About Sinkholes
Sinkholes
can be quite devastating, and can swallow almost anything. Like the Sarisarinama sinkholes, they can also be
beautiful and relatively harmless. The difference between stunning and disastrous is a matter of location. 
This sinkhole was turned into a tourist attraction, where people can take a
swim and enjoy the view.
A sinkhole is a depression in the land’s surface. SEE VIDEO (How Sinkholes Work) This happens from erosion of rocks or soil caused by moving water below the land’s surface. Water flowing into a sinkhole can cause it to expand and become more active. As the rock beneath the land’s surface dissolves, underground caverns and conduits develop and the surface eventually collapses. Sinkhole flooding can occur because water enters a sinkhole more quickly than it can drain. Heavy rainfall can prolong the stabilization of a sinkhole, which takes an average of a day.
Sinkholes called blue holes
occur in the oceans and form when coral reefs and islands collapse to massive
depths. According to Sandy Samra, blue holes are often popular diving
spots. Sinkholes vary in size from 1 – 600 metres in
diameter and depth (The Most Enticing) and can form anywhere in the world. They develop
slowly and sometimes unexpectedly. When not verified as true sinkholes by professionals, they’re called subsidence incidents.
Sinkholes often happen in areas where the rock beneath the land’s surface is either: (Sandy Samra)
o Carbonate rock
o Limestone
o Salt beds
o
Gypsum
o
Dolomite
o Any rocks
that can naturally be dissolved by circulating ground water
Sinkholes can be triggered naturally
through drought or heavy rainfall, or
human induced from altering the
natural water drainage patterns with: (Sinkholes 101)
o Ground water pumping
o
Development
practices (ex.: manmade water diversion systems), heavy
increase in water flow Formation of a pond or body of water
o
Changing the
land for industrial or run off storage ponds
o
Extensive weight
of new material that threatens the underground supporting material
o
Construction
o
Blasting,
drilling, mining
o
Heavy ground
loading
o
Sewer, drain pipes or broken septic tanks that break
o
Improperly compacted soil or
buried trash after excavation work
o
Vehicle traffic
Humans
have also been using sinkholes as waste disposal sites which threaten the
cleanliness in our underground water resources.
Common Signs of Sinkhole Activity (cracks
that manifest themselves): Cracks in...(How Are
Sinkholes Formed)
o
Walls
o
Foundations
o
Patios
o
Driveways
o
Sticking windows or doors
(will buckle and become
uneven because of the land activity)
o
Leaning trees or fence
posts (a geological
change on the property)
o
Dying
vegetation
o
Polluted or muddied well water,
o
Formation of new ponds and trees
Sinkhole Repair
First off, the hole must be clearly marked and fenced off if
necessary, and either the city law enforcement or the property owner repairs
the land.
Do it Yourself (Sinkholes 101)
Use only native earth materials or concrete. Anything that
decomposes or release toxins that are put in the hole can affect underground
water supply. Small holes often only
require filling with clean sand or soil. Additional fill may be necessary over
time, but most holes eventually stabilize. Never throw anything into a sinkhole
that could possibly contaminate groundwater!
In some communities, local government agencies may assist in
evacuating the home, assessing damage and reporting the sinkhole. Local
Emergency Management Offices and Personnel from your local Water Management
District may also assist. An inspector that is a licensed professional
geologist and is trained to recognize sinkhole activity might be able to tell
if a sinkhole exists on a piece of property. It is not possible at this time to
predict when and where exactly a sinkhole will develop. (Sinkholes 101)
When You Need Help
Rembco’s Geotechnical
Contractors Incorporated, is only one of the companies that fixes sinkholes for
the city. They use specialized drilling equipment and grouting
techniques with as little disruption to the surface as possible. Injection
pipes, in a grid pattern, and a thick grout is injected to build a concrete
“cap” over the fragile rocks. This technique is known as cap grouting.
Case Studies
The
largest natural sinkhole in
the world is the Qattara Depression near Cairo, Egypt. It is filled
with sludge and quicksand. It measures about 80 kilometers long, 120 kilometers
and covers an area of about 7,000 square miles, which is about the size of Lake
Erie.
The
sinkhole near Berezniki, Russia, started in 1986,
apparently when a potash mine was flooded,
and hasn’t stopped growing since (What Is the Biggest
Sinkhole). It measures more than 200
meters deep, 80 meters long and 40 meters wide. The sinkhole will threaten the
rail lines coming from one of the world's biggest mines if it continuous to grow.
According to Sandy Samura, we’re not exactly sure why the hole keeps growing.
According to Jacob Silverman, Sarisarinama sinkholes were first
discovered in 1974 high up on flat-topped mountains. Venezuela’s sinkholes are
practically perfect circles. These sinkholes have unique plant and animal
species found nowhere else but in some Sarisarinama sinkholes.
Work Cited
Writing
Samra, Sandy. "What is a Sinkhole and How Does it Develop?" Ed. Rebecca Scudder. Bright Hub. Bright
Hub Inc., n.d. Web. 19 Jan. 2013. <http://www.brighthub.com/environment/
science-environmental/articles/80114.aspx>.
"Sinkholes 101." Save Our Suwannee, Inc. WordPress, n.d. Web. 19 Jan. 2013.
<http://www.saveoursuwannee.org/florida-hydrology-101/sinkholes-101/>.
Silverman, Jacob. "How Sinkholes Work." HowStuffWorks. HowStuffWorks, Inc, n.d. Web. 19 Jan. 2013.
<http://science.howstuffworks.com/nature/natural-disasters/sinkhole.htm>.
"The Most Enticing and Magnificent Sinkhole Ever!" Funniest Area. N.p., n.d. Web. 19 Jan. 2013.
<http://funniestarea.blogspot.ca/2012/05/most-enticing-and-magnificent-sinkhole.html>.
"How Are Sinkholes Formed?" Secure Foundation Systems Inc. Secure Foundation Systems, Inc., n.d.
Web. 19 Jan. 2013. <http://www.securefsi.com/sinkholeformation.asp>.
"What Is the Biggest Sinkhole in the World?" WiseGeek. Conjecture Corporation, n.d. Web. 19 Jan.
2013. <http://www.wisegeek.com/what-is-the-biggest-sinkhole-in-the-world.htm>.
"Video: Massive sinkhole swallows up Toronto road." The Globe and Mail. The Globe and Mail Inc.,
n.d. Web. 20 Jan. 2013. <http://www.theglobeandmail.com/news/news-video/
video-massive-sinkhole-swallows-up-toronto-road/article608738/>.
"Sinkhole - Repair and Remediation." Rembco The Stabilizing Force. Rembco Geotechnical Contractors
Incorporated., n.d. Web. 20 Jan. 2013. <http://www.rembco.com/sinkholes.html>.
Images
"The Most Enticing and Magnificent Sinkhole Ever!" Funniest Area. N.p., n.d. Web. 19 Jan. 2013.
<http://funniestarea.blogspot.ca/2012/05/most-enticing-and-magnificent-sinkhole.html>.
"'The Great Blue Hole' A large underwater sinkhole off the coast of Belize." The Truth Behind the
Scenes Disclosure. N.p., n.d. Web. 19 Jan. 2013. <http://ttbtsdisclose.wordpress.com/2010/07/
07/the-great-blue-hole-a-large-underwater-sinkhole-off-the-coast-of-belize/>.
"Sinkholes 101." Save Our Suwannee. Save Our Suwannee, Inc, n.d. Web. 19 Jan. 2013.
<http://www.saveoursuwannee.org/florida-hydrology-101/sinkholes-101/>.
"The Great Lakes." Visible Earth. Paul Przyborski, n.d. Web. 20 Jan. 2013.
<http://visibleearth.nasa.gov/view.php?id=68562>.
"Top 5 Sinkholes Disaster in The World with Pictures." ContinuityPlanTemplates. N.p., n.d. Web. 20
Jan. 2013. <http://www.continuityplantemplates.com/
top-5-sinkholes-disaster-world-pictures>.
Videos
"Sinkhole - Repair and Remediation." Rembco The Stabilizing Force. Rembco Geotechnical Contractors
Incorporated., n.d. Web. 20 Jan. 2013. <http://www.rembco.com/sinkholes.html>.
"Video: Massive sinkhole swallows up Toronto road." The Globe and Mail. The Globe and Mail Inc.,
n.d. Web. 20 Jan. 2013. <http://www.theglobeandmail.com/news/news-video/
video-massive-sinkhole-swallows-up-toronto-road/article608738/>.
Silverman, Jacob. "How Sinkholes Work." HowStuffWorks. HowStuffWorks, Inc, n.d. Web. 19 Jan. 2013.
<http://science.howstuffworks.com/nature/natural-disasters/sinkhole.htm>.
