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.
In adults, the. symptoms may develop with serum sodium levels of. 150 mmol/l, although a majority of symptomatic pa-. tients have the values that are greater than 160 mmol/l. Levels over 180 mmol/l are frequently lethal (13).