8/12/2019 SGAS_What is Shale Gas and Why is It Important

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What is shale gas and why is it important?Last Updated: December 5, 2012

Shale gas refers to natural gas that is trapped within shale formations. Shales are fine-grainedsedimentary rocks that can be rich sources of petroleum and natural gas. Over the past decade,

the combination of horizontal drilling and hydraulic fracturing has allowed access to largevolumes of shale gas that were previously uneconomical to produce. he production of naturalgas from shale formations has re!uvenated the natural gas industry in the "nited States.

#oes the ".S. $ave %bundant Shale &as 'esources?

Of the natural gas consumed in the United States in 2011, about 95% was produced domestically thus, the supply ofnatural gas is not as dependent on foreign producers as is the supply of crude oil, and the deli!ery system is lesssub"ect to interruption# $he a!ailability of large uantities of shale gas should enable the United States to consume apredominantly domestic supply of gas for many years and produce more natural gas than it consumes#

$he U#S# &nergy 'nformation (dministration)s Annual Energy Outlook 2013 Early Release pro"ects U#S# natural gasproduction to increase from 2*#0 trillion cubic feet in 2011 to **#1 trillion cubic feet in 20+0, a ++% increase# (lmost allof this increase in domestic natural gas production is due to pro"ected growth in shale gas production, which grows from

#- trillion cubic feet in 2011 to 1.# trill ion cubic feet in 20+0#

(lthough the prospects for shale gas production are promising, there remains considerable uncertainty regarding thesi/e and economics of this resource# any shale formations, particularly the arcellus see map below , are so largethat only a limited portion of the entire formation has been e3tensi!ely production4tested# ost of the shale gas wellsha!e been drilled in the last few years, so there is considerable uncertainty regarding their long4term producti!ity#

(nother uncertainty is the future de!elopment of well drilling and completion technology that could substantially increasewell producti!ity and reduce production costs#

(n analysis in the Annual Energy Outlook 2012 released une 2012 indicates that the uncertainty in the si/e andeconomics of the domestic shale gas resources could ha!e a considerable impact on future domestic natural gasproduction and that 20*5 shale gas production could be between 9# trillion cubic feet and 20#5 trillion cubic feet# U#S#total natural gas production is pro"ected to range between 2.#1 trillion cubic feet and *+#1 trillion cubic feet# $heresource uncertainty cases will be updated and included when the full Annual Energy Outlook 2013 is released in thespring of 201*#

Where is Shale &as (ound?Shale gas is found in shale 6plays,6 which are shale formations containing significant accumulations of natural gas andwhich share similar geologic and geographic properties# ( decade of production has come from the 7arnett Shale playin $e3as# &3perience and information gained from de!eloping the 7arnett Shale ha!e impro!ed the efficiency of shale

http://www.eia.gov/forecasts/aeo/erhttp://www.eia.gov/forecasts/aeo/erhttp://www.eia.gov/forecasts/aeo/IF_all.cfm#uscrudehttp://www.eia.gov/forecasts/aeo/IF_all.cfm#uscrudehttp://www.eia.gov/forecasts/aeo/IF_all.cfm#uscrudehttp://www.eia.gov/forecasts/aeo/IF_all.cfm#uscrudehttp://www.eia.gov/energy_in_brief/images/charts/nat_gas_production_1990-2040-(large).jpghttp://www.eia.gov/forecasts/aeo/IF_all.cfm#uscrudehttp://www.eia.gov/forecasts/aeo/er

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gas de!elopment around the country# (nother important play is the arcellus Shale in the eastern United States#8eophysicists and geologists identify suitable well locations in areas with potential for economical gas production byusing surface and subsurface geology techni ues and seismic techni ues to generated maps of the subsurface# Seeanimated maps of production growth in the 7arnett Shale and arcellus Shale plays in Today in Energy articles )uly*+, + ** and ay + , + *+ #

:ydraulic fracturing commonly called 6frac;ing6 or 6fracing6 is a techni ue in which water, chemicals, and sand arepumped into the well to unloc; the hydrocarbons trapped in shale formations by opening crac;s fractures in the roc;and allowing natural gas to flow from the shale into the well#

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Source1 /ro/ublica, http122www.propublica.org2special2hydraulic-fracturing-national

What %re the 3nvironmental 4ssues %ssociated with Shale &as?>atural gas is cleaner4burning than coal or oil# $he combustion of natural gas emits significantly lower le!els of carbondio3ide =O 2 and sulfur dio3ide than does the combustion of coal or oil#