Jump to content
Steve Herschbach

Light Detection And Ranging (LiDAR)

Recommended Posts

This is pretty neat stuff, and I think the applications for prospectors and relic hunters are obvious...

http://news.nationalgeographic.com/news/2014/01/140103-new-england-archaeology-lidar-science/

  • Like 1

Share this post


Link to post
Share on other sites

Wish I had views of my area like this, were literally on the oregon trail. Several places I heard of here are forested hiding the old campsites. Also the old stage stops would probobly show up. Pretty cool stuff, instant history.

  • Like 1

Share this post


Link to post
Share on other sites

"Something there is that doesn’t love a wall,

That sends the frozen-ground-swell under it

And spills the upper boulders in the sun,

And makes gaps even two can pass abreast."

Robert Frost nailed it.

All the New England farmers got tired of stacking rocks and moved to Oregon over the Oregon trail. "Abandoned New England Farms" were all the rage in the early 20th century for city folks to fix up.

Share this post


Link to post
Share on other sites

In Nevada, where heavy vegetation is nearly unheard of, you can see pretty much everything with Google Earth.

In the heavily forested sierra gold country, Lidar would be amazing.

Share this post


Link to post
Share on other sites

That's world class stuff right there.  Can't wait to see more of this!!

 

Thanks for sharing.

 

Kenny

Share this post


Link to post
Share on other sites

More on LiDAR - they discovered Roman gold mines in Spain! We have detector guru engineer Dave Johnson to thank for this link:

 

http://www.laboratoryequipment.com/news/2014/11/airborne-laser-finds-roman-goldmines?et_cid=4277812&et_rid=281012844&type=cta

 

Now if we could just see underground like that!

post-1-0-68822300-1416597525_thumb.jpg

Share this post


Link to post
Share on other sites

Low resolution raw LIDAR data is publicly available for free for about 1/3 of the United States, mostly the east coast and developed areas. High resolution LIDAR (1-3 cm) is available in a few areas. Mostly for environmental studies or only available privately.

 

Without LIDAR we have to rely on DEMs (Digital Elevation Models) for elevation data. These are mostly just a rehash of the old paper topo maps with hand drawn elevation lines converted into even lower resolution digital point shapes represented by light and dark shades on an artificial black and white image. The shades of gray of each pixel represent different elevation values. These DEMs have a high factor of human input error. Mountains and valleys sometimes appear wher there is nothing but a road or a visually confusing feature on the original topo map. If I were to describe the conversion method for these topo's derived DEMs I'm sure you would be in awe of the influence of primitive technology in our "modern" lives.

 

LIDAR is really just a (sometimes) higher resolution version of this system with the difference being the LIDAR points are defined by direct reflection of a laser light rather than ground observations with optical equipment, geometry and trigonometry - traditional survey equipment and methods. The final result in either case is still a grid of values most usually visualized and stored as a photo image in shades of gray. Although just about any data storage format will work humans still naturally understand complex data with their eyes better than any other sense.

 

The features you see on your link were buried in the original LIDAR data. A lot of post processing (number crunching) is necessary to turn the raw data into detail like you see on the website linked. In other words the LIDAR system itself is not discriminating out the trees and ground cover. That is done by applying some pretty complex algorithms to the data after the fact. All of that processing actually lowers resolution and accuracy. To be truly effective for any particular purpose those algorithms are usually customized to the project requirements.

 

We use LIDAR on some of our private mapping projects along with matching high resolution georectified aerial imagery. This can reveal several features you could never see from the ground or the air. We can build 3D models that very closely conform to reality and move through those models in three dimensions. This is a very realistic process and allows us to include measured, extrapolated or even sensed data for underground features. Mining companies love this stuff, not so much for project management but for making presentations for investors.

 

The size of the data involved is a very real problem. Terabytes of data are needed for even a small area and processes take a very long time to run on data that size.

 

Just obtaining the data can be a very long process. We can order a LIDAR scan of just about anywhere in the world but the logistics of producing that scan can be overwhelming. A good high quality scan requires several manned precisely located ground stations as well as some very expensive aerial equipment. Just getting the time booked can be a long wait and getting the skilled ground and air crews working together under ideal conditions can be a virtual impossibility. Add in the difficulty and expense of placing those ground crews on landlocked parcels, hostile territory, difficult terrain or legally challenged access can make the entire process prohibitively expensive and slow.

 

Like much of what is possible in theory the theoretical 1 cm accuracy of a LIDAR scan is rarely if ever achieved in real life.

 

This is not a new technology, it's been around since the 1960's, but until now the technology to push it into the realm of useful and affordable has been lacking. That is changing and I look forward to a time when high resolution ground scans can be considered an accessible tool for many professions. Until then it is a gas to work with small areas in high definition, I only wish more clients could afford the time and money involved in high resolution LIDAR.

  • Like 4

Share this post


Link to post
Share on other sites

Wow Clay, excellent insight and details. Thanks! With increasing availability of computing power things can only get better. I still can't believe I have two terabytes of storage sitting in front of me as I type, and it wasn't even expensive.

Share this post


Link to post
Share on other sites

That two terabyte drive will fill up faster than you can believe Steve. It's the old house rule. Given ANY size house a man will eventually overfill it with stuff. Big house... lots of stuff.

 

Memory and storage have gotten a lot cheaper. That helps a lot.

 

Processing power not so much. To get that doubling of computer power for the next step something new is going to have to come around. The traditional chip isn't getting appreciably faster. We stack processors and memory pretty deep already but that only helps - it doesn't solve the problem.

 

With everyone going to phones and tablets for their day to day computer needs there isn't much incentive for chip makers to take big leaps to new technology. It's all about lower power consumption and less heat these days.

 

LIDAR will provide new insights into the world we live in. With stuff like retina screens and bigger brighter displays the consumers are there to enjoy those insights but the production is going to be slow and expensive for the foreseeable future.

Share this post


Link to post
Share on other sites

 Big house... lots of stuff.

 

 

 More money.... More problems   :)

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Similar Content

    • By Steve Herschbach
      I keep an eye on various forums just in case something new of interest pops up. I thought I would list the ones I frequent most often here. Feel free to add to the list.

      The prospecting forums I visit now and then are:

      TreasureNet Gold Prospecting Forum
      Very active gold forums

      Findmall Prospecting Forum
      General prospecting

      Alaska Gold Forum
      General prospecting with Alaska emphasis
      The ICMJ Prospecting & Mining Forum
      Many sub-topics relating to prospecting and mining

      Canadian Gold Prospecting Forum
      Very active forum with many sub-topics

      And now the metal detecting forums:

      Findmall Forums
      Detector model specific sub-forums

      TreasureNet Forums
      Huge number of treasure hunting topics
      Friendly Forums
      Very active forums on a wide range of metal detecting subjects

      Tom Dankowski Forum
      Focuses on technical aspects of detectors

      The Arizona Forums
      All good, tend towards Minelab and Arizona but more varied of late
      Rob Allison's Nuggethunting Forums
      Chris Gholson's Arizona Outback Forums
      Bill Southern's Nuggetshooting Forums
       
      What's happening in Australia?
      Australia Gold Detecting & Prospecting
      Prospecting Australia
    • By Ridge Runner
      I’d said something about going to a Treasure Show this weekend and I’m back with a new book on Equinox Series Detector.
      I haven’t had a lot of time to read over it but did take time to scan it. With that said you want to know what I think of the book.        All I will say is spend the money to get a pirinted copy of the instruction manual for the Equinox. Then spend the time reading it and when you’re not sure about something read it over again.
      Chuck
    • By SittingElf
      We are going to be moving to Tinker AFB, OK in June, but in the meantime, while still based on Eglin AFB, FL, I have been researching old, now demolished family housing areas to hunt before we leave.
      I have discovered a major housing area, where all the homes were built between 1955 and 1962. Still standing in 1969, but now demolished and open fields. Very easy to research using NETRonline Historic Aerials against current Google Satellite maps.
      The kicker of this area is that it is on-base, and due to very restricted access, these fields are very likey virgin for hunting. I expect a lot of silver, wheaties and more in the front areas of these homes, as well as the always-open fields behind the housing circles, where kids would play, and parties held. Only hunting them will prove out my theory, but I have four remaining weeks at Eglin to find what I can!
      Here are the Aerial vs. current satellite pics.  After we leave, I hope someone into MD'ing will be assigned to Eglin and find this post. (Of course, I hope I've already recovered ALL the silver!! LOL)

    • By phoenix
      I was going through my computer looking at different stuff that I had forgotten I had and I came across this shortcut to the archives of Gold Net Australia.   Gold Net Australia Online went from 1999 to 2002 and remarkably, it`s still there.  Probably not of great interest to people in the States, but if you enjoy reading about coil developement from 20 yrs ago, or accommodation, or a review of the GP Extreme,  or divining rods, or storys of big finds or just pictures of beaut nuggets, there might be something here of interest.
      http://www.gold-net.com.au/archives.html
    • By tboykin
      Bom dia! I had the unique opportunity thanks to my job at White’s to do some work in Brazil and wanted to share some pictures from our trip. First things first, ouro!

      The soil here is nasty. Even the most expensive PIs struggle to balance out the mineralization. Add the humidity, 120 degree heat, and blazing sun and you have a great area to challenge a gold detector.

      Garimpeiros make their living off the gold they find. Some are dangerous but most of the ones we met were friendly enough to talk about gold and detectors. Just don’t get between them and their gold unless you want to disappear in the jungle.

      One of the places we went that was “hunted out” gave up a chunky rock that was just a whisper of a signal. When we cracked it open we found this tiny crystalline nugget.

      After breaking the tiny tree nugget off I could see that the gold continues down into the rock.
      Sad to be leaving but I made some new friends while working in the Brazilian sun.

      -T
    • By Steve Herschbach
      When Chris Ralph and I were down in Phoenix I was fortunate that Chris lined up a dinner with Barry and Leigh, the brilliant couple behind the new non-profit educational organization, Land Matters. The website at http://www.mylandmatters.org/ is your constantly expanding source of land related information, including:
      Library - A Library full of free maps, guides, books, tutorials and reference materials.
      Maps - Interactive maps for your area of interest. More being added every week.
      Articles - Factual articles written by those in the know. Information that you can rely on.
      Resources - Links and contacts to other communities of knowledge.
      Outreach - Programs that engage the community directly. Seminars, outings, trainings etc.
      I am far from done checking it all out myself, but this looks like something we should all consider getting on board with and supporting if possible. Check it out. I have added this banner to the rotating collection in the upper left corner:

      and added them to my links list
      Barry and Leigh, very nice meeting you, and keep up the great work!
      Here is a link to the new interactive land management status map http://www.mylandmatters.org/Maps/Management/GetMap

×