Scientists Explain Earth’s Missing Billion Years of Rock Layers
WHO:
Gizmodo - Janne Liebmann is a research fellow at Curtin University and the lead author of the study.
Gizmodo - Chris Kirkland is a study co-author and a geoscientist at Curtin University.
Live Science - Study co-author Nicolas Flament is a geoscientist at the University of Wollongong in Australia.
Live Science - Shanan Peters is a geologist at the University of Wisconsin–Madison and was not involved in the study.
Live Science - The research was published in *Nature*.
ZME Science - The article’s authors are Santosh Dhungana, a PhD candidate, and Nicolas Flament, an associate professor and ARC Future Fellow; both are affiliated with the Environmental Futures program in the School of Science at the University of Wollongong.
ZME Science - The article was republished from *The Conversation* under a Creative Commons license.
WHAT:
Gizmodo - Researchers analyzed more than 1,200 rocks spanning nearly 4 billion years and reported their findings in *Proceedings of the Royal Society A*.
Gizmodo - A lead-isotope signature appears consistently in rocks older than 2.76 to 2.63 billion years but is absent from younger rocks.
Gizmodo - About 70% of the rock samples came from Australia; the rest came from other parts of the world.
Gizmodo - The team studied feldspar and sulfide compounds, minerals that can preserve chemical traces of older crust.
Live Science - The Great Unconformity is a gap in Earth’s rock record: at the Grand Canyon, rocks formed about 1.7 billion years ago lie beneath sedimentary rocks laid down about 500 million years ago, leaving roughly 1.2 billion years unrecorded.
ZME Science - In some locations, sedimentary rock about 540 million years old or younger rests directly on crystalline basement rock as old as two billion years; the missing interval can represent up to a quarter of Earth’s history.
Live Science - The unconformity is also extensive in North America, the Baltic region and northern China. ZME Science also reports evidence in North America, northern China and northern Europe.
Live Science - The study’s model indicates mantle-driven uplift followed by subsidence can explain both erosion of older layers and the later preservation of new sediment layers.
ZME Science - The researchers report that Australia and South America experienced only two uplift-and-subsidence cycles from 900 million years ago, with little evidence of the Great Unconformity there.
WHERE:
Live Science - The Grand Canyon’s unconformity is visible between Cambrian Tapeats Sandstone and Proterozoic Brahma Schist.
ZME Science - The researchers modeled the continental blocks Laurentia, now much of North America; Baltica, parts of northern Europe; and North China.
WHY:
Gizmodo - The researchers said the disappearance of the lead-isotope signature suggests a major change in how Earth’s crust formed and transformed, marking a transition toward the modern tectonic system.
Live Science - Flament said mantle uplift created slopes that enabled glaciers and other erosive forces to carry sediments off continents.
ZME Science - The researchers say deep-Earth processes helped shape the environment in which complex life evolved; the Great Unconformity’s younger sedimentary layers appear alongside the Cambrian explosion, a major diversification of life.
HOW:
Live Science - The researchers modeled slow, heat-driven mantle circulation, which lifted the studied regions; later subsidence allowed sediments to accumulate on continents.
ZME Science - Using the Australian supercomputer Gadi, researchers modeled mantle movement over the past billion years. Their results showed uplift of Laurentia, Baltica and North China from around a billion years ago to 540 million years ago, followed by downward movement.
ZME Science - The article says ice sheets during the Snowball Earth period scraped uplifted continents for tens of millions of years, eroding rock as they moved downhill.
(UPDATED November 12, 2026 07:59 UTC)
Researchers link mantle movement to the Great Unconformity, a vast gap in Earth’s rock record. Their model shows uplift drove erosion, then sinking continents allowed younger sediments to accumulate. More than 1,200 rocks reveal a vanished chemical signature, signaling major changes in Earth’s crust.
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(UPDATED November 12, 2026 07:01 UTC)
A new study links mantle-driven uplift and sinking to Earth’s Great Unconformity, a vast gap in its rock record. Uplift exposed ancient rocks to erosion; later subsidence allowed younger sediments to accumulate above them. The geological shift coincided with the rise of complex life.