Fault Lines

Roughly four billion years ago, during the Hadean and early Archean, Earth's crust was a patchwork of newly stabilized blocks whose tectonic behavior remains debated among geochemists. Recorded live at Goldschmidt 2026 in Montréal, this episode asks whether plate tectonics began as one clean global shift or emerged unevenly across different regions and times. Ola and Amara compare zircon evidence...

Amara opens with a cinematic tour of the 520-million-year-old Xiannüdong reef in Shaanxi, China, where hot Cambrian seas hosted nearly every major animal group — except one conspicuously absent group of filter-feeders. In this episode, we cover Scene-setting / cold open, Background / mystery setup, Core science / the discovery, and more.

Three hundred and nine million years ago, the land beneath modern Chicago was a swampy equatorial delta — oxygen at 35%, club mosses thirty meters tall, and dragonflies the size of hawks. The central question of this episode: did early four-legged vertebrates develop through amphibian-style metamorphosis, or did they hatch as miniature adults from the start? Ola and Amara examine the Pardo and Man...

Sixty-six million years ago, in the Late Cretaceous, foraminifera-filled oceans teemed beneath skies that had never seen a mass extinction — until a 10-kilometer asteroid ended that world in seconds. This episode of Fault Lines asks whether the Chicxulub impact was purely a catastrophe, or whether it also structured what came next. Ola and Amara examine a June 2026 study in Communications Earth an...

On June 15, 1991, the sky over Central Luzon turned white as Mount Pinatubo sent an ash column 40 kilometres into the stratosphere. The central question this episode tackles is whether the canonical 0.5 degrees Celsius of global cooling attributed to Pinatubo is actually reliable — and what is at stake if it is not. Ola and Amara trace the mechanism of stratospheric aerosol forcing from Pinatubo's...

Seven hundred and seventeen million years ago, the equator was buried under sheets of ice in what geologists call the Sturtian glaciation, a freeze that lasted 56 million years. This episode asks a single question: was Snowball Earth a static, locked prison, or something far more dynamic? Ola and Amara examine two competing answers from the Cryogenian period (approximately 717 to 660 million years...

Sixty-six million years ago, Earth was a greenhouse world with no polar ice, CO2 above 800 ppm, and palm trees growing in Alaska. This episode of Fault Lines asks why all that warmth slowly disappeared over the following 50 million years of the Cenozoic era. Ola and Amara examine a University of Southampton PNAS study finding that seawater calcium dropped by more than half across that period, walk...

On May 18, 1980, a magnitude-5.1 earthquake stripped the entire north face of Mount St. Helens in seconds, releasing the largest debris avalanche in recorded history. The episode asks whether the monitoring revolution that followed actually prepares us for the volcanic events capable of ending mass life on Earth. Ola and Amara move from the 4.2 cubic kilometers ejected at St. Helens up to the Sibe...

Two hundred and fifty-two million years ago, a biologically stable marine world built over fifty million years was erased in geological near-silence. This episode of Fault Lines examines the central question of the Permian-Triassic extinction: what actually killed 96% of marine species, and did anything that followed deserve to be called recovery? Ola and Amara walk through the Siberian Traps as t...