Earth endured over one million years of rain in the Carnian Pluvial Event, which occurred about 232 million years ago, marked a dramatic turn in Earth's climate history. In an extraordinary shift, the planet transitioned from arid conditions to a prolonged phase of intense rainfall that lasted between one and two million years.

This significant event was initially identified through the examination of peculiar sediment layers in ancient rocks during the late 20th century, and has since captivated the scientific community.

The story began to unfold in the 1970s and 80s when geologists stumbled upon unusual sediment layers embedded within ancient rocks. In the Eastern Alps, researchers found evidence of siliciclastic sedimentation - a deposit typically associated with water - within carbonate rocks. Similarly, in the UK, geologist and forensic scientist Alastair Ruffell investigated a layer of gray rock deposited within the region’s characteristic red stone.

The evidence, found in diverse geographical locations from the Eastern Alps to the UK, points towards a world that was dominated by wet conditions, fundamentally altering the course of life on Earth.

The findings indicated a sudden and prolonged increase in precipitation that coincided with the dawn of the age of the dinosaurs - a time when these prehistoric giants began to diversify and flourish. This correlation hinted at the possibility that the wet conditions could have been a catalyst for the evolutionary success of dinosaurs and other terrestrial fauna, marking a pivotal moment in Earth's biological history.

Oldest Crystals In The World Reveal Earth Had Rain And Oceans 4 Billion Years Ago   IFL Science - June 4, 2024

Scientists develop 'X-ray vision' technique to see inside crystals   PhysOrg - June 4, 2024

A team of New York University researchers has created a new way to visualize crystals by peering inside their structures, akin to having X-ray vision. Their new technique which they aptly named "Crystal Clear" - combines the use of transparent particles and microscopes with lasers that allow scientists to see each unit that makes up the crystal and to create dynamic three-dimensional models. Evidence of Earth's First Rains Found Trapped Within Primordial Crystals   Science Alert - June 4, 2024

New research finds Earth's surface was first sprinkled with fresh water some 4 billion years ago, a whole 500 million years earlier than previously thought. A team of researchers used isotopes of oxygen trapped in ancient minerals to determine when the first signs of fresh water may have dampened the skin of our newborn planet.

The Jack Hills in Western Australia hold the oldest surviving material from the Earth's crust. For 4.4 billion years, the primordial minerals remained relatively unchanged by heat and pressure.

The dry, red, dusty landscape doesn't get much water these days, but scientists found evidence of the Earth's oldest rains trapped inside the rock's Hadean zircon crystals, and it's a big change to our understanding of the planet's hydrological history.

By examining the age and oxygen isotopes in tiny crystals of the mineral zircon, they found unusually light isotopic signatures as far back as four billion years ago.

The theory suggests that not long after the planet's sea of molten rock had congealed into a crust, Earth was cool enough to host liquid water, oceans, and a hydrosphere.

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