The first two wave types, P and S , are called body waves because they travel or propagate through the body of Earth. The latter two are called surface waves they the travel along Earth's surface and their amplitude decreases with depth into Earth.
The causes are many and can have bacterial infection, seborrheic dermatitis of the face or even a scalp, rosacea, allergies, and in very rare cases, the lice. If the itchy eyelids is brought about by seborrheic dermatitis then you may develop dry, flakey patches of skin on the eyelid.
Symptoms of eyelid inflammation. Eyelid inflammation is usually noticeable because it can irritate your eyes and possibly affect your vision. Symptoms of inflammation include: itchy eyelids. swollen eyelids. red or inflamed eyelids. a burning sensation in the eyes. oily eyelids. a feeling that something is in or on your eyes.