Evidence for change on Earth

Evidence for Change on Earth

By Mark Palmer

​Can You Explain It?
Scientists have collected many types of data over the years. These data indicate that most of the land on Earth was once a single land mass. This land mass split into the separate continents we see today.

Open Ended

Record everything you notice about the land on Earth.

Open Ended

What do you wonder about how the land on Earth changed? Brainstorm as many questions as you can.

Match

Match each term with its definition.

• the thin and solid outermost layer of earth above the mantle

• the solid, outer layer of earth that consists of the crust and the rigid upper part of the mantle

• the layer of rock between the earth's crust and core

• a rock that forms from compressed or cemented layers of sediment

crust

lithosphere

mantle

sedimentary rock

• crust

• lithosphere

• mantle

• sedimentary rock

​1. Superposition is a principle that states that younger rocks lie above older rocks if the layers have not been disturbed. In this image, the layer on top would be the youngest rock layer.

​2. Fossils are sometimes found in rock layers. A fossil is the trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock.

​3. An index fossil is a fossil that is used to establish the age of a rock layer. Index fossils are distinct, abundant, and widespread. The species that formed the fossil existed for only a short span of geologic time. Trilobites are index fossils.

​1. Plate tectonics is the theory that Earth’s outer layer is made up of large, moving pieces called tectonic plates. The theory explains how plates interact and how those interactions relate to processes such as earthquakes and mountain building.

2. A tectonic plate is a block of lithosphere that consists of the crust and the rigid, outermost part of the mantle. Earth's surface is divided into major tectonic plates, including the African plate.

Match

match

• a principle that states that younger rocks lie above older rocks if the layers have not been disturbed. In this image, the layer on top would be the youngest rock layer.

• are sometimes found in rock layers, and is  is the trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock.

• is used to establish the age of a rock layer and are distinct, abundant, and widespread. The species that formed it existed for only a short span of geologic time.

• the theory that Earth’s outer layer is made up of large, moving pieces. The theory explains how plates interact and how those interactions relate to processes such as earthquakes and mountain building.

• a block of lithosphere that consists of the crust and the rigid, outermost part of the mantle.

Superposition

Fossils

Index fossil

Plate tectonics

Tectonic plate

• Superposition

• Fossils

• Index fossil

• Plate tectonics

• Tectonic plate