Rhyolite caldera complexes are the most explosive of Earth's volcanoes but often don't even look like volcanoes. They are usually so explosive when they erupt that they end up collapsing in on themselves rather than building any tall structure (George Walker has termed such structures inverse volcanoes).
A normal serum sodium level is between 135 and 145 milliequivalents per liter. As this value can vary from laboratory to laboratory, it is important to consult with your physician to get a proper assessment.
Sodium levels in the plasma are normally maintained at a level of between 135 to 145 mmol/L. The condition in which plasma level of sodium falls to below 135 mmol/L is called hyponatremia. Hyponatremia causes movement of excess water in the cells, causing them to swell.