Swirling red and orange sandstone in Valley of Fire State Park, Nevada, under a blue sky.

Was Nevada underwater?

A state is not a point, and this is the emptiest point on the site. Four of the five ages below have no witness of any kind — no rock that speaks, no fossil near enough to count. Everything this page knows sits at one moment, around 250 million years ago, and amounts to 57 fossils. All 57 are recorded as sea creatures. At that one age the rock agrees with them, which is the only place on this site where every witness says the same thing — and 4 blank rows underneath it, which is the rest of what there is to know.

Real photograph · 301131619/Shutterstock.com · Shutterstock Standard (free image collection, API) License

The answer, age by age

Five ages in the past of this place, each one a window rather than a day. Each says which witness spoke — and where our evidence cannot answer yet, it says that too.

250MaThe rock of the region says sea
200MaOur evidence has no witness here
150MaOur evidence has no witness here
100MaOur evidence has no witness here
66MaOur evidence has no witness here

“Ma” means millions of years ago. The dashed mark means our sources have nothing for that age — which is a finding, not a fault.

One age speaks, and everything agrees with it

At 250 million years ago the rock database calls the rock around here marine, fossils are recorded both locally and across the wider region, and every one of the local fossils is a sea creature. Nowhere else on this site does every witness say the same thing at the same age.

Why that is not the same as being sure

These are not three separate checks on one question. Rock records where sediment settled. A fossil records where somebody dug it up — which is not where the animal lived, and not necessarily where it died. When both point the same way you have two descriptions pointing the same way. You do not have a proof, and this page does not offer one.

The other 4 ages — 200, 150, 100, 66 million years ago — have nothing. Not a thin answer: no answer. No rock unit that records an environment, and no fossil near enough to be grouped with them.

It would be easy to let the one loud age speak for the quiet ones, and that is exactly what this page will not do. An age with no evidence is not an age when nothing happened. It is an age nobody has dug.

Travel back in time

Four of these rows are blank and one is not. The blank ones are the honest majority of this page, and they are printed at the same size as the row that has something to say.

250: million years agojump to the evidence250 million years ago, the plate model puts this ground almost on the equator. Published models disagree by about 4.6° of latitude here — a few hundred kilometres — so it is one model's answer, not a photograph.
200: million years agojump to the evidence200 million years ago, the plate model puts this ground about 19° north of the equator. Published models agree more closely here, within about 2.2° of latitude, but it is still one model's answer rather than a photograph.
150: million years agojump to the evidence150 million years ago, the plate model puts this ground about 28° north of the equator. Published models disagree by about 4° of latitude here — a few hundred kilometres — so it is one model's answer, not a photograph.
100: million years agojump to the evidence100 million years ago, the plate model puts this ground about 40° north of the equator. Published models agree more closely here, within about 2.6° of latitude, but it is still one model's answer rather than a photograph.
66: million years agojump to the evidence66 million years ago, the plate model puts this ground about 44° north of the equator. Published models agree more closely here, within about 0.7° of latitude, but it is still one model's answer rather than a photograph.

What was the water doing?

Five ages, oldest first. Each one has two kinds of witness — the rock of the wider region, and the fossils dug up near the town — and they are kept apart on purpose, because they are answers to different questions.

Each age here is a marker on the timeline, not a single day. The evidence that belongs to it comes with an age range of its own that overlaps the marker — so it can tell you what this stretch of time was like, and never what was happening on one exact date.

The rock of the region says sea

Around 250 million years ago

250 million years ago, the plate model puts this ground almost on the equator. Published models disagree by about 4.6° of latitude here — a few hundred kilometres — so it is one model's answer, not a photograph.

The rock of the region

Across the wider region, the rock from 250 million years ago — the Thaynes Fm — was laid down in the sea. That is a statement about roughly 23,000 square kilometres of region, centred about 45 km from the town — not about the ground under one street.

The fossils dug up nearby

One fossil dug up near Ely has an age range covering 250 million years ago: 1 from the sea, 0 from land. It was found about 43 km away — near the town, never under it.

Our evidence has no witness here

Around 200 million years ago

200 million years ago, the plate model puts this ground about 19° north of the equator. Published models agree more closely here, within about 2.2° of latitude, but it is still one model's answer rather than a photograph.

An open question

Neither of the evidence sources we use can answer this one: our regional rock record holds no unit for 200 million years ago at this point, and no fossil dug up nearby covers that age either. That is a real gap in the evidence, not a gap in the past — and saying so is more useful than guessing.

Our evidence has no witness here

Around 150 million years ago

150 million years ago, the plate model puts this ground about 28° north of the equator. Published models disagree by about 4° of latitude here — a few hundred kilometres — so it is one model's answer, not a photograph.

An open question

Neither of the evidence sources we use can answer this one: our regional rock record holds no unit for 150 million years ago at this point, and no fossil dug up nearby covers that age either. That is a real gap in the evidence, not a gap in the past — and saying so is more useful than guessing.

Our evidence has no witness here

Around 100 million years ago

100 million years ago, the plate model puts this ground about 40° north of the equator. Published models agree more closely here, within about 2.6° of latitude, but it is still one model's answer rather than a photograph.

An open question

Neither of the evidence sources we use can answer this one: our regional rock record holds no unit for 100 million years ago at this point, and no fossil dug up nearby covers that age either. That is a real gap in the evidence, not a gap in the past — and saying so is more useful than guessing.

Our evidence has no witness here

Around 66 million years ago

66 million years ago, the plate model puts this ground about 44° north of the equator. Published models agree more closely here, within about 0.7° of latitude, but it is still one model's answer rather than a photograph.

An open question

Neither of the evidence sources we use can answer this one: our regional rock record holds no unit for 66 million years ago at this point, and no fossil dug up nearby covers that age either. That is a real gap in the evidence, not a gap in the past — and saying so is more useful than guessing.

What was dug up nearby?

Every fossil here was dug up around Ely and none of them beneath it, so each row carries the distance. They all belong to one age, which is why this list is short and entirely of one kind.

Around 250 million years ago

A Dixieceras lawsoni from around this time (its own age range is 241.464–243.43 million years) was dug up about 7.0 km from here.
A Marcouxites spinifer from around this time (its own age range is 241.464–243.43 million years) was dug up about 7.0 km from here.
A Brackites vogdesi from around this time (its own age range is 241.464–243.43 million years) was dug up about 7.0 km from here.

We show these places to the nearest few kilometres rather than pinning them exactly. The scientists who recorded them know the spot far better than that — the full record is one click away in the Paleobiology Database, and it is free for anyone to read. We round them here because a map made for children is not a map for digging things up, not because anything is being hidden.

What changed?

The plate model gives this ground a position at every age, moving north as the page comes forward. A position says where a piece of the surface was and nothing about what covered it.

The rock at the surface today is younger than all of it. The geological map of this exact point returns Cenozoic sedimentary rocks (Cenozoic), Quaternary sedimentary (Cenozoic), Alluvium, undifferentiated (Cenozoic).

Nevada is over a thousand kilometres from end to end. This is a box about a hundred kilometres across, and the state's own capital returns two fossils in the same window.

Try it yourself

The animals in this record lived in water in a place that is now high, dry desert. The water did not vanish; it went somewhere else, and it is still going round.

Do the dinosaur water maths

For school

A good page for the difference between no evidence and evidence of nothing. Four ages here are silent, and silence is the commonest thing in this record — worth sitting with before reaching for the one age that talks.

If our sources hold nothing for four ages out of five, what should you write about those four? Is 'we do not know' an answer or an admission?

How sure are we?

Column facts describe an area of thousands to tens of thousands of km², centred tens of kilometres from the town coordinate. They are claims about a region, never about the rock beneath the town.
Fossil facts are a bounding-box sample around the town, each with its own distance from it; a fossil is never "here". The absence of fossils is not evidence of the absence of life — only of the absence of a recorded, published dig in this box.
Positions are model outputs, not observations. Independent plate models disagree by hundreds of kilometres at these ages, and that spread is the honest size of the uncertainty.
The land/sea question is answered only by the regional rock and the local fossils, separately, and never by the reconstruction — which says where this ground was and cannot say whether it was wet. There is deliberately no single field holding a one-word answer, because answering in one word would require merging a regional claim with a local one (CLAUDE.md rule 5). The nearby fossils are reported as a census of what has been found — which kinds are present, and how many of each — and never counted into a verdict: occurrence records are not statistically equivalent observations, so a plurality of them cannot establish an environment (science review, 2026-08-30).
Fossils are binned to their nearest slice age by age-range midpoint, with boundaries at the inter-slice midpoints 83, 125, 175 and 225 Ma. Those boundaries are an editorial choice, not a published stratigraphic scheme; a reviewer may prefer stage boundaries. Every occurrence keeps its own age range so the choice can be re-examined.

Sources

Macrostrat — the rock of the regionRead from version 2.3.9 of its data service on 2 September 2026.Peters, S.E. et al. Macrostrat: a platform for geological data integration and deep-time research. https://macrostrat.org, accessed on (date)Palaeogeography: Wright, N., Zahirovic, S., Müller, R. D., and Seton, M. Towards community-driven paleogeographic reconstructions: integrating open-access paleogeographic and paleobiology data with plate tectonics. Biogeosciences 10:1529-1541
The Paleobiology Database — the fossils dug up nearbyPBDB publishes no dataset version string; the data-service path (data1.2) and the datainfo access_time bound this claim.Fossil occurrence data from the Paleobiology Database (https://paleobiodb.org), released under CC0 1.0.Palaeo-coordinate cross-check (Paleobiology Database `pgm=gplates`): Wright et. al., 2013; Towards community-driven paleogeographic reconstructions.Palaeo-coordinate cross-check (Paleobiology Database `pgm=scotese`): Scotese, C.R., 2021. An Atlas of Paleogeographic Maps: The Seas Come In and the Seas Go Out, Annual Reviews of Earth and Planetary Sciences, v. 49, p. 669-718.Palaeo-coordinate cross-check (Paleobiology Database `pgm=seton`): Seton et. al., 2012; Global continental and ocean basin reconstructions since 200 Ma.
The EarthByte plate model — where this ground used to beMULLER2019 version 3.0, run with pyGPlates 1.0.0, licensed CC BY 4.0.GPlates: Müller, R. D., Cannon, J., Qin, X., Watson, R. J., Gurnis, M., Williams, S., Pfaffelmoser, T., Seton, M., Russell, S. H. J., Zahirovic S. (2018). GPlates: Building a virtual Earth through deep time. Geochemistry, Geophysics, Geosystems, 19, 2243-2261. https://doi.org/10.1029/2018GC007584Reconstructions computed with the GPlates Web Service (EarthByte Group, The University of Sydney).Plate model: Müller, R. D., Zahirovic, S., Williams, S. E., Cannon, J., Seton, M., Bower, D. J., Tetley, M. G., Heine, C., Le Breton, E., Liu, S., Russell, S. H. J., Yang, T., Leonard, J., and Gurnis, M. (2019), A global plate model including lithospheric deformation along major rifts and orogens since the Triassic. Tectonics, vol. 38, https://doi.org/10.1029/2018TC005462. Licensed CC BY 4.0.Plate model: Zahirovic, S., Eleish, A., Doss, S., Pall, J., Cannon, J., Pistone, M., Tetley, M. G., Young, A., & Fox, P. (2022). Subduction kinematics and carbonate platform interactions. Geoscience Data Journal, 9(2), p.371-383. Licensed CC BY 4.0.Coastline and static-polygon data by the EarthByte Group, licensed CC BY 3.0 Unported.

This record was assembled on 2 September 2026 from the datasets above. The ancient positions are reconstructions from a published plate model, not observations.

Where to next

Back to the start