Aqaaid

Gadats

Q: Are 'gadats' which are commonly performed in (cape town , south africa) part of our Islamic religion and is it mentioned in the Quran. Is it a good thing? A Sunnah? Will one benefit from taking part in these 'gadats'? We also refer to these 'gadats' as 'thikrs'. Is gadats and thikr the same thing? What is the difference? What about the 3,7,40,100day (gadat) ceremonies for the deceased?