Karst and Land subsidence

Summary of the paper

The paper is about the research activity carried in the Holbrook basin in Arizona which has evaporate-karst depressions. The data obtained by the Arizona Department of Water Resources in the region is to be used for detailed evaluation of the deformation pattern in Holbrook basin to provide useful information that will help in strategizing on how to prepare to monitor the possible future subsidence that relates to the potash mining activities that take place around Petrified National Park (Conway & Cook, 2013). The paper provides background information on The Holbrook salt basin and that the main components found in the region id halite but there are also few amounts of anhydrite, sylvite, and gypsum. The area around Petrified Forest National Park has a significant amount of potash hence attractive resource for mining companies and investors (Conway & Cook, 2013). The paper also highlights the geological setting of the Holbrook basin to differentiate the salty body from the anticline. It also avails information on how the researchers used InSAR to monitor the land subsidence in the Holbrook basin. The results obtained, therefore, give the foundation for a withheld conclusion on the subsidence that might occur due to the mining of potash.

Main ideas in the research  

The research aims to determine the possibility for future subsidence in the Holbrook basin as a result of mining potash in the future thus collect relevant data to provide useful information for decision making. The research began by identifying the region of study and Holbrook basin was the most appropriate area since it hosts the Petrified Forest National Park and it is possible that mining activities could contribute to subsidence as they exert a lot of pressure on the ground (Conway & Cook, 2013). The researchers used InSAR to monitor land subsidence to provide information that is not only useful for them but also to other researchers in different states and county as well as the learning institutions. The available information helps them to develop different models for planning and designing projects to provide solutions to prevent land subsidence (Conway & Cook, 2013). Despite the sensors in the InSAR analysis using different wavelengths, the researchers managed to process them by using the same interferometric methodology. The use of interferometry was since the InSAR data set cannot process the c-band and L-band as it has different sensors.

The researchers concluded that they would continue to monitor the land subsidence rate even though it has not taken place recently. The researchers will continue to collect field observations, use photos as well as use the eastern area that has subsidized to act as a benchmark to monitor the land subsidence in Holbrook basin (Conway & Cook, 2013). The use of GPS to collect these data will provide supplementary data to the InSAR data to understand the land subsidence rate. The researchers have withheld the results from the research thus cannot make conclusions. They intend to visit the eastern region to obtain data and compare them, therefore, come with a satisfactory conclusion. This research is essential to the author as it provides detailed information for understanding the modern subsidence rate since evaporite-karst features in the Holbrook basin do not subside in recent years.
Thoughts

The InSAR results from the measurement that took place in eastern and western for four years show that the regions have land subsidence of 26 cm and 5 cm respectively (Conway & Cook, 2013). The figure may be an accurate representation of the existing land subsidence since the metamorphic processes result in increased pressure on the earth’s surface that causes the ground surface to shift downwards. Land subsidence can occur as a result of natural forces like earthquakes but also as a result of human activities like mining and the removal of natural gas. Therefore, it is possible that future mining in The Petrified Forest National Park will cause an increased rate of land subsidence in the Holbrook Basin.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reference

Conway, B. D., & Cook, J. P. (2013). Monitoring evaporite karst activity and land subsidence in the Holbrook Basin, Arizona using interferometric synthetic aperture radar (InSAR).