1 Brazil nuts contain high levels of minerals such as selenium, magnesium, copper, manganese, potassium, calcium, iron, phosphorus, and zinc. 2  Magnesium is a key nutrient in a whole host of biological processes. Dark, leafy greens are rich sources of minerals, but spinach in particular contains an abundance of magnesium, calcium, potassium, manganese, and zinc.
There are three kinds of plate tectonic boundaries: divergent, convergent, and transform plate boundaries. This image shows the three main types of plate boundaries: divergent, convergent, and transform. Image courtesy of the U.S. Geological Survey.
There are basically three different types of plate boundaries (divergent, convergent, transform), and a fourth type (boundary zones) is sometimes designated when it is difficult to define a clear boundary: 1  Divergent boundaries -- where new crust is generated as the plates pull away from each other.