Talk:Tag:natural=lava

Bad tag choice

natural is a key to describe a geographical feature, "lava" is not a geographical feature but a lava field is. This tag is chosen badly, I suggest to use natural=lava_field instead, so that the tag corresponds to the feature that should be tagged. --Dieterdreist (talk) 15:26, 26 February 2014 (UTC)

Agreed RicoZ (talk) 23:52, 26 February 2014 (UTC)

Why restriction to lava fields close to vulcanos?

I would not restrict the usage explicitly to lava fields close to vulcanos. There is no need to do this. Either there aren't any lava fields far from vulcanos (than you don't have to restrict the usage of the tag) or if they are, why not tag them with the same generic lava field tag? You can always determine from the database whether there is a vulcano nearby or not. -- Dieterdreist (talk) 15:26, 26 February 2014 (UTC)

The definition was never proposed or publicly discussed or voted upon

The tag definition of this tag seems to have been created unilaterally by one user bypassing the proposal process and the tagging mailing list. As the definition seems disputed and there is no proposal page I decided to move the current disputed definition here for reference and to remove it from the tag definition page in order to avoid the impression that this definition is generally agreed. --Dieterdreist (talk) 15:26, 26 February 2014 (UTC)

previous (unilateral) definition

A lava field is an area covered with cold lava from a previous volcano eruption. Plants have not yet started to grow on. These areas should be tagged as natural=lava.
Description: Lava field close to vulcano.

Lava tube as better name for a lava tunnel

Lava tunnels are more frequently known as lava tubes - https://en.wikipedia.org/wiki/Lava_tube . RicoZ (talk) 23:47, 26 February 2014 (UTC)

New proposal

Preparing a proposal:

• natural=lava_field — area — lava covered areas that are no longer flowing. Could be rocky, gravel or lava ash.
• natural=lava — area — hot, at least partially fluid lava areas.
• natural=lava_channel — way — lava flowing in a defined direction, wider streams could be delimited with natural=lava
• natural=lava_tube — way — naturally formed lava tunnel, may be active or extinct, https://en.wikipedia.org/wiki/Lava_tube

Other volcanic features:

• natural=volcano — already approved elsewhere
• crater rim - depending on shape either of
  • natural=cliff
  • natural=ridge
• natural=volcano_vent — node, area — active, maybe also inactive vents
• natural=fumarole — node, area —
• natural=geysir — node, area — the actual geysir went(s), the water pool around should be mapped with natural=water

other attributes that would be good to have defined, those are quite complex and help would be appreciated

• consistence - A'a, Pahoehoe
• temperature near surface, temperature at other interesting depths, radiated heat, date of measurement
• state extinct/active
• start of activity, end of activity - multivalued

See also:

• natural=volcano - other apsects of volcanos
• Proposed features/Hot Spring - desperately needs fresh input

RicoZ (talk) 11:51, 1 March 2014 (UTC)

One important thing to consider is having as few top tag values as possible and that they are easy(ish) for non-specialists and non-native English speakers to understand ... and still map for folks who don't care about fine distinctions. For example, we only use waterway=river/stream to map everything from the Amazon to a small desert wadi and then add additional specialist values. With that in mind, I suggest using the geological=* for specialist and precise values. (I am geophysicist by background, though my knowledge is old). Here is how I currently experimentally map the items under discussion. I prefix everything volcanic with "volcanic_" for clarity:

Lava fields

natural=bare_rock ("rock" being used in the broad sense of a consolidated (solid) or unconsolidated (granular) layer)

geological=* with =volcanic_lava_field or more specific tagging for solidified molten rock, pyroclastic mud flows etc

Lava field features

geological=volcanic_lava_channel — way — lava flowing in a defined direction

geological=volcanic_lava_tube — way — naturally formed lava tunnel, may be active or extinct, https://en.wikipedia.org/wiki/Lava_tube

etc

Crater rims

natural=cliff or natural=ridge and

geological=volcanic_caldera_rim

Volcanic vents (a volcano can often be a complex and have multiple vents)

geological=volcanic_vent

Fumaroles

geological=volcanic_fumarole

Geysers

natural=spring or or natural=hot_spring (proposed) (I mildly support the latter)

geological=volcanic_geyser (I notice that the Iceland geyser is "Geysir" but the common English spelling is geyser.

MikeCollinson (talk) 11:32, 6 March 2014 (UTC)

I think that makes a lot of sense - but how would we map lava tubes, flowing lava and hot lava pools in this framework? Also, lava fields are not always rocky, could be gravel or something similar.

How about using natural=ridge for volcano rims where the have more the appearance of a ridge?

I would also not complain if spring and hot_spring could be unified using this method, could it be

natural=spring

geological=*=volcanic_hot_spring OR geothermic_hot_spring ??

I am not sure if it is possible to classify all hot springs this way and another issue is that in some cases the mapper may have a hard time to find out which one is correct.

RicoZ (talk) 12:34, 6 March 2014 (UTC)

Thanks for your comments Rico, I have amended my proposal above.

lava tubes etc: I would do exactly as you propose, but use geological=*= not natural=*=

lava fields are not always rocky: Good point, I wondered if that would come up! My doctrine is to keep the number of choices for non-specialists as low as possible. It is also very difficult to distinguish between:

• lava flows - solidified molten rock, and
• pyroclastic deposits - the granular stuff that gets blasted out into the are and then lands, and then gets moved by water: (mud, ash, brechia, lava bombs)

on Bing imagery, which I suspect will be the main mapping tool for some years to come. ... So I'd would treat volcanic ash as an unconsolidated rock. Again, the geological=* can be used by those that want and can do more detail.

Ridges. Yes agree..

Hot springs. Yes agree with your point. Someone points out that the distinction between hot and cold is important in human, rather than purely classificatory, terms because hot springs are normal an attraction. So if it makes things nice and easy as well, I support the new tag.

MikeCollinson (talk) 10:17, 16 March 2014 (UTC)

Crater

I also miss a label to define volcanic craters http://en.wikipedia.org/wiki/Volcanic_crater

• natural=crater

Javiersanp (talk) 08:48, 2 March 2014 (UTC)

I think mapping them as natural=cliff|ridge is the way to go. Not sure if there should be an additional tag such as volcanic=yes. Also ridges aren't rendered yet - and before they can be rendered properly I think their definition needs to be refined because ridge is a very generic term. We do have natural=crater but it has never been defined and in the desert of Nevada it has been used almost a hundred times to map atomic bomb explosion craters. RicoZ (talk) 12:07, 2 March 2014 (UTC)

Agreed. See note above MikeCollinson (talk) 11:34, 6 March 2014 (UTC)

New proposal for volcanic features

.. here: http://wiki.openstreetmap.org/wiki/Proposed_features/Volcanic_features RicoZ (talk) 22:46, 30 March 2015 (UTC)