Category Archives: Denver Basin

The Urban Oil Field

Oil and Gas Wells in Part of Weld County

Weld County, Colorado is one of the richest agricultural counties in the nation.  It is also rich in oil and gas, leading to hundreds of wells extracting petroleum.  With all that money around, Northern Colorado is booming, with people moving and subdivisions being built on what was farmland.  The houses and wells are often neighbors, close neighbors.  As oil companies put profit ahead of proper well management, disasters ensue.  Colorado has lots of fires in the urban-wild land interface.  In Weld County it is the urban-oil field interface.

Colorado is home to 48,000 active wells and 52,000 abandoned wells.  All of them are potential  fire and explosion hazards, and can release methane into the atmosphere.  Think about that when your furnace comes on in the morning before you head out to your car.  We need renewal energy.

The Denver Basin is a huge geologic feature extending along the eastern front of the Rocky Mountains.  As the Rockies were uplifted, the Denver Basin subsided while filling with debris washing out of the mountains.  There is a 22,000 feet difference between the bottom of the Basin and the summits of the mountains.  That is a lot of gravel.

When there is a lot of structure in geologic formations, there is opportunity for oil and gas to migrate into the rocks.  The Denver Basin is one of the largest gas fields in the United States.  Oil and gas extraction started in 1901 in Boulder County.   Trillions of cubic feet of gas and millions of gallons of oil have come out of the ground since then.  Most of the production has come from sandstone or fractured shale.  The development of horizontal drilling and fracking has accelerated the process.  In Weld County, sites with as many as five wellheads and the installations to process the gas are next to residential areas.

Oil Fire Near Homes

The result is spectacular explosions and fires near where people live.  Local fire departments, once used to fighting grass and barn fires, have sprayed thousands of gallons of firefighting foam on the fires and spent days on the fire scenes.  Attempts to increase regulation of the industry mostly fail due to the political clout of the oil and gas industry.  The politics may change with the election of Democrats to most of the state offices.

Keep in mind the oil bonanza is a major source of Colorado’s economy and growth.  The move to renewables is also a source of revenue to the region, but there will be inevitable disruption during the transition.  The oil and gas industry seems to be focused on keeping the wells flowing, regardless of the environmental consequences.  They do not seem to be shifting into renewals themselves, which may be a death knell.  Market forces will probably prove to accelerate the shift to renewables.  They are much cheaper than dragging fossil fuels out of the ground and pouring tremendous amounts of carbon into the atmosphere.  The remains of dinosaurs and ancient swamps need to stay in the ground.

Notes on Climate Change

Everyone who thinks is aware of the impact climate change on our weather.  Drought in some places, more violent storms, and water coming out of manholes in South Florida.  Drought may be a cause of the instability in the Middle East.  People forced off the land move to the cities, always hotbeds of turmoil. The west coast of central America has also had a drought resulting in crop failures, with many coffee trees dying.  The people displaced move to the barrios in the cities.  California has had its cycle of wet years followed by drought, fires, and flooding when the rain returns.  The cycle is mostly intact, but extended drought followed by huge fires seems to intensify the cycle.  The rains, when they come, are stronger, with big debris flows devastating large areas.

We are in the anthropocene, a time of massive human impact on the earth.  Climate change is a result of dragging hydrocarbons out of the ground, burning them, and returning carbon dioxide once sequestered to the atmosphere.  Atmospheric CO2 traps heat, warming the oceans.  Warmer water holds less oxygen, meaning many sea creatures are killed.

Permian Temperatures

The Permian Extinction was about 252 million years ago.  A major cause was a huge increase in CO2 due to a number of factors, mainly extensive lava flows in Siberia releasing CO2.  Lots of sea life died, but the land got greener and wetter, again sequestering CO2 as coal and petroleum.  There are other factors to the extinction, but the result was 98% of sea life dying, with more than 70% of land life.  It took about 10 million years for life to recover.

We are not going to see a die-off of that magnitude anytime soon, but the climatological and geological records illustrate the risks.  The science is clear, and science offers the remedies, but taking action is a political matter.  Here is where an old adage comes in to play.  “Money Makes the World Go ‘Round.”  Lots of businesses are making money producing and burning hydrocarbons.  Those businesses strongly influence political decision making.  Our Current Leader is mainly motivated by money, so you do the math.

It is getting bad, folks.  It looks like it is going to get worse.  I Hope reason and sanity will prevail in time.

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?