Is sending vulgar material over the internet child abuse?

Our daughter is 14 years old and I found sexually explicit material on her computer. When I confronted her about it she said it was from an older boy she met at a party. She thinks he is 19 but isn’t sure. She claims she has not seen him since the party and has only communicated with him through the computer, so he hasn’t physically done anything to her. She admits she lied to him about her age. I want to know whether sending this kind of sexual material to a minor over the internet constitutes child abuse if the person sending it is an adult? Should I report this to Los Angeles County Dept. of Children and Family Services? Will they be able to find this person if my daughter doesn’t know his last name or where he lives? Are there criminal charges I can file?