MARCELLUS SHALENatural Gas in Pennyslvania
Where is Marcellus Shale in PA? Marcellus Shale
The contour lines tell thickness of the shale. Pink = 50 ft Green = 100 ft Purple = 150 ft Red = 200 ft
What is Marcellus Shale?
Shale – Sedimentary rock made from mud (clay and silt)
Black from high organic content(plant and animal remains)
Organic matter is source of gas
What is Marcellus Shale? High organic content
means high gas potential. Greater thickness means
more gas potentially available.
Shale composition means very little connection between pore spaces that hold gas.
Fractures help gas flow within formation.
Why does it contain Natural Gas? When the shale was
deposited as a mud, it was full of tiny pieces of organic material.
The same heat and pressure that turned the mud into shale also ‘cooked’ the organic material, creating natural gas.
What is a Drill Rig?New Technology: Drilling HORIZONTALLY
How do they extract the Gas? http://www.youtube.com/watch?v=Iz
g7ZWyWvgA
Value of Gas Deposit Estimated amount of recoverable gas is
516 TCF. (Trillion cubic feet)
US consumption of gas in 2006 = 21 TCF
Marcellus shale could support US consumption for 1-3 yrs.
Pros and Cons of the Marcellus Shale
Pros Jobs in low-
economic regions. Improved local
economy A possible $15
billion in economic output and $2 billion in state tax revenue in a decade.
Cons Excess water
consumption Treatment of
wastewater Destruction of land Contaminated
ground water. Release of Radiation
Cost of Drilling Consumption of water
Vertical well = 1.2 million gallons (28,000 barrels) of water
VS. Horizontal well = 3.5 million
gallons (over 83,000 barrels) of water.
Environmental Concerns Hydraulic fracturing consists of pumping a fluid
and a propping material such as sand down the well under high pressure to create fractures in the gas-bearing rock.
slickwater = a low-viscosity water-based fluid used to fracture the rock to release the gas.
The slickwater fracs may include: friction reducers, biocides, surfactants and scale inhibitors.
Hydrochloric acid is also used as part of the fracturing process.
Question: Could this get into the local drinking water?
Environmental Concerns Radioactivity: The Marcellus is
considered to be a “highly radioactive” shale.
Engelder is quoted as saying that he thinks the radioactivity is “in such low concentrations that it does not bother anyone.”
Environmental Concerns Each well requires approximately 1,000 truck trips to
complete. Telescoping well casings must be surrounded by
concrete to prevent leakage into ground water and aquifers.
Each frack requires 4-8 million gallons of water, with about 40% of that coming back up as “flowback” – heavily contaminated hazardous waste.
This is stored onsite or piped to “evaporation pits” until moved to an underground injection well, treated and re-used or (vast majority) treated and discharged to surface water.
Economical Advantages Jobs in a low-
economic region. A possible $15
billion in economic output and $2 billion in state tax revenue in a decade.
The drilling activity will stimulate the PA economy, creating: additional income
earned from workers in the Marcellus industry
Income for those supporting it.
More income from royalties and taxes.