sixes would just lug their way along.   

I am as guilty as any back country explorer for spending most of my time in the Rocky Mountains or the Utah red rock country, but the Mancos Shale and the Green River formation are calling me.  I just need to see if my tire chains are in good shape.  I think I will go over Douglas Pass, loop around and look the Piceance Basin over. From Rifle I will go down to Plateau Creek (my father and grandfather said platoo crick) and up to Collbran to look at the big slide.

Time

Time

Time

Time is relative.  It is all a matter of perspective.  It is said that realized beings like Jesus or the Buddha lived entirely in the moment, which connects them with the timelessness of being.  For mortals such as I, it is sometimes difficult to have a perspective greater than the next few hours.  Carol and I do a weekly plan, setting our schedule for that span of time.  For people in the corporate world, time usually means the bottom line for the quarter.  Children see summer vacation as lasting a long time; for us old people, it’s over in a flash. 

I seem to have several time perspectives.  In my spiritual life, I attempt to be in the moment and in the eternal.  In meditation, however, I find myself planning the next day or reviewing childhood events, not in some exalted state.  My everyday life tends to be day by day, checking the weekly plan if I remember to.  Often I can’t remember which evening I am supposed to cook. 

I have developed something of a longer perspective on life as I age.  I am shocked to realize that a lot of people were born in this century, which for me is a relatively short time.  Y2K wasn’t that long ago. I can remember Senator Joe McCarthy and the Army-McCarthy hearings when the country was experiencing  a right wing resurgence a lot like now.  That time ended, as will this one, probably in November.  I was in the Army when Kennedy was shot.  Obama is in year eight of his presidency; we have watched his daughters grow up.  As teenagers, I wonder if they think their dad is hopelessly clueless, even if he is The Man. 

Newspaper Rock, Utah

Newspaper Rock, Utah

My history professors talked about developing a historical perspective, to take a long view about human events.  To some degree I succeeded.  I can connect the pagan deities of Mesopotamia with elements of Islam, Judaism, and Christianity.  Four thousand year old Greek myths influence our current thinking.  Because of the American Civil War, I dislike grits, sweet ice tea, deep fried fish,  y’all, and that strange flag.  Most southerners are wonderful people, but I am not one of them.  But, I feel a connection with the people who illustrated their world on the sandstone canyon walls of Western Colorado and Utah. Parents with children born in 2009

2009So, where are we?  From “Do I have to go to the bathroom?”, to what’s to cook tonight, to the doctor’s appointment Thursday.  From there, it’s my lifetime and all that has gone on, even to those kids born in 2009, when my pickup was built (with a faulty airbag).from there it is the span of human history as recorded by symbols such as writing, the digital cloud, or rock paintings.  Then I  go to archeology and the origins of humankind. 

Next is yours and my favorite subject, geology and the universe.  Time changes, from hours to days to weeks, years, lifetimes, and all of human history, all mere blinks in the span of geologic time.  Four billion years ago our planet was a ball of very hot rock.  2.7 billion years ago what is now Denver was part of an island arc similar to Indonesia headed for a collision with Wyoming.  Lots of things crash in Wyoming. 

65 million years ago this place was a sea bottom, with shale accumulating that runs from South Dakota to central Utah.  Denver has gone from a hunk of hot rock to an island, a sea floor, a place being buried in the stuff washing out of the Rockies as the glaciers melted, to a place with a lot of people and their accumulated toxic waste and a lot of used plastic.   

The planet and the universe will go on, with humankind gone, mostly as a result of their own folly.  What does it all mean?  Maybe what is important is the time I took this morning to watch a big hawk fly over the DU campus looking for a little critter to eat.

 

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