
July 2016 – TEXAS – Satellite
 radar images reveal ground movement of infamous sinkholes near Wink, 
Texas; suggest the two existing holes are expanding, and new ones are 
forming as nearby subsidence occurs at an alarming rate. Residents of 
Wink and neighboring Kermit have grown accustomed to the two giant 
sinkholes that sit between their small West Texas towns. But now radar 
images taken of the sinkholes by an orbiting space satellite reveal big 
changes may be on the horizon.
A new study by geophysicists at 
Southern Methodist University, Dallas, finds the massive sinkholes are 
unstable, with the ground around them subsiding, suggesting the holes 
could pose a bigger hazard sometime in the future. The two 
sinkholes—about a mile apart—appear to be expanding. Additionally, areas
 around the existing sinkholes are unstable, with large areas of 
subsidence detected via satellite radar remote sensing.
That leaves the possibility that new 
sinkholes, or one giant sinkhole, may form, said geophysicists and study
 co-authors Zhong Lu, professor, Shuler-Foscue Chair, and Jin-Woo Kim 
research scientist, in the Roy M. Huffington Department of Earth 
Sciences at SMU. “This area is heavily populated with oil and gas 
production equipment and installations, hazardous liquid pipelines, as 
well as two communities. The intrusion of freshwater to underground can 
dissolve the interbedded salt layers and accelerate the sinkhole 
collapse,” said Kim, who leads the SMU geophysical team reporting the 
findings. “A collapse could be catastrophic. Following our study, we are
 collecting more high-resolution satellite data over the sinkholes and 
neighboring regions to monitor further development and collapse.”
Lu and Kim reported the findings in the
 scientific journal Remote Sensing, in the article “Ongoing deformation 
of sinkholes in Wink, Texas, observed by time-series Sentinel-1A SAR 
Interferometry.” The research was supported by the U.S. Geological 
Survey Land Remote Sensing Program, the NASA Earth Surface & 
Interior Program, and the Shuler-Foscue Endowment at Southern Methodist 
University. The sinkholes were originally caused by the area’s prolific 
oil and gas extraction, which peaked from 1926 to 1964. Wink Sink No. 1,
 near the Hendricks oil well 10-A, opened in 1980. Wink Sink No. 2, near
 Gulf WS-8 supply well, opened 22 years later in 2002.
It appears the area’s unstable ground 
now is linked to changing groundwater levels and dissolving minerals, 
say the scientists. A deep-seated salt bed underlies the area, part of 
the massive oil-rich Permian Basin of West Texas and southeastern New 
Mexico. With the new data, the SMU geophysicists found a high 
correlation between groundwater level in the underlying Ogallala Aquifer
 and further sinking of the surface area during the summer months, 
influenced by successive roof failures in underlying cavities.
Satellite images and groundwater 
records indicate that when groundwater levels rise, the ground lifts. 
But the presence of that same groundwater then speeds the dissolving of 
the underground salt, which then causes the ground surface to subside.  –Physics
 
 
 
          
      
 
  
 
 
 
 
 
 
 
 
 
 
 
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