The US Geological Survey has reported that Yellowstone National Park has experienced over one thousand earthquakes over the last two months. At present no one is certain whether the quakes are being caused by faultline activity, or the movement od volcanic magma within the cauldera. The quakes magnitudes have been in the 3.0 to 3.8 on the Richter Scale. It has been said if they strenthen to 4.0, and stronger, we may have to start worrying. Right now, all is within safe limits, but that can change in short order. Don't panic, but stay alert.