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Mining & Resources · Recorded milestone

Reflection seismology

Recorded year1921

Sound waves bounced off rock layers reveal where oil lies.

Explore this milestone on the interactive map

Built on

Gusher-era oil extractionRecorded · 1901enables
Triode amplifierRecorded · 1906requires

Led to

Shale fracking boomRecorded · 2005enables
Moon's interior mappedForecast · ~2040enables
Real-time map of Earth's interiorForecast · ~2045enables

Sources & evidence

Additional source

Dataset updated 2026-10-18. This individual record has not been separately re-reviewed.