Shared Flashcard Set
Log in Sign up. How can we help? What is your email? Upgrade to remove ads. All matter is made up of tiny particles called what? When all the atoms in a particular type of matter are the same, the matter is a what? When elements break down, or decay, what do they release? Particles and some energy. When elements break down, or decay, they release particles and some energy in a process called what? During radioactive decay, the atoms of what break down to form atoms of another what?
Radioactive elements occur naturally in what type of rocks? Scientists measure the amount of radioactive decay in igneous rocks to determine the what of the rock? The rate of decay of each radioactive element has what type of rate? A constant rate- it never changes. The rate of decay is the elements what? Half-life can only be applied to what type of element? The half-life of a radioactive element is the time it takes for half of the radioactive atoms to what?
Geologists use radioactive dating to determine what kind of age for rocks? The half-life of what into argon is 1. When is potassium useful? In dating very old rocks. Which type of rock is best for radioactive dating half-life of what to what is 5, years old? When is carbon useful? Useful in dating materials from plants to animals that lived up to about 50, years old.
Radioactive dating works well for what type of rock? Which type of rock is best for radioactive dating dating does NOT work well in what type of rock? How do scientists date sedimentary rocks? Scientists use the dates of igneous intrusions and extrusions near the sedimentary rock layers to get an absolute date. What is relative age? What is absolute age?
The absolute age of a rock is the number of years since the rock formed. Geologists use what law to determine the relative age of what rock? The Law of Super Position; sedimentary. In what kind of sedimentary rock layer is the oldest layer at the bottom and each layer higher is younger? To determine relative age, geologists also study what? Intrusions and extrusions of igneous rock, faults, and gaps in the geologic record.
Lava that hardens on the surface is called what? Magma that hardens below the surface is called what? An extrusion is always what then the extrusion below it? An intrusion is always what then the extrusion below it? What is a fault? A fault is break in the Earth's crust. A fault is always what, than the rock it cuts through? Younger law of cross-cutting. A surface where new rock layers meet a much older rock surface beneath them is called a what? An uncomformity shows where some rock layers have been what?
Lost, due to erosion. Certain fossils called what, help geologists match rock layers? To be useful, index fossils must be what? Be widely distributed Represent an organism that existed only briefly. Why are index fossils useful? They tell the relative ages of the rock layers in which they occur.