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Lidar Reveals 650-Square-Mile Maya Site Hidden Beneath Guatemalan Rain Forest

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Re: Lidar Reveals 650-Square-Mile Maya Site Hidden Beneath Guatemalan Rain Forest

#31

Post by BoxOfRain »

spaceman_2020 wrote: post #4

If I was a billionaire, I’d commission a lidar survey of the entire planet. The amount of stuff that seems to be hidden beneath forest and snow and mud and ocean is absurd.

If I was obscenely wealthy I'd do the same for the seas and oceans, there's got to be so many fascinating wrecks out there as well as natural formations we know nothing about yet that sonar could pick up. Shipwrecks often have a limited lifespan for things to be preserved too, for example there's very little left of Lusitania's wreck that resembles a ship any more just a rusty debris field.

Re: Lidar Reveals 650-Square-Mile Maya Site Hidden Beneath Guatemalan Rain Forest

#32

Post by GordonS »

spaceman_2020 wrote: post #4

If I was a billionaire, I’d commission a lidar survey of the entire planet. The amount of stuff that seems to be hidden beneath forest and snow and mud and ocean is absurd.

Any napkin figures for how much that would cost, and how long it would take? The results could be incredible...

Re: Lidar Reveals 650-Square-Mile Maya Site Hidden Beneath Guatemalan Rain Forest

#33

Post by maxerickson »

GordonS wrote: post #32
spaceman_2020 wrote: post #4

If I was a billionaire, I’d commission a lidar survey of the entire planet. The amount of stuff that seems to be hidden beneath forest and snow and mud and ocean is absurd.

Any napkin figures for how much that would cost, and how long it would take? The results could be incredible...

One way to sort of do it would be to poke at how much 3dep has cost so far and extrapolate from there. Hard to figure that though, with it being an aggregation of a bunch of other programs.

Re: Lidar Reveals 650-Square-Mile Maya Site Hidden Beneath Guatemalan Rain Forest

#34

Post by _8j50 »

DiscourseFan wrote: post #25
kristopolous wrote: post #15

It's a shame to think of all the ancient literature and rich history we've lost from these civilizations. I'm sure they had their Homers and Platos.

Well, maybe. But people still speak Mayan today and they've retained the legends and stories which are depicted on the iconography and actually written in the script, that's how we were able to decipher and read it. I don't mean to sound like a cultural darwinist, but Athens and the library of Alexandria were razed to the ground and yet we still have Plato today because everybody who got their hands on his writings d…

> perhaps even from civilizations far larger, have simply disappeared, like the Egyptian materials for over a thousand years.

What you're missing is a history of conquest. Greece and Rome had a very intertwined cultural exchange. It wasn't just alexander that conquered land all over (all the way to india) and I am sure you know of how rome invaded it's way to the point they needed two emperors.

Civilizationd in america invaded each other but not the rest if the world. Same with Africa (outside of Egypt and few minor regionally invading countries). Even in asia, chinese never invaded india. Now Genghis obviously did more invading than alexander so I'd be interested in how much culture and history he spread but I think Rome is what made a difference in the western part of the old world. They built roads and encouraged people from different parts of the empire to travel and trade. Genghis had a habit of killing everyone that resisted but the romans kept them alive as slaves.

American culture and literature for example, I am sure will last many centtiries in other cultures.

Re: Lidar Reveals 650-Square-Mile Maya Site Hidden Beneath Guatemalan Rain Forest

#35

Post by maxerickson »

d--b wrote: post #22

Is there some kind of openstreetmap layer where lidar-surveyed sites are aggregated? It'd be nice

The US has 3dep, which is a USGS program to aggregate and publish various federal and state data.

Not really the same thing you are talking about, and not global, but it can be fascinating to look at. You can see old logging railroads and things like that in Michigan, and trace them to where they collected and dumped into rivers.

Re: Lidar Reveals 650-Square-Mile Maya Site Hidden Beneath Guatemalan Rain Forest

#36

Post by unwind »

unwind wrote: post #10
zznzz wrote: post #5

what kind of lasers / lidar technology is this that is not reflected by trees?

Good question! According to [1], they rely on finding holmes in the foliage: Lidar, of course, does not actually see through vegetation. Rather, it sees through holes in the foliage. Some of the multiple laser pulses it emits simply find openings between leaves and branches, in much the same way that sunlight filters through the forest canopy, continuing down to the ground. [1]: https://www.gislounge.com/next-generat…

Uh, also, that should be "holes", they are not looking for a British fictional detective in the dense foliage of Central America's jungles. Thanks, phone. :|

Re: Lidar Reveals 650-Square-Mile Maya Site Hidden Beneath Guatemalan Rain Forest

#37

Post by DiscourseFan »

_8j50 wrote: post #34
DiscourseFan wrote: post #25

Earlier quoted context omitted.

Well, maybe. But people still speak Mayan today and they've retained the legends and stories which are depicted on the iconography and actually written in the script, that's how we were able to decipher and read it. I don't mean to sound like a cultural darwinist, but Athens and the library of Alexandria were razed to the ground and yet we still have Plato today because everybody who got their hands on his writings d…

> perhaps even from civilizations far larger, have simply disappeared, like the Egyptian materials for over a thousand years. What you're missing is a history of conquest. Greece and Rome had a very intertwined cultural exchange. It wasn't just alexander that conquered land all over (all the way to india) and I am sure you know of how rome invaded it's way to the point they needed two emperors. Civilizationd in ameri…

>American culture and literature for example, I am sure will last many centuries in other cultures.

Who can say?

You're right that Greece and Rome had very intertwined cultural exchange, but that was only after Greece had been conquered; again, that doesn't explain why Platonic philosophy was so influential outside of Greece and Rome.

And yes, the American civilizations didn't invade people from other parts of the world, but to them they did, because their immediate area was the world, and I'm sure if the Mayan civilization never collapsed they would be a colonizing force not unlike the Europeans. Appropriating land and labor for use in capital exploitation is not a distinctly European phenomenon.

Re: Lidar Reveals 650-Square-Mile Maya Site Hidden Beneath Guatemalan Rain Forest

#38

Post by Rebelgecko »

RaSoJo wrote: post #19

Let us bid adieu to that chunk of rain forest. First them archeologists will go scrounging, followed closely by the tourists. Do these 'historic' finds serve any purpose for our future generations? Or would those trees have served our children better?

I don't think any of those things you fear came to pass after El Mirador was discovered. Why would this site be any different?

Re: Lidar Reveals 650-Square-Mile Maya Site Hidden Beneath Guatemalan Rain Forest

#39

Post by heliodor »

spaceman_2020 wrote: post #4

If I was a billionaire, I’d commission a lidar survey of the entire planet. The amount of stuff that seems to be hidden beneath forest and snow and mud and ocean is absurd.

Anyone know how much LIDAR surveys cost? Would love to hear some numbers!

Re: Lidar Reveals 650-Square-Mile Maya Site Hidden Beneath Guatemalan Rain Forest

#40

Post by heliodor »

maxerickson wrote: post #35
d--b wrote: post #22

Is there some kind of openstreetmap layer where lidar-surveyed sites are aggregated? It'd be nice

The US has 3dep, which is a USGS program to aggregate and publish various federal and state data. Not really the same thing you are talking about, and not global, but it can be fascinating to look at. You can see old logging railroads and things like that in Michigan, and trace them to where they collected and dumped into rivers.

Catalog map is at:

https://apps.nationalmap.gov/lidar-explorer/

Click on a covered area, click one of the green icons listed next to each data set, then click on Potree Viewer in order to get to the 3D viewer (Potree in this case; I haven't tried the other one much).

Scroll down the sidebar and change the dropdown that says "intensity" to say "elevation". Right below that, tweak the slider bar to select the min and max elevations so that the landscape you're looking at gets colored with all the colors. At the very top, reduce the radius to 0 and increase the strength to 1.0. And if your hardware can handle it, increase the point budget to whatever is still responsive. Lastly, under filters, deselect everything except ground, if you want to see the ground instead of vegetation and buildings.

Also worth mentioning is the shaded relief derived from all this data, which you can find at:

https://apps.nationalmap.gov/3depdem/

It's very detailed and is a great starting point for your exploration of an area before jumping into the 3D viewer.

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