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Expert Pushing SSer
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Discussion Starter · #1 ·
OK, I understand USGS quad sheets, townships, ranges, sections (1-36), 1/4 sections, etc. But, explain what is happening when there are section numbers greater than 36? I have a map with 50 and 60 on it. The sections are little pieces of the theoretical 1 sq. mi. section (as stated 1-36). Do they count when you need to locate someone in the field? What's up? Edjimicate me. :)

Thanks!
 

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Witty McWitterson
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In my experience, Sections are only, and only have been 36 sq miles, by section. I'm too lazy. Did you try google?
 

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Expert Pushing SSer
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Discussion Starter · #3 ·
~martini~ said:
In my experience, Sections are only, and only have been 36 sq miles, by section. I'm too lazy. Did you try google?
Me lazy? ;) He he, yeah I checked out google, and even the USGS (shockingly), I think you mean 1 sq. mi. for each section, 36 sq. mi. for a township and range. Whatever.....taking the next caller? :)

Cheers!
 

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Uyyyyy, have to blow the cobwebs out of the brain attic for this one. I was a land surveyor before I went to college about 20 years ago so I may totally senile here, but I think that when you have a tract of land that falls into more than one section, or is not entirely within one section, then you start numbering that tract higher than 36.

Eeesh, don't quote me but maybe it's a starting point to get your answer.
 

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I've never seen one that goes higher than 36, but I've seen ones that don't bother to assign numbers. This usually happens near water bodies, rivers, and so forth where one state's layout starts getting funky with another's. I'd have to see the map to hazard a guess. Are the sections square, or I'm guessing the "little pieces of the theoretical 1 sq. mi. section" imply these are irregularly-shaped sections.

I'm not sure, but I seem to recall talking with someone at the Corps of Engineers once and they mentioned that sometimes those weird sections are given a more unique number to help distinguish them from others in the area, since they can get to be a real mess.

You might try calling your state's geologic commission and asking if they can enlighten you. I should probably be ashamed to admit I'm somewhat stumped, being a geologist and all.. but I've never really encountered something like that. What is the location? I might be able to take a look at it on TerraServer or if the state has some GIS database with topos.
 

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"I thought you were dead"
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There is a fairly in depth description of the Public Land Survey System at:

click here

Otherwise, here is a section of the article that might help explain the >36 sections per Township delima:

Because the grid is rectangular and the earth is round, adjustments must be made periodically; all sections cannot be one square mile nor all townships 36 square miles. These adjustments are done within each township by starting the sectional surveys of the township in the southeast corner and moving progressively toward the northwest corner. The northernmost and westernmost tier of sections—11 in all—are allowed to deviate from one square mile, but the other 25 are not. This method accommodates the curvature effects, and also allows for the correction of errors made during the surveying—which were not uncommon—without overly compromising the rectangular nature of the system.

The closer you are to the poles of the earth, the more "weird" the PLSS grid gets. Same goes for UTM and Geographic (latitude / longitude) grids.

Townships also get "weird" near the edges of a meridian or near a significant geographic feature that the original land surveyors had no desire to work within or upon (eg: large canyons, a cliff area, bodies of water, etc)

For laymen that need to better understand this problem, take a basket or soccer ball, and then try to tape a perfect grid on top of it, making sure that each grid cell is exactly the same shape and size.
 

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Expert Pushing SSer
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Discussion Starter · #8 ·
Thanks for the additional info all. I will have to admit, I am also a geologist. So, I too am embarassed. :D Anyways, for your entertainment I provide Exhibit A, a portion of the Woodburn, OR Quadrangle. Look at the mess! :madman: :eek: :rolleyes:
 

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Who's riding today?
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Man..... talk about personal cobwebs in the cranium.....

I graduated (or at least they wanted me out) from San Diego State University in 1980 with a degree in geography! I took two courses in cartography (it is a geography issue, not geology) and don't have your answer. Maybe it was all a dream but I swear I got out with a degree.........!!!

I love maps...... just not 100% sure of all the details. When passing thru Phoenix last Oct I visited an incredible map shop, they had a HUGE inventory and had several very good staff on hand. Keep "plotting"!

Chip
 

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Expert Pushing SSer
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Discussion Starter · #10 ·
CEB said:
(it is a geography issue, not geology) and don't have your answer. Maybe it was all a dream but I swear I got out with a degree.........!!!
Yep, ha ha. I think that CSULB was tired of seeing me for 9 years. ;)










Kidding.
 

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Expert Pushing SSer
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Discussion Starter · #12 ·
barnstormer said:
Ahhh... "Exhibit A" explains all...

Those are not section lines. They are land grant boundary lines. I had a hunch, though still had to check the USGS Topographic Map Symbol Chart.

Wow-wee... I can't believe it's taking three geologists and a land surveyor to figure this out. I'm a geo too.
Cool! Well, let's call it a day. We are all under payed, overworked. I vote for a beer. Race you all home! :thumbsup: :D
 

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Tree Hugger
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Meat Foot said:
Cool! Well, let's call it a day. We are all under payed, overworked. I vote for a beer. Race you all home! :thumbsup: :D

No offense Meatfoot, but if it took 3 geologists, and a land surveyor to read a map, I'd say yall are probably getting overpaid!!:p

What's the big deal anyways? How hard can it be to read a map? North is up, and South is down. :D
 

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If the Land Surveyor in question is me, can I just say that most of my time surveying was spent napping in the survey truck in between rounds of pinochle? Hehhhh!
 

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ali'i hua
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barnstormer said:
Ahhh... "Exhibit A" explains all...

Those are not section lines. They are land grant boundary lines. I had a hunch, though still had to check the USGS Topographic Map Symbol Chart.

Wow-wee... I can't believe it's taking three geologists and a land surveyor to figure this out. I'm a geo too.

yup. in some areas of these fine united states, if you go back far enough, you don't get parcel numbers (000-0000-000 or some ilk of such) but you were asigned a land grant number- usually they start above 36 especially in sectioned land (well, at least in CA, MI, and OH from what i've seen). makes life rough in reviews.

sorry- historic aerials and topo maps are part of the job.
 

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"If the terrain differs from the map, believe the terrain."
- Norwegian Boy Scout Handbook, in the section on map reading.

Not totally on point, but I like the quote anyway.
 

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Sasquatch said:
No offense Meatfoot, but if it took 3 geologists, and a land surveyor to read a map, I'd say yall are probably getting overpaid!!:p

What's the big deal anyways? How hard can it be to read a map? North is up, and South is down. :D
Well, in our defense it was kind of murky until the scan showed what kinds of lines were separating the areas. All of the kudos have to go to barnstormer, though. :)
 

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Expert Pushing SSer
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Discussion Starter · #18 ·
Sasquatch said:
No offense Meatfoot, but if it took 3 geologists, and a land surveyor to read a map, I'd say yall are probably getting overpaid!!:p

What's the big deal anyways? How hard can it be to read a map? North is up, and South is down. :D
None taken. Actually, we should all feel pretty good, even the engineers with masters degrees from good colleges could not figure this out. I knew we could shake out some good info on MTBR. And, remember, this is a cartography question, not a geological one :) He he he.
 
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