Questions tagged [fossils]

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1answer
457 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?
4
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1answer
342 views

I have found this fossil tooth, could it be pliosaur ? Or maybe theropod?

Lenght: 10 mm, striated, circular cross-section Site: Brno-Hády (limestone quarry), Moravia, Czech republic, central Europa Age: Jurassic, oxford The site is a good source of fossil shark teeth, ...
3
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1answer
539 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 ...
-5
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2answers
564 views

Why cannot people burn all the atmospheric oxygen? [closed]

We are told that photosynthesis, developed a couple of billion years ago has produced all the atmospheric oxygen. I wonder, why did the process stop? Why do modern plants prefer to recover the entropy ...
6
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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 ...
4
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1answer
500 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 ...
8
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2answers
21k 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 ...
0
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1answer
268 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 ...
8
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1answer
648 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
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2answers
1k 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-...
9
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1answer
408 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 ...
10
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1answer
171 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
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2answers
725 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?
11
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1answer
6k 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 ...
6
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1answer
914 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 ...
15
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2answers
425 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 ...
11
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1answer
480 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 ...

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