The Slano Blato Landslide ( sl, plaz Slano blato), or the Salt Mud Slide, is a periodic
landslide
Landslides, also known as landslips, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, deep-seated grade (slope), slope failures, mudflows, and debris flows. Landslides occur in a variety of ...
in
Slovenia that is triggered approximately once a century.
[Kovač, Mirko, & Marko Kočevar. 2001. Plaz Slano Blato nad Lokavcem pri Ajdovščini. ''UJMA'' 14–15: 122–129.]
(with photos, maps)
Although around 8,000 active landslides are present in Slovenia, the Slano Blato Landslide stands out as one of the most serious in terms of the damage it has caused.
[Komac, Blaž & Matija Zorn. ''Pobočni procesi in človek''. Ljubljana: Založba ZRC.]
The landslide is located on the southern edge of the
Trnovo Plateau of the
Dinaric Alps, below
Mount Čaven and Little Mountain () next to the Platna mountain pasture. It is moving along Grajšček Creek (which also originates in the landslide itself) toward the settlement of
Lokavec near
Ajdovščina.
[ It is long and wide, covering approximately between the elevations of .][ Its maximum flow rate was recorded at /day.][
]
Name
The name of the landslide area was recorded as ''Blatna'' ('muddy') in 1881.[ The origin of the designation 'salt(y)' (Slovene ''slan'') is uncertain. A local folk belief states that the high cleanup cost of the landslide resulted in an exorbitant cost (cf. Slovene ''zasoliti'' 'to over-salt'; metaphorically, 'to charge excessively'). However, the landslide bore the designation 'salt(y)' before any cleanup efforts were ever made.][
Other locals state that sheep used to wander down to the area from nearby pastures, where they would lick the mud as a natural ]salt lick
A mineral lick (also known as a salt lick) is a place where animals can go to lick essential mineral nutrients from a deposit of salts and other minerals. Mineral licks can be naturally occurring or artificial (such as blocks of salt that farm ...
. This basis for the name's origin is supported by the fact that chemical analysis of the water at the landslide has shown it to have a very high mineral content, including sodium sulfate
Sodium sulfate (also known as sodium sulphate or sulfate of soda) is the inorganic compound with formula Na2SO4 as well as several related hydrates. All forms are white solids that are highly soluble in water. With an annual production of 6 milli ...
, also known as Glauber's salt.[Benko, Igor. 2011. Zgodovinski pregled intervencij na plazu Slano blato. Paper presented at the conference Šukljetovi dnevi, Ajdovščina, 30 September 2011.]
(with photos, map)
History and activity
Oral tradition regarding the landslide goes back four centuries, connecting it to the construction of a small church dedicated to Saint Urban
Pope Urban I (175?–230) ( la, Urbanus I) was the bishop of Rome from 222 to 23 May 230.Kirsch, Johann Peter (1912). "Pope Urban I" in ''The Catholic Encyclopedia''. Vol. 15. New York: Robert Appleton Company. He was born in Rome and succeeded ...
on the slope of Mount Čaven above Lokavec and below the landslide. Saint Urban was invoked as a protector against natural disasters, and particularly with regard to a lake that people believed was hidden inside Mount Čaven that threatened to flood the valley.[
A 1789 source by Belsazar Hacquet mentioned the landslide, describing its debris flow in 1786.][ It was described again in an 1887 report that discussed the landslide event of 20 October 1885, in which 30 m of the road from Ajdovščina to Gorizia was destroyed.][ Cleanup efforts and landslide mitigation measures were carried out by Austrian authorities in 1903.][Medvešček, Peter. 1904. ''Opis Sv. Križa''. Gorica.]
In November 2000, heavy rain and warm weather triggered the Slano Blato Landslide, which buried about of grassland and forest.[ A secondary flow was triggered in September 2001.][ The landslide stopped moving after this and is currently considered stable.][
]
References
{{Reflist
External links
Platna Pasture at Geopedia, showing the adjacent (unlabeled) Slano Blato Landslide
Landslides in Europe
Natural disasters in Slovenia
Dinaric Alps
Geology of Slovenia
2000 in Slovenia
2000 disasters in Slovenia