A look back 250 million years ago when a massive volcanic eruption, (in what is now Siberia), spewed lava one mile thick over an area the size of Texas and caused intense climatic change that killed 95% of the life on the planet; paving the way for the next dominant species – the dinosaurs.

Africa's Sahara Desert is the size of the United States, making it the largest desert in the world. It's also the hottest place on the planet. But now an astonishing series of geological discoveries has revealed this searing wasteland hides a dramatically different past. Scientists have unearthed the fossils of whales, freshwater shells and even ancient human settlements. All clues to a story that would alter the course of human evolution and culminate in biggest climate change event of the last 10,000 years.

A look at past Ice Age eras that Earth has experienced throughout its existence; how the slightest changes in the planet's orbit and angle of rotation can bring them about; how long they can last, and when the Earth will endure another.

The Atacama desert is considered the driest place on Earth. Since human records of the area began, some places have never received rain. But the records don't stop there--the Atacama is also the oldest desert in the world, and recently it has been dated to an amazing 150 million years old. Other research shows that the surface of this desert is also incredibly ancient, with boulders lying there that have not moved for over 23 million years--more than 50 times longer than it's taken for our human species to evolve. The soil is so dry, it has been used as a test bed for the Mars rovers. And though the desert was once thought to be completely lifeless, strange bacteria discovered there have given scientists new hope that they might find life on the red planet. Atacama is also home to the largest copper mine in the world. Inspect the riddle of the Atacama and uncover how this extraordinarily dry landscape was created.

On August 27th, 1883 a series of blasts on the island of Krakatoa culminated in a colossal explosion that blew the island apart in one of the largest eruptions in recorded history. We explore the underground forces that led to this extraordinary explosion that killed over 36,000 people and the devastation that it caused. But this is not just history because Anak Krakatoa (the Son of Krakatoa) is growing bigger and bigger and will blow again

A look at the creation of the Mount St. Helens volcano in Washington state; its history of violent eruptions and the evidence another massive eruption could occur again in the near future.

The single longest linear feature on Earth--the "Ring of Fire" circles almost the entire Pacific. It is a ring of active volcanoes from White Island just north of New Zealand, through the South China seas, Japan, Kamchatka, the Aleutians, the Cascades and down through the Andes. Almost 25,000 miles long, it is one of the most awesome sights on Earth.

The Sierra Nevada, North America's highest mountain range, contains one of the most awe-inspiring geological features on the planet: Yosemite Valley. Walled by sheer 3,000-foot granite cliffs and made from one of the toughest rocks on earth, it is home to the mighty El Capitan and iconic Half Dome. Yet how this extraordinary valley formed has been the subject of controversy for over 100 years. Was it carved by gigantic glaciers or a cataclysmic rifting of the Earth?

Scientists seek clues to the formation of North America's Great Lakes, the largest expanse of fresh water on the planet; delving into an underground salt mine; investigating a fossilized coral reef; diving to the bottom of Lake Superior.

The creation of the Earth is explored. Included: a study of the planet's oldest rocks and meteorites to see what they reveal about the birth of the Earth and its continued existence after it was first formed.

It is one of the most man-made spaces on the planet, but everything in New York from the height of the skyscrapers to the way the subway was constructed to the position of the harbor is governed by the extraordinary forces that ultimately shaped this city. You can tell the geology of Manhattan at a glance by looking at the skyline. The skyscrapers of Midtown and Downtown are built on hard granite; the low-rise buildings in between are built on a soft, gravelly soil left over from the Ice Age. Learn how New Jersey and North Africa were neighbors 250 million years ago, how the rocks New York are built on are the remains of mountains that 450 million years ago were as tall as the Himalayas, and how Long Island is covered in rubble that remained as ice sheets retreated 10,000 years ago.

The San Andreas Fault runs roughly 800 miles through some of the most valuable real estate in the world. The southern section hasn't had a significant quake for over 300 years and is now primed and ready for another "big one." This new series takes a trip along the most famous fault line in the world and examine the geology that gives it its immense destructive power. It's an investigation given new urgency by recent warnings from 300 of America's leading scientists about the death and devastation that a major earthquake on the fault could unleash on Los Angeles.

It is the largest and most fearsome volcanic island on the planet. We'll scour the island for clues, to address the mystery of what powerful forces are ripping Iceland apart and lighting its fiery volcanoes. Here, lava rips huge tears in the ground and new islands are born from the waves. Yet despite the active volcanoes, Iceland historically has been covered in and carved by ice. Fire and ice collide, locked in a titanic battle, as glaciers explode and cataclysmic floods decimate the landscape. But Iceland's volcanoes have had ramifications far beyond the shores of Iceland, causing climatic chaos and devastation across the planet; a fate which may one day happen again.

Mt Vesuvius is the world's most dangerous volcano, and it threatens three million people. It was responsible for the most famous natural disaster of ancient history, the eruption that destroyed the Roman city of Pompeii. And its most recent blast was caught on film in 1944. Today Vesuvius is the most densely populated volcano in the world. Now recent scientific discoveries show that it is capable of an eruption larger than ever before thought possible and that hidden beneath Vesuvius there is a vast magma chamber of boiling hot rock, ready to come out.

The Marianas Trench is the deepest place on earth, deeper than Mt. Everest is high. The trench is where the ocean floor disappears into the center of the earth. The pressures at this depth are 17 times greater than what it takes to crush a nuclear submarine. Only two men have ever been down the Trench, fewer than have set foot on the moon. Follow the daring missions into the abyss and explore the extraordinary geology that has created this deep scar along the ocean floor

Tsunamis are one of the most terrifying forces of nature, destroying all in their path. The December 26th Tsunami is estimated to have released the energy of 23,000 Hiroshima-type atomic bombs. What are the enormous forces that generate these catastrophic waves deep on the ocean floor? With 50% of the world's population living within a mile of the sea, this episode looks at what could happen in the future. East coast cities from New York to Miami face the threat of a truly colossal wave that could be generated by the collapse of an active volcano off the coast of Africa.