Bedrock: Earth's Earliest History

Miniseries Episode 5: Asia is the largest continent, and has a lot of ancient rocks to share with the world. Today, we learn how to map a hidden continent using magnets, how copper forms in undersea castles, and how the Himalayas were born.

Miniseries Episode 4: South America has impressive geology, but most of its' ancient rocks are found in just once country. Today, we'll learn about ancient connections between Brazil and Africa, how Pangaea split apart, and how most iron mines got their start.

Miniseries Episode 3: Africa is a continent with many different nations and rocks. Today, we learn how most of Africa was fused together billions of years ago, and which pockets preserve the best evidence for ancient life (South Africa, Zimbabwe). Along the way, we'll meet the richest human in history, a giant knife made from magma, and a two-billion-year family reunion.

Thank you all for your patience these few months as I've started a new professor position in Grand Rapids, Michigan. Moving and preparing my first classes took all of my time and mental energy, but now I'm at a place where I can make episodes again! I'm excited to continue the story and I hope you are as well. More details are in the episode but in short: Oldest Rocks mini-series: 5 weekly episode...

Miniseries Episode 2: Australia is one of the top destinations for people who love the ancient Earth. Today, we take a brief tour around the three oldest regions in Australia: the Yilgarn Craton near Perth, the Pilbara Craton near Port Hedland, and the Gawler Craton near Adelaide. On the way, we'll meet the oldest minerals, the oldest fossils, and learn the connection between ancient bacteria and...

Miniseries Episode 1: The frozen continent holds many secrets, including some of the most ancient stones in the world, the Napier Complex 3.8 billion years old. Today we'll learn what things lurk in the ice, and a harrowing story of polar survival from an Australian geologist, Sir Douglas Mawson.

Our story will take a brief pause while I'm on summer vacation and fieldwork, including rocks more than three billion years old in Western Australia. But don't worry! In the meantime, there will be a seven-part miniseries on the oldest rocks of each continent. Tune in to find out which are closest to you, or use these as guides for a geology-themed vacation! After then, we'll return to the Hadean...

My guest today is Dr. Joti Rouillard, a research fellow at the University of Science and Technology in Hefei, China. Dr. Rouillard talks about his research on the earliest fossils on Earth, microscopic bacteria 3.5 billion years old. It turns out, identifying a fossil bacteria is extremely difficult since they resemble other tiny non-living objects. We also talk about working in the Australian Out...

When did life arise on planet Earth? Today, we look at the search for biological remains in the oldest minerals on Earth, the Jack Hills zircons of Western Australia, 4.4-4.0 billion years ago. We learn why carbon is an excellent building block for life, how to turn that carbon into diamonds and graphite, and why it's very hard to find conclusive fossils in very old rocks. Extra credit: Try to fin...

How do we know when the first oceans existed? Water leaves its' fingerprints over every surface of Earth, even in the oldest, toughest crystals. Today, we'll take an imaginary ride through the earliest oceans, examine how water slowly transforms everything it touches, and how these changes are recorded in the Jack Hills zircons, 4.4 billion years ago. Extra Credit: Make an underwater rock garden,...

How did water arrive on planet Earth? Today, we learn just how much water Earth has, and where it came from in the first place. We'll take a joyride around the early solar system, climb a snow-capped peak, and learn how Jupiter may have played a crucial role in making Earth's oceans. Extra credit: Drink some water, make a snowball, or watch the Kevin Costner classic Waterworld.

When did Earth's crust form? It's easy to take the ground beneath our feet for granted, but the story of our crust's origins is one of the most hotly debated topics in Earth history. Today, we'll learn how elements inside tiny crystals help solve this mystery. On the way, we'll meet two researchers who helped keep gold and scientists out of German hands in World War II. Extra credit: Look at table...

How is new crust made, and why isn't the Earth constantly expanding like a party balloon? To answer these questions, we'll track the life, death, and rebirth of Earth's surface. Stops along the way include the Mid-Atlantic Ridge, a fight to the death beneath New Zealand, and a stop for some Italian dessert. Extra credit: Experiment with your carpets at home, pushing them together and testing which...

The idea of plate tectonics is the cornerstone of modern geology. But it wasn't always that way, and it wasn't an easy idea to sell. Today, we'll meet two scientists who faced ridicule for proposing continental drift: a German climatologist and an American cartographer, the greatest of her generation. We'll also meet a lost expedition to Greenland, the Mid-Atlantic Ridge, and Jacques Cousteau. Ext...

What is the oldest thing on our planet? How old is it, and where was it found? Today, we tell the story of a worldwide, decades-long hunt for a single grain of sand. We'll journey to underground magma chambers, the sun-baked Australian Outback, and the lair of a giant shrimp. Extra credit: Let a handful of sand run through your fingers, or go pressure-wash something.

The Earth of 4.5 billion years ago was perhaps the most alien version of our world, thanks to a collision with a rogue planet. Days and nights were six times shorter, the newborn Moon was as close as a weather satellite, and everything was covered with a sea of magma. Today, we learn how the Moon transformed from a giant Eye of Sauron into our pale nighttime companion, with the help of a Canadian...

My guest today is Dr. Nadja Drabon, a new professor at Harvard University. Dr. Drabon talks about her new discoveries of zircon crystals from South Africa that are more than 4 billion years old, some of the oldest fragments of Earth. Together, we learn just how much we don't know about Earth's earliest days, and what her discoveries can teach us about our planet's ancient secrets. We also talk abo...

My guest today is Dr. Ella Holme, a postdoc at Yale University. Dr. Holme talks about her research on the mineral olivine as a potential antidote for climate change. Olivine can remove carbon dioxide from air and water, and further research into this mineral can help counteract increasing CO2 emissions. We also talk about how olivine is like the Hulk, and how Dr. Holme's path into geology started...

If you've ever wondered where the Moon came from, this the episode for you! To answer that question, we'll collect Moon rocks with Neil Armstrong, spin merry-go-rounds with Charles Darwin's son, and play planetary billiards. In the end, truth is stranger than fiction. Extra credit: Take some time for yourself and have a good long look at the moon.

Earth's first oceans were hundreds of times deeper than the Pacific and made of molten rock. Where did they come from, where did they go? What stuff was in them, how do we know? Today, let's dive in and see how these oceans turned into today's mantle. Extra credit: Drink a glass of ice water, watch The Core (2003), or see if you can find a garnet in your home or a museum.

Today, we'll learn how deep humans have traveled into the planet, and how we know what's even deeper down. We'll meet mineral oozes, coils of liquid iron, and a Danish woman from the 1930s who discovered the center of the Earth. Extra credit: Make a tin-can telephone, find an inductor in one of your electric appliances, or look for an aurora.

How did Earth grow from ant-size to, well… Earth-size? What perils did it face along the way? And how is the Earth's interior like a fine vinaigrette? Find out as we move forward in time from 4.6 to 4.5 billion years ago. Extra credit: try to freeze a mixture of oil and vinegar before they separate, find an iron meteorite at your local museum, or look for Ceres with a pair of binoculars.

Season 1 Premiere We finally start the tale of Earth’s history from the beginning, in the cold depths of outer space. The Sun is born and the first asteroids assemble. When these asteroids crash into Earth today, they provide time capsules from the beginning of the solar system. Extra credit: look for the Orion Nebula in the night sky, or go meteorite hunting with a friend.

Our introductory trilogy on deep time ends by tackling an important question: How do we know how old the Earth is?

How can rocks tell us the stories of ancient Earth- stories of magma, water, and life? To answer that question, we look at a few common rock types and examine how they formed.