When it comes to natural disasters in oklahoma, the thing to worry about used to be tornadoes. Now it's earthquakes. However, these earthquakes are not natural but induced or manmade, and coincide with the fracking boom in the state. Native American lands are among those most affected, and now the Pawnee Nation is using its tribal sovereignty to challenge the fracking companies in court.

Number of induced earthquakes on the rise

The number of earthquakes occurring annually in the state has shot up from zero to over 600 in just about seven years.

From a starting point of zero to two earthquakes of magnitude 3 or higher each year, Oklahoma saw 20 in 2009, 109 in 2013, 579 in 2014, 903 in 2015, and 623 in 2016. Last year, Oklahoma had the dubious distinction of having more magnitude 3 earthquakes than California, averaging almost two a day.

Some of the worst quakes have affected Native American tribal lands, including the most serious one in September 2016. The 5.8 magnitude hit the town of Pawnee and and caused structural damage to tribal buildings and reservation property. The quake was felt in three states and Oklahoma governor Mary Fallin declared a state of emergency in Pawnee County.

The continuing earthquakes make it difficult to file insurance claims, with more damage occurring even before assessments have been made.

The earthquake also had a severe emotional fallout, leaving people scared and on edge. However, they're also determined to do something about it.

Sovereignty over tribal lands

The Pawnee Nation has filed a lawsuit against the fracking companies in the tribal court, alleging that they knowingly caused the earthquake and that their actions "constitute wanton or reckless disregard for public or private safety." Since the wells are on Indian tribal lands, the companies are subject to the jurisdiction of tribal courts in civil matters.

Induced or manmade earthquakes are caused by the injection of wastewater from the fracking process into the ground. This increases pressure on existing faults, making them more active.

The Pawnee Nation is represented by the law firm of Weitz & Luxenberg and has been joined by activist Erin Brockovich. Water quality has long been her signature issue, and she warns that wastewater disposal does invisible damage as well, affecting the quality of groundwater.

The lawsuit, according to Andrew Knife Chief, executive director of the Pawnee Nation, is not against fracking but against the unsafe practices used by the companies to reduce cleanup costs. The goal of the tribe and the lawsuit is to push for the responsible use of natural resources and the responsible disposal of waste.