Cremation and Burial At Sea?

Yes, cremation is allowed and has been for almost four decades. Here are some resources from the United States Catholic Conference of Bishops (USCCB) that can be helpful for this question: [CLICK HERE].

In the Order for Christian Funeral, paragraph 413 and 417 it says:

Althought cremation is now permitted by the Church, it does not enjoy the same value as burial of the body. The Church clearly prefers and urges that the body of the deceased be present for the funeral rites.

The cremated remains shouldbe buried in a grave, entombed in a mausoleum or columbarium. The practice of scattering cremated remains on the sea, from the air, or on the ground, or keeping cremated remains in the home of a relative or firend of the deceased are not the reverent disposition that the Church requires. Whenever possible, appropriate means for recording with dignity the memory of the deceased should be adopted, such as a plaque or stone which records the name of the deceased.

The USCCB also has a booklet, Reflection on the Body, Cremation, and Catholic Funeral Rites, which says that cremated remains be treated with the same reverence and respect as a body:

The Church clearly prefers and urges that the body of the deceased be present for its funeral rites, since the presence of the human body better expressed the values that the Church affirms in its rites. This preference is reflected in the Order of Christian Funerals, which contains provision for the cremation of the body of the deceased following the Final Commendation that concludes the liturgy and before the Rite of Committal.