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.
When it reaches the surface, a volcano is formed. The magma flows out as lava, sometimes explosively. The majority of the world's volcanoes are associated with subduction zones. Since subduction zones represent plate margins, volcanoes tent to occur in lines, like the Cascade Range volcanoes or those on the Aleutian Peninsula. Once in a great while, a new volcano will form. This usually happens when an active underwater volcano produces enough lava to break the surface, such as Surtsey in Iceland in 1963.