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Questions tagged [fossils]

The tag has no usage guidance, but it has a tag wiki.

15
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2answers
389 views

What, if any, paleoclimate data can be derived from stromatolite fossils?

Stromatolite fossils have a layered structure vaguely reminiscent of tree rings, which are a well-known source for climate data. Although the formation process of stromatolite layers is less seasonal ...
12
votes
4answers
5k views

Why are many fossils found in deserts?

Why are deserts famous for fossils? Is it a coincidence? Some examples: Giant Catfish Fossil Found in Egyptian Desert Chile's stunning fossil whale graveyard explained Giant Dinosaur Fossil Found ...
11
votes
1answer
419 views

What periods of the fossil record are most lacking in specimens?

What parts of the fossil record are most lacking in specimens? That is, if you were to trace the evolution of a modern mammal (humans, for example) from abiogenesis to now, which periods are the most ...
11
votes
1answer
5k views

How can I tell if a rock is really petrified wood?

I found a rock in the Mojave desert and it resembles a tree branch including what appears to be wood grain. Is there some test or observation that can be done at home to conclusively answer my ...
10
votes
2answers
151 views

Strange scar marks on pebble

My question is not specifically about identification of this piece of rock. Instead I am focusing on the origin of the scar marks on this rock. I have found this stone in the pebbles in the path. This ...
10
votes
1answer
157 views

How would a Mars rover identify a microbialite fossil?

I recently read of a company in Canada using robotic technology to study freshwater microbialites. Their claim is that greater understanding of terrestrial microbialites could help in the search for ...
9
votes
2answers
659 views

How do scientists determine the absolute or 'chronometric' date of fossils?

Absolute dating is the process of determining an approximate computed age of something like a fossil. How does that work?
9
votes
1answer
358 views

What geological processes can cause local biases in the fossil record?

What are the main geological processes that can cause local biases in the fossil record, e.g. when comparing species diversity or species occurances in different areas from the same time period? I ...
8
votes
1answer
240 views

What is the oldest fossil on Earth?

What is the oldest fossil ever found on Earth? Where and when was it found? What was the oldest fossil with a brain with 2 hemispheres ever found?
8
votes
2answers
11k views

How can I learn to spot fossils and fossil-bearing rocks on the Jurassic coast?

Due to a pleasant change in my circumstances, I have been to Lyme Regis several times recently, and it seems as though I'm going to be a regular visitor over the next few years. As a former biologist ...
8
votes
1answer
521 views

Is the Principle of Fossil Succession accurate?

After wondering on the validity of the principle of Original Horizontality, I'm now focusing on the principle of fossil succession. This principle states that : Fossils of species that did not ...
7
votes
2answers
963 views

Life on Earth previous to us

I've seen in several places that there seems to be an extinction cycle on Earth of approximately 27 million years. I've read this here: http://www.dailymail.co.uk/sciencetech/article-1294372/Life-...
7
votes
1answer
485 views

Identification of a rock from Kentucky [closed]

I was hiking the other day in southeastern Kentucky and ran across this rock on a river bank. I've never seen a rock like this before. Can anyone here identify it?
7
votes
1answer
267 views

What are Ordovican trace fossils, and what do they look like?

There are some unusual structures in recent images from the Mars Curiosity Rover's MAHLI (Mars Hand Lens Imager) shown in the Space.com article Curiosity Rover Spots Weird Tube-Like Structures on Mars....
6
votes
1answer
894 views

How can a non-geologist identify a rock? [closed]

I found a rock on a beach in north-east Evia, Greece. Half is light gray, and half is dark gray. There are white (or very light gray) thin lines that form swirls throughout, crossing the light/dark ...
6
votes
2answers
661 views

What is Oligo-Miocene radiation?

Some studies about Earth's fosilized plants/animals mention a "Oligo-Miocene radiation". Examples: Our study therefore strengthens previous suggestions that the absence of very large penguins ...
6
votes
1answer
293 views

Identify rock with circular features

I found this rock by the shore of Lake Ontario. It's light weight and it was grouped with some other rocks with the same patterns.
6
votes
1answer
67 views

Why the $\delta \, ^{18}\text{O}$ in foraminifera shells decrease with temperature even if the oceanic $\delta \, ^{18}\text{O}$ stay constant?

I understand why foram shells contain more $^{18}\text{O}$ when there are ice sheets present, since $^{16}\text{O}$ evaporates more readily and gets trapped in the ice, increasing the relative ...
6
votes
2answers
191 views

Fossil or Pseudofossil?

I found these rocks in the Oregon Coast Range many years ago and have always wondered whether the interesting image was a pseudofossil or an actual fossil. If it's a pseudofossil, any ideas on how it ...
6
votes
1answer
1k views

How to identify a predator's coprolite from an herbivore's?

I have a coprolite that is 8" by 5" and weighs 8 lbs. The shape is similar to a lumpy brain, the colors below outer crust are deep red and the crust is pastel green and grey. It has a strong density ...
5
votes
2answers
179 views

ID on a potential flint fossil

I was out in Swinley Forest in Bracknell(United Kingdom) last weekend. The area is a large pine forest but the ground is full of flint and is very sandy. I stumbled across a piece of flint and ...
5
votes
1answer
249 views

A sedimentary rock with only minerals

In my text book I came across this multiple-choice question A sedimentary rock consists of only minerals and lacks fossils, it could be classified as: i) a clastic sedimentary rock ii) a ...
5
votes
1answer
285 views

Circular patterns at bottom of rock, is it a fossil?

The image below was taken on a hike. Circular patterns at bottom (it is flatter on this face and round otherwise) appear either man-made or possibly it is a fossil. Any idea what this could be?
5
votes
1answer
141 views

Geological feature - what is it?

Hello, We were walking in Bundoran in Donegal County, Ireland today and we encountered the geological feature shown in the picture (from above from cliffs and from very close up at beach level). We ...
5
votes
1answer
320 views

Any idea what are these circular rock marks?

During a family trip in the Israeli National Trail in the Pora Stream part (31.496871, 34.770928), I noticed these circular rock marks. Any idea what are they?
4
votes
1answer
137 views

What are these lines on this stone?

I found this on Lake Ontario in Canada. I was wondering is there is anything special/out of the ordinary about it?
4
votes
2answers
298 views

Aligator or Dinosaur Fossil skin type rock

The more I looked at this stone and touched it, the more this thing looked like it was wrapped in some kind of reptile skin. It may just be a random rock. More photos if needed. Does this look like ...
4
votes
2answers
156 views

“Impression and pseudomorphism” in fossils

In a book on invertebrate paleontology I have (Treatise on Invertebrate Palaeontology, A) there is a diagram showing possible fates of a shell after the death of the organism. One of the possible ...
4
votes
1answer
411 views

Fossil or Beef Limestone?

I found the below sample on Monmouth Beach near Lyme Regis and I am unsure if it is a fossil or simply beef limestone. The beef limestone is from fibrous calcite layers within a shale (known as shales ...
4
votes
1answer
136 views

Can anyone identify this stone?

I found this rock at the weekend in the forest of Haigh Hall, Standish. It seems to be a solid mass of fibrous material. I have given it a scrub with warm water and a toothbrush just to get rid of ...
3
votes
5answers
543 views

Why does mineral oil occur below natural gas?

Why does mineral oil occur below natural gas? It was asked in our science book in the Geology section and I didn't get a clear explanation from the teacher.
3
votes
1answer
736 views

Why don't animals rot when trapped in amber? [closed]

I just saw an image of a gecko stuck in amber 58 million years ago. Why don't animals rot when they are trapped in amber? I've seen dry insects whose chitin shells persist for a long time away from ...
3
votes
1answer
106 views

What type of mammal does this fossil tooth belong to?

The fossil tooth was found western South Dakota in the early 1980s. I can't be sure on the location. It might have been collected from Belle Reservoir, near Belle Fourche, Butte County, South Dakota, ...
3
votes
1answer
116 views

Rock ID: sedimentary fossil from North Norfolk coast, UK

This palm-sized rock is from the beach at Eccles-on-Sea (North Sea coastline). I can see four types of material: A brown, slightly translucent, 6cm tubular fossil(?) that I can mark with a steel ...
3
votes
1answer
388 views

How old are Pecten fossils in general?

Many years ago, I found a piece of rock on a lakeside in Switzerland (see picture below). I think that it could be a "fossil" from some Pecten species (do you agree?). My question is: how old such ...
3
votes
1answer
58 views

Donation Options for Fossil and Mineral Collection

The father of a friend of mine passed away recently. He left behind an extensive collection of fossils and minerals. They include a saber tooth tiger skull, mastodon tooth, shark teeth, tons of ...
2
votes
1answer
139 views

How quickly can coral fossilize?

On a trip to Honduras a few years ago I visited one of the islands off its north coast with a friend and went to a section of it mostly with nothing but residences which looked far less visited by ...
2
votes
0answers
75 views

What kind of tooth is this?

Please help me identify this tooth and the era its from. I found it in Panama City Beach Florida. Its cold and hard when i bite it. It looks very old. Possibly a shark tooth?
2
votes
0answers
234 views

Are fossils in slate 3 dimensional or does the slate split open at the weakest point where the flat imprint of the fossil is found?

In this picture you see a fossil of an Ammonite. When you break a slate with a hammer it will fall apart so sometimes you can find a fossil. But is this fossil only there in the slate just at the ...
1
vote
1answer
84 views

Who can it belong to? fossil tooth

**Tooth was found in Baltic Sea, near Lithuanian coast, **
1
vote
2answers
124 views

What is this rock we found in a store?

We found this rock at a mineral and jewelry store. The gal wrote down what it was and we cannot find what we think she wrote on the internet anywhere. She wrote Mcstrodlite.
1
vote
2answers
64 views

What is this stratefied limestone sphere?

What is this stone from the alps of provence? It's two spheres, one of them is made of at least 25 layers.
1
vote
1answer
114 views

What type of fossil is present in this rock from northern Ohio?

I need some help identifying this fossil. I found the rock 30 years ago along the Cuyahoga River in northern Ohio. Northern Ohio is glaciated so it is possible that the specimen was transported to ...
1
vote
0answers
66 views

Fossil or just strange lines?

Found this in Souris, Manitoba. The lines are on both sides. What could this be?
1
vote
0answers
61 views

Rock / Fossil ID?

Please see link below if anyone can help ID. I think the little claw looking thing is a fossil? The red rock is smooth,Matt in some places and semi glossy on some of the sides. The black rock has ...
1
vote
0answers
58 views

Is this a fossil or a mark on the stone

Found this rock during a walk along the coast and I can't tell weather the white line is a fossil or just a mark on the rock. Any help in identifing weather this is a fossil or not would be ...
0
votes
1answer
257 views

Are there any geological periods found on top of each other that have dinosaurs of that period with in them?

In diagrams, It is common to depict geological periods to be directly on top of each other with fossils of that period within them. When looking for evidence of this, I have only found examples of ...
0
votes
2answers
98 views

Is this a fossil

It this a stromatolite fossil? If it is, it’s probabaly at least 1 billion years old
0
votes
1answer
62 views

Please identify markings

these are the other rocks I found near Lake Ontario
0
votes
1answer
85 views

Can someone please help me identify what this is… stromatolite…coral…or neither…help [closed]

Hi I'm trying find out what kind of rock this is.... I have a chunk the size of akeg of beer looks like muddy coral on the bottom and coral like inside and agatized sponge or coral or something else ...