Teacher Resources: Finding the Evidence
How do we know today that the Barringer Meteorite Crater was caused by a meteorite? Features of the rocks in and around the crater provide several crucial pieces of evidence for an impact origin.
Overturned Rock Layers
In normal stratification of sedimentary rock, materials are deposited horizontally over time, with the youngest layer on top. In the ejecta blanket of an impact crater, this stratigraphy is inverted – the youngest layers appear at the bottom, and the oldest layers appear at the top. Daniel Moreau Barringer and others described these overturned rock layers at Barringer Meteorite Crater.
Rocks in Shock
Extreme temperatures and pressures from a meteorite impact cause extensive heating, melting, and deformation. Deformation occurs under the high pressures experienced as a shockwave passes through the target rocks during an impact (known as shock metamorphism). Because they can only be formed under these special conditions, these target rocks are considered indicators of shock.
Discovery Activity: When Was Upside Down the Right Side Up?
One piece of evidence that Daniel Barringer used to support his impact theory was that the rocks on the crater rim and in the surrounding plain appeared to have been deposited in the opposite order of the underlying bedrock.
Student discovery activity exploring inverted rock layers at the Barringer Meteorite Crater
Educational Standards Met
National Science Education
Science as Inquiry
- A1 All students should develop abilities necessary to do scientific inquiry
- A2 Students understand the process of scientific inquiry
History and Nature of Science
- G1 Students should learn that science is a human endeavor
- G2 Students should develop an understanding about the nature of science
- G3 Students should develop an understanding about the history of science
2061 Benchmarks for Science Literacy
The Physical Setting - Processes that shape the Earth
- 4C/M2a Some changes in the Earth’s surface are abrupt while other changes happen very slowly
- 1B/M1b Scientific investigations usually involve the collection of relevant data, the use of logical reasoning, and the application of imagination in devising hypotheses and explanations to make sense of the collected data.
National Educational Technology Standards
Standard 3 - Research and Information Fluency
- Students apply digital tools to gather, evaluate and use information