Thyroid replacement hormones usually are well tolerated. Symptoms that occur during treatment are often due to toxic, elevated levels of thyroid hormones and resulting symptoms from hyperthyroidism.
Facts about the New Madrid Seismic Zone. The New Madrid Seismic Zone (NMSZ) is the most active seismic area in the United States east of the Rocky Mountains. The NMSZ is located in southeastern Missouri, northeastern Arkansas, western Tennessee, western Kentucky and southern Illinois.
Possible causes of the New Madrid earthquakes. Over the past 4,500 years, a number of major earthquakes of magnitude 7.0 to 8.0 occurred in the NMSZ. These events include clusters of large earthquakes that have been dated to 2350 bce, 900 ce, and 1450 ce.