Down to Earth Extra February 2025

The February 2025 edition of Down to Earth Extra has been published. You can download it HERE or you can read it below.

 Fish Vomit Fossilised

A correspondent sent me THIS LINK, for which I thank him. It concerns the find by an amateur fossil hunter of what turned out to be fish vomit. It consist of all the indigestible bits of what some fish had eaten. You can see bits of crinoid.

It comes from Stevns Klint which has some renown as a place where the contact between the Cretaceous and Paleogene can be seen, with its iridium enriched layer.

The specimen comes from the Cretaceous and helps us envisage life beneath the waves at that time.

The Fabulous Triassic 

A correspondent has brought THIS ARTICLE to my attention. It is from the Christmas edition of The Economist. You may have to go through some hoops to read it but you should get in without much difficulty.

And it is worth reading as it gives an overview of the Triassic AND it quotes Mike Benton!

The articles contention is that, although often overlooked, it is the period that led to the world as we know it. And it is fun to read!

 Why the Earth is Not Like Venus

At first glance the Earth and Venus should be similar and have geology with more resemblances than differences. A closer look tells us that it is a very different place.

The longest any lander has survived on Venus is 2 hours. We have been on Earth for rather longer. The surface temperature is about 465⁰C, the atmosphere is mostly carbon dioxide and there is virtually no oxygen and water.

Orbiters have used radar to look at the surface and conclude that it is mostly wrinkled plains of lava. There are lots of volcanoes and some are very large.

THIS ARTICLE will tell you all you need to know about the place; and comes to the conclusion that the crucial difference with the Earth is the lack of a magnetic field of any great strength.

Most of the lighter elements - especially hydrogen and oxygen - have been lost to space by the action of the solar wind. The atmosphere has been eroded of all its lighter components, leaving carbon dioxide and thus a runaway greenhouse effect.

The Earth's magnetic field protects the atmosphere from the solar wind. It has had a magnetic field for at least 3.7 billion years. 

Are Vast Amounts of Hydrogen Fuel Hidden Below Earth's Surface?

 

Are Vast Amounts of Hydrogen Fuel Hidden Below Earth's Surface?

The short answer is that we do not know! A longer answer can be found in THIS New Scientist Article.

A couple of emails ago I wrote about using ophiolites to produce hydrogen. Many people believe that you do not need to do that as there should be lots of hydrogen lurking below the earths surface. There is talk about quadrillions of tonnes. But so far only one deposit is known - (in Mali).

Finding other deposits is proving to be very difficult - unless they have been found and the finders are keeping quiet! We do not want to go down that rabbit hole! (A bore hole surely!)

I hope more evidence appears soon and we can stop following speculation.