Oil-n-Water Quads: Another Parity Sudoku

Today's Puzzle:

Continuing with Blobz' lovely series based on Oil and Water never mixing. An interesting twist on this ruleset with cages that have no totals this time!

Link to Play Along:

Oil-n-Water Quads by Blobz http://tinyurl.com/SudokuSleuthOilNWaterQuads

Rules:

Normal sudoku rules apply.

Digits in circles must appear in the surrounding 2x2 area.

Digits in cages do not repeat.

Each cage is either full of "oil" (even digits), full of "water" (odd digits), or a mix of both. In all cases, each "row" within a cage is of just one type (oil or water). Oil floats on water, so even digits will always be in rows above odd digits in mixed cages.