Catastrophe Naturelle

Hi can anybody or manybodys shed some light on this phenomon !

my commune has an arrete for secheresse - i have a large crack in a stone wall of one of my properties which hasnt always been there , not exactly sure when it appeared as we were non resident for some time.Further up above the crack i have lost about 1.5 - 2 m square of stones which should have been held in place by mortars etc.

does this catastrophe arrete mean my insurance is obliged to cough up ? or do they wriggle like a snake across the sand !