Geology Johnson

Where I discuss Earth Sciences and anything else I feel like.

[geologyjohnson]

Geology For World Builders

New video! After several requests I'm making some videos explaining basics of #geology for #worldbuilders such as #fantasy and #scifi writers and their ilk. Check it out and share it below. #Worldbuilding

https://www.youtube.com/watch?v=O9gpQqL8dHM

[geologyjohnson]

Digital painting I made of the Earth as it would have looked around 1.6 billion years ago. The single super continent is called "Nuna".

[sh4rkguts]

[mossworm]

please enjoy this video of my leech, yes the two dots on the end are his eyes

[mossworm]

details:

- this is an omnivorous leech (possibly a Barbronia?) that eats worms and dead stuff. they cannot bite or draw blood.

-they wiggle like this to absorb more oxygen from the water, it's normal especially after they eat something

[geologyjohnson]

Weird Precambrian Microfossils

Here is one of the weird fossils I've been working on since getting back to Belgium. It's about 60 microns long, or 0.06 millimetres and 1.4 billion years old and no one in the lab has seen anything like it before. The texture is not just a surface pattern, the light areas are pits, the dark areas are raised tubes. There are multiple layers of tissue and structures that look like pore that could open and close. These features indicate the fossil is probably from a eukaryotic organism - those with complex nucleated cells. I don't think this level of detail has ever been preserved in a fossil this old before. Additionally, you normally need to look at rocks less than a billion years old to find fossils with this level of complexity.

This fossil is significant because it lived at a time when we did not think life this complex existed yet. This is a period of time called "The Boring Billion" where the Earths environment and biology were thought to have entered a period of stasis - e.g. nothing changed for a billion years. My work will join a growing body of research that shows this interval was anything but boring, and was actually a pivotal period in the development of our planet and the life that inhabits it.

[geologyjohnson]

1.5 billion year old micro fossil

FossilFriday a mid #Proterozoic #acritarch with the complex ultrastructure, sculpture, and ornamentation indicative of #protist #fossils This is a stack of ~60 images taken at 100x mag #Geology #Paleontology

[geologyjohnson]

1.5 Billion year old Eukaryote microfossil

Proterozoic #acritarch photographed in high res. This taxa appears to bud while undergoing torsion. This is made from focus stacking many images at high mag. Fossil is ~50 x 85 microns. The smallest resolvable objects on the full res version are ~ 500 nm. #Geology #Paleontology #Fossils #precambrian #tiny #geologyjohnson

[geologyjohnson]

Enigmatic microbial structures composed of silica plates, filamentous organic matter, and a single type of acritarch. This example is a mid-Proterozoic mudstone bedding plane. Details in the alt text.

[geologyjohnson]

Thin section Thursday A section through a cute little microbial tuft from the 3.22 Ga Moodies Group, South Africa. The tuft is composed of filamentous organic matter, silt, and clay. The overlying layer is coarser silt, clay, and early silica cement.

[geologyjohnson]

Undescribed Proterozoic Fossil

Fossil Friday Part of an undescribed mid Proterozoic critter preserved as an carbon compression on a deep water mudstone. You can see nice features like the regular spaces with dots in the middle. Image 1cm wide

[geologyjohnson]

#ThinsectionThursday early #Jurassic tempestites where #crinoids have been converted from calcite to glauconite. The conversion has even preserved the micron scale detail of the stereom. Each image about 5 mm wide. #geology #paleontology #echinoderm

[geologyjohnson]

Work in progress on a goniatite painting. What other critters should I add?

[geologyjohnson]

FossilFriday a 3.22 Ga #acritarch from the Moodies Group, South Africa. These were first described by Javaux et al in 2010. But they've not been found since. I'm looking for more of them using new unweathered sample material. Details in alt text #Geology #Paleontology

greyscale microscope image of a circular microfossil with a surface that is wrinkled and speckled, and has radial cracks at the edges. These features indicate that the fossil was probably a 3D vesicle that has been compacted. There is a black arrow that points to one of the larger folds, and a black 50 micron scale bar that shows the fossil is about 300 microns wide. original paper: https://www.nature.com/articles/nature08793

[geologyjohnson]

Ancient Microbial Mat

#ThinsectionThursday An extreme close up of a #Precambrian microbial mat. This sample is over 1 billion years old. Dirty grey-brown is silt and silica cement with amorphous organic matter. Orange brown is titanite, and the dark grey brown to black is filamentous organic matter. The image is about 0.25 mm across #Geology #Paleontology.

[geologyjohnson]

#Precambrian #acritarchs on a mudstone bedding plane. This acritarch is commonly found as these aggregates where the individuals are curled around each other. Note that they are partially buried, and intruded by an acicular mineral grain on the right. These observations indicate the acritarchs where already in this configuration when they entered the sediment.

#FossilFriday #Geology #Paleontology #acritarch

[geologyjohnson]

My first attempt at a paleoplanet. This is Earth around 3.2 billion years ago. The rocks I study are from the Moodies group which was being deposited on the edge of Vaalbara which is the lower continent. The other continent is called Ur. Some artistic license taken. #Geology #Paleontology

[geologyjohnson]

The secrets of shale

New video online now. Learn the secrets of shale! See some nice pictures of rocks! Watch me miss pronounce everyday words!