The hemoglobin test is often used to check for anemia, usually along with a hematocrit or as part of a complete blood count (CBC) . The test may be used to screen for, diagnose, or monitor a number of conditions and diseases that affect red blood cells (RBCs) and/or the amount of hemoglobin in blood.he hemoglobin test is often used to check for anemia, usually along with a hematocrit or as part of a complete blood count (CBC) . The test may be used to screen for, diagnose, or monitor a number of conditions and diseases that affect red blood cells (RBCs) and/or the amount of hemoglobin in blood.
Volcanoes form at hot spots in the Earth's crust, at convergent plate boundaries where subduction of oceanic crust is occurring, and at divergent plate boundaries where gaps i â¦ n the crust are being infilled with rising magma.
Why Volcanoes Occur. Magma is generated in the Earth's lithosphere, which is made up of the crust and upper mantle. (Description of Figure 1.). The roots of Mount St. Helen's are 110 to 330 kilometers (70 to 200 miles) below the Earth's surface.ount St. Helens is typical of more than 80 percent of the volcanoes that have formed on land. Known as subduction zone volcanoes, they occur along the edges of continents where one plate dives, or subducts, beneath a second plate. (fig. 2).