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Help me determine Line Parent #3298
Back To Discussion List Written: 2010.06.07 by: Dean Richards

I've added Mount Mussen to the database, from the Atlin Lake area. I've been able to to figure the key saddle, but I don't know know how to choose the Line Parent, do to the fact that all candidates are in a different direction from the key saddle. The main candidates are something on the Mount Caplice massif (which has yet to be added to the database, but whose summit is at 59:11:54-134:11:39), or the Papaya Nunatuk, but could also be several of the peaks along the BC/Alaska border.

If you can figure it out and tell me the reason why, I'd be able to figure out if I was correct in designating Peak Dg20 as the line parent for Peak Dg22 in the northern Purcells (Peak Dg19 being the other candidate), but feel free to have a look at that one as well.


Comments

#1449 - 2010.06.15 Robin Tivy - Definition of Line Parent
I assume you've read Definition of line Parent. In the vast majority of cases, there is only one candidate for "line parent", and everybody would come up with the same answer. But I've seen a few rare cases where you can't really tell which peak to call the line parent. For example if there are two peaks side by side, such that there isn't a clear "first peak you come to", then either could be called the line parent.

In these cases, we don't really care. Unlike "Prominence" and "key saddle", the concept of line parent is not as universally defined. Its main purpose is to "prove" that there really is higher ground beyond the key saddle. Many prominence databases in other parts of the world don't specify Line parent at all, they only specify prominence, and key saddle. (Some don't even specify the key saddle, they only give the prominence, and it is up to us to wonder if it is truely correct).

Which line parent you cite depends on what peaks are actually in the database. Normally, the peaks have been put into the database a whole area at a time, such that everything we are going to document as a "peak" is already there. However, in lots of cases when one is filling in various low prominence peaks in an area, I find that the similarly low promience parent is also not in the database. This forces me to put in the missing peaks and then go back and fix the prominences.

In some cases, we don't put in the whole chain of peaks, but instead just "skip" to a higher prominence peak which is already in the database Definition of line Parent.

The usefulness of documenting the "line parent" is to allow the mountains to be linked together in a hierarchy. The concept of "line parent" itself is not necessary for the concept of prominence, and other prominence websites don't necessarily use the term. See Wikipedia under "Topographic Prominence", (which was written by people other than myself).

Filling in the line parent gets tricky if the peak you would like to use as line parent is not yet in the database. If the "parent' is less prominence than the peak in question, it is sometimes OK to just skip over that peak, and go for the first one that is in the database.