Rock Strata Relative Dating- Diaz

​La llave al pasado...

Edad relativa- "Esta roca esta más antigua esa roca"

- podemos usar la ley de superposición y fósiles índice para indicar edad relativa


Edad absoluta- "esta roca es 28 millón de años de antigua"

- Datación de carbono y otros métodos radiométricos

​Datación relativa- cuando le das la edad a una roca en comparación a otra.

ejemplo: roca A es más antigua que roca B.
Una edad exacta no se ha determinado.

Multiple Choice

Absolute Dating is...Edad absoluta es...

• Estimated

• Relative

• In comparison to other rocks- such as older or younger

• Exact age- such as 33 million years

Multiple Choice

Relative dating is...Edad relativa es...

• Estimated

• Absolute

• In comparison to other rocks- such as older or younger

• Exact age- such as 33 million years

​En Espanol, es La Ley de Superposición

Fill in the Blank

The scientific law that allows scientists to relative date rock strata, meaning they can tell which rock layers are older or younger, is called….

​Las capas de roca en lugares distintos se pueden "emparejar" con los mismos fossiles para determinar la misma edad usando fosiles índice

​Index fossils help scientists "match up" the ages of rock to determine they are the same age.

Multiple Choice

I am digging a rock in Colombia, then I go to Mexico and dig different rock strata. I find many of the same rocks layers and fossils in the same order, this tells me those samples are likely from the same time period.

• True

• False

​Fósiles índice- Algunos organismos solo vivieron un tiempo corto, antes de ser extintos. Si usas datación radiométrica, entonces sabes que la roca y fósiles cercanos tienen la misma edad que el fosil que se encontró.

​If they find one of these--->
Geologists know exactly
where in time they are digging.

​Si los cientificos
encuentran uno de
estos fosiles, saben
exactamente
donde estan excavando
en la escala geologica.

​Index
FOSILS

Open Ended

Index fossils must be widespread (in many places), abundant (many of them), and only lived during a short time. If I were digging rock strata, how would I know that a fossil only lived a short time? Si estuviera excavando estratos de roca, ¿cómo sabría que un fósil vivió poco tiempo?

Multiple Select

Index fossils are like a "bookmark". Why is this true? Por que los fosiles indice son como un marcador de libros?

• They "mark" where in the geological timescale nearby fossils and rocks are, just like "marking" a page in a book

• They refer to a specific time period, just like a bookmark is only referring to one specific page in the book

• They are a "shortcut" so that geologists do not have to radiometric date, just like you don't have to read the whole chapter to see where you left off