TEPHRA AND PYROCLASTIC ROCKS. The rapid eruption of expanding gases results in the obliteration and fragmentation of magma and rock. The greater the explosivity, the greater the amount of fragmentation. Individual eruptive fragments are called pyroclasts (fire fragments).Tephra (Greek, for ash) is a generic term for any airborne pyroclastic accumulation.Whereas tephra is unconsolidated, a pyroclastic rock is produced from the consolidation of pyroclastic accumulations into a coherent rock type.he greater the explosivity, the greater the amount of fragmentation. Individual eruptive fragments are called pyroclasts (fire fragments). Tephra (Greek, for ash) is a generic term for any airborne pyroclastic accumulation.
Test the temperature of the milk with an instant-read thermometer once the milk has begun to steam and show small bubbles. Milk is considered to be scalded once it exceeds a temperature of 180 degrees F. Select a heat-proof measuring cup that is capable of holding at least twice as much milk as you wish to heat.
The bottom of the pot will get to a much higher temperature than the top and you need to constantly stir. Trust me, you donât want your milk to scorch! If you do scorch the bottom of the pan, the burnt milk will stink up the entire house and ruin all of the milk. Then your milk becomes dog/cat/pig/chicken etc. food. Heat, stir constantly, take the temperature and make sure that the temp remains at 161 for 16 seconds and cool down rapidly (see below). Double-boiler method (recommended): Far simpler than the previous method is to use a double boiler. This ensures that your milk will not scorch.