By the discussions I've had with surveyors in my country (Sweden), any coordinate descriptions of properties are deferred to the physical markers in the ground (cairns for older property, metal stakes for newer ones). This would only be an issue in properties that have never been surveyed (and marked) at all.
Straight borders might become crooked if they cross the crack though.
I am also in Sweden, and learned recently that a large part of my property seems to actually belong to the neighbour according to the online map! But there is a page in the relevant authority's website which clarifies that the online map can be 10s of meters off (in Swedish): https://www.lantmateriet.se/sv/kartor/vara-karttjanster/Visa...
There, it even explains some history and methodology for defining the borders. Mostly, they are defined by physical markers that hopefully the original surveryors left on the ground. I found a couple around my property (which is on hills so it's likely difficult to mark properly on a map from above) and it seems the borders are actually almost correct. As my fences have been up for over 20 years in the same location, I believe they also count now as de-facto borders now!
The official map of your property will not be exactly the same as the one on Lantmäteriet.se.
In more densely populated areas, there will be a local coordinate system, where each property is defined in terms of the neighbouring ones. This also applies to newly formed properties in old areas.
The property borders on digital maps are machine approximations of the mapping from the local coordinate system onto an absolute global coordinate system. This mapping can never be perfect, and it is often much less perfect than it could have been.
When the physical markers are missing or suspected of having moved from their original location (happens all the time for all sorts of reasons), Lantmäteriet will review the original documents of your and any number of neighbouring properties and deduce where the markers ought to be.
Regarding your fence, 20 years is very far from enough to establish "urminnes hävd". I suggest you wait another 100 years before you start assuming that they could act as facts on the ground in a property disputes! :-) And even then I wouldn't bet on it, unless the national archives are all destroyed...
I had to go back and check regarding "Urminnes hävd" (ancient custom). The creation of new instances of this for property rights was blocked back in 1970.
You can still use it, but then you must prove that the property right was an established ancient custom already before 1970. Anything that started after that will never qualify, no matter how much time passes.
My understanding of that type of "hävd", is that you need to have an official but incorrect deed of some sort, that remains uncontested by a true owner for 10 or 20 years.
Simply making uncontested use of the land is not enough.
I guess it is something that can happen quite easily in rural settings with very old property lines. Farmer 1 and 2 agree to some deal and a while later farmer 3 turns up and says "hey that's my land".
People lose property to coastal erosion all the time. Here there is a scheme to give some people replacement land further inland I think in some areas.
The natives lost something, to be sure, but I'm not sure it was property. Property is created when you kick everyone else out. I assume that's the rationale behind "property is theft," it used to be everybody's and now it's yours.
You're correct. They didn't lose property as they had no legal concept of ownership. Instead they lost their homes, their culture, and their lives. How lucky for them!
The level of respect is per treaty, a blanket statement cant be corroborated as many are not respected or dont have consensus amongst the affected people of being respected
You felt compelled to parade your ignorance by inserting this cheap shot about "Palestinians" into an unrelated discussion. What I mean by ignorance is joining the uninformed masses bleating about "genocide" and "colonialists". Presumably imagining that Jewish people arrived in Palestine de novo at some point in the 19th or 20th century and conquered the native Arab "Palestinians" there.
Area doesn't just disappear. I suppose that depending on what's on the land, your area might have a few more potatoes from your northern neighbors and fewer carrots you generously gifted to your southern neighbors.
You could alternatively just deal with your new jagged plot.
Worst case scenario, you're now the owner of the new Turkish Canyon.
I don’t think there’s a universally accepted solution but in California it would be up to the state to figure it out. It would be a great time to be a Real Estate lawyer after a quake there.
Essentially one affected party comes up with a proposed solution, files paperwork with the court, and then all the rest of the affected parties get together (under court supervision) to make whatever changes are necessary until the solution is fair. If the court agrees that it is a fair solution, it becomes final.
What was on your property is now on my property!