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Project GEO

Geotechnical Engineering
Earth Science Outreach

Dr. Nick Hudyma
The University of North Florida
 
Bo Smith
Terry Parker High School

Fall 2004 Term Projects

Model Study of the Formation of Sinkholes
  Last Updated: December 15th


Our project, The Formation of Sinkholes, was a hands-on project to show how sinkholes are formed. To begin our project, we set up an experiment which consisted of six inches of sugar cubes as the foundation, one inch of clay with holes in it as the soil,and two inches of sand. In between the sugar cubes, we placed three plastic plates that acted as rock layers. One plate was placed two inches from the bottom of the set-up, the second plate was placed at three-fourths inches, and the last one was placed at five inches. Once the experimantal setup was complete, we set up a rainfall simulation system and watched how the rain had an impact on our sinkhole formation.
   While conducting our experiment, we learned that once the raindrops go through the sand it travels to the soil and down to the rock layers. Once the raindrops find an empty place where there are no rocks it just sits there. It makes a path for all of the other raindrops and over time all the raindrops come together and build up into a little puddle. Then other puddles start to build up at different areas in the rock layer. With all this water in the dirt, it slowly begins to erode and then finally it forms a sinkhole.
The conclusion of our project was that after a week the raindrops had caused the diagram to collapse forming a sinkhole. The process of the formation of the sinkhole was very slow until the raindrops started to travel through the clay and into the sugar cubes where they began to dissolve and erode.


Any questions? Please email Dr. Hudyma or  Mr. Smith

 "The T&V Sinkholes"
Vanessa Jackson  (left) & Tearra Walker (right)


Image Gallery of Our Project


 
web cam setup

the sand starts to seep through the sugar cubes

the sugar cubes are covered with sand and the experiment is ruined.


 

placing the sugar cubes as the foundation

measuring the length of sugar cubes

all of the sugar cubes are plcaed at 6 inches

placing one inch of clay on top of sugar cubes

pouring two inches of sand on top of clay-dirt/soil

picture of set-up on a computer screen


Trial #1
(Seccessful, because everything was set up right so nothing would seep through the sugar cubes.)
 

the process of the sinkhole formation started immediately

big chunk of clay breaks off

sinkhole formation still in progress

a completion of our model of the sinkhole formation



Trial #2
(Unsuccessful because the clay wasn't packed in tightly and the sand seeped through the sugar cubes.)

 
 

clay was not packed in tightly and the sand began to seep through 

sand wears the clay down and seeps through cracks causing a mess

sand ,sugar, and clay all dissolves together causing the project to be ruined