How the story of the dinosaurs’ demise was uncovered.

Geologists have long used fossils to help identify parts of the rock record from around the world. From the distribution of fossils and other geological data, rocks and sediments reveal the history of the world. The story we narrated took place 65 million years ago, and is part of the alternative-history to the SF trilogy know as The Daimones Trilogy.

From Nautilus issue 32: The Day the Mesozoic Died 65 million years ago.

The K-T Boundary

From the distribution of fossils and other geological data, the K-T Boundary separates precisely, in sediments world wide, the Cretaceous and Tertiary periods. The names of these and other geological time periods come from some of the features that mark particular times.

The history of life is divided into three eras—the Paleozoic (“ancient life,” the first animals), the Mesozoic (“middle life,” the age of dinosaurs), and the Cenozoic (“recent life,” the age of mammals). The Cretaceous period forms the last third of the Mesozoic era. The Tertiary period begins sharply at the end of the Cretaceous 65 million years ago, and it is the time when the dinosaurs disappeared.

Throughout the limestone deposits, geologists find fossilized shells of tiny creatures, called foraminifera or “forams”, a group of single-celled protists that can only be seen with a magnifying lens, and that thrived in the primeval oceans.

But in one centimeter of clay that separated two limestone layers at sharp, abrupt dividing line between Cretaceous and Tertiary, geologists find no fossils at all. Furthermore, in the older Cretacean layer below the clay, the forams are more diverse and much larger than in the younger layer above the clay (the Tertiary layer). Everywhere in the world, geologists find that thin layer of clay and the same difference between the forams below and above it. Around the world, that boundary is always right where the dramatic reduction in foram diversity size occurred. The rocks below are Cretaceous and the rocks above are Tertiary, and the thin layer of clay is in the gap between (The K-T Boundary).

Luis Alvarez, a Ph.D. in physics in 1936 from the University of Chicago, and who worked at the University of California, Berkeley under Ernest Lawrence. Luis, an expert on radioactivity and decay, and an analysis of K-T Boundary samples revealed the unexpected, the boundary has about 30 times more than the normal level of iridium deposit, and than the level found in other layers of the rock bed. Why would that thin layer have so much iridium?

The research around the world showed samples of the K-T Boundary with iridium levels up to 160 times background levels. Something major had happened in the world at a particular time in history and the research confirmed that the phenomenon was global. Something very unusual, and very bad, had happened at the K-T boundary. The forams, the iridium, the dinosaurs were all signs—but of what?

It Came From Outer Space

Alvarez’s concluded right away that the iridium must have been of extraterrestrial origin. They thought of a supernova, the explosion of a star that could shower earth with its elemental guts. The idea had been kicked around before in paleontological and astrophysics circles. An astronomy colleague at Berkeley, Chris McKee, suggested that an Asteroid could have hit the earth.

A large amount of dust from a large impact could turn day into night for a few years, cooling the planet and shutting down photosynthesis. If so, how big an asteroid would it have been? From the iridium measurements in the clay, the concentration of iridium in so-called chondritic meteorites and the surface area of the Earth, Luis calculated the mass of the asteroid to be about 300 billion metric tons. He then used various methods to infer that the asteroid had a diameter of 10 ± 4 kilometers (km).

Such an asteroid would enter the atmosphere traveling at about 25 km per second—over 50,000 miles per hour. It would punch a hole in the atmosphere 10 km across and hit the planet with the energy of 108 megatons of TNT. (The largest atomic bomb ever exploded released the equivalent of about one megaton—the asteroid was 100 million times more powerful.)

Hell on Earth

The asteroid crossed the atmosphere in about one second, heating the air in front of it to several times the temperature of the sun. On impact, the asteroid vaporized, an enormous fireball erupted out into space, and rock particles were launched as far as halfway to the moon. Huge shock waves passed through the bedrock, then curved back up to the surface and shot melted blobs and bedrock out to the edge of the atmosphere and beyond. A second fireball erupted from the pressure on the shocked limestone bedrock. For a radius of a few hundred kilometers or more from ground zero, life was annihilated. Further away, matter ejected into space fell back to earth at high speeds—like trillions of meteors—heated up on re-entry, heating the air and igniting fires. Tsunamis, landslides, and earthquakes further ripped apart landscapes nearer to the impact.

Elsewhere in the world, death came a bit more slowly.

The debris and soot in the atmosphere blocked out the sun, and the darkness may have lasted for months. This shut down photosynthesis and halted food chains at their base. Analysis of plant fossils and pollen grains indicate that half or more plant species disappeared in some locations. Animals at successively higher levels of the food chain succumbed. The K-T boundary marks more than the end of the dinosaurs, it is also the end of belemnites, ammonites, and marine reptiles. Paleontologists estimate that more than half of all the planet’s species went extinct. On land, nothing larger than 25 kilograms in body size survived.

It was the end of the Mesozoic world, and the beginning of the history of humans in Daimones:

“The loss of Tiamat, and the lives which were also lost, constitute what we call the First Loss. This event took place around 65 million years in the past of your time. Your race caused that loss and all subsequent events.”

Daimones (The Daimones Trilogy Book 1)

Massimo Marino is a scientist envisioning Science Fiction. He spent years at CERN and The Lawrence Berkeley Lab followed by lead positions with Apple, Inc. and the World Economic Forum. He is also co-founder of “Squares on Blue”, a Big Data Analytics service company, and of BookGarage, a publishing service brokerage company.
Massimo currently lives in France and crosses the border with Switzerland multiple times daily, although he is no smuggler. #SFWApro

As a scientist writing Science fiction, he went from smashing particles at accelerators at SLAC and CERN to smashing words on a computer screen. He is is now an author with Booktrope Publishing,  LCC, and Active Member of SFWA – Science Fiction & Fantasy Writers of America.

He’s the author of multi-awarded Daimones Trilogy. The 1st volume, Daimones (The Daimones Trilogy Book 1), published by Booktrope is available since August 2015.

His novels have received the Seal of Excellency from both AwesomeIndies.net and IndiePENdents.org

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