The Base Chakra is located at the perineum, between the genitals and the anus. It is the base of the body and the entry point for kundalini energies and the Lower Self. The instincts that are a part of this chakra are to do with physical survival, safety and security. Any issues to do with fear of security, safety or survival which could be financial or to do with strength, confidence, status or power are related to the unbalanced functioning of this chakra. If the Base Chakra was in total harmony with no emotional issues impeding its function, the Lower Self would operate through it. The Lower Self naturally has no fear of security, safety or survival as it is intimately connected with Mother Earth herself. In fact the Lower Self is Mother Earth and she nurtures all of her beings. You would be nurtured by her and she would take care of your security, safety and survival perfectly.
Only when the Base Chakra is functioning properly can the kundalini flow and the Lower Self nurture your being. The Higher Self will not incarnate into a body that is not nurtured by the Lower Self. If there is any fear about physical survival, safety and security the Higher Self will not descend into the body. The Base Chakra is intimately tied with the Crown Chakra as the Crown will not open without the Base first activating kundalini to rush through the body and out the top of the head.
The Base Chakra is the most physical of all the chakras and is the gateway to the lowest and densest dimensions of material. The male sexual organs are a part of this chakra and so his sexuality is very physical. In the physical body the Base Chakra relates to the hips, legs, lower back and male sexual organs.