d04f9e2c_r__The_Last_Airbender_resource__Aang_s_experience
[Chakra] Earth Chakra [Deals with] Survival [Blocked by] Fear [Location] Base of the spine [Aang's experience] 
Aang went into meditation and saw his fears laid out before him, including the Blue Spirit charging at him with dual swords, Katara being dragged underground by General Fong, Sozin's Comet arriving, and even himself in the Avatar State destroying his surroundings. Finally, he saw himself surrounded by fire, sitting before a man who appeared to be Fire Lord Ozai. After clearing his thoughts, the images disappeared and Aang breathed a sigh of relief as he came out of meditation. Guru Pathik congratulated him and announced that the first chakra had been opened.
Chakras - Avatar Wiki, the Avatar: The Last Airbender resource
Aang's experience