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 three main types of plate boundary: divergent, convergent and transform. Plates move away from one another at divergent boundaries. This happens at mid-ocean ridges. Plates move towards one another at convergent boundaries; one plate is forced below another in a process called subduction.Earthquakes and composite volcanoes are common at this type of boundary. Convergent boundaries are areas where plates move toward each other and collide. 2  These are also known as compressional or destructive boundaries. 3  Subduction zones occur where an oceanic plate meets a continental plate and is pushed underneath it. 4  Subduction zones are marked by oceanic trenches.