Heavy and synthetic grades steady

The Canadian heavy crude oil differential compared with U.S. oil futures was unmoved on Friday from the previous day's settle:

* Western Canada Select (WCS) heavy blend crude for May delivery in Hardisty, Alberta, last traded at $9.25 a barrel below WTI crude futures , holding steady from the previous day, according to Net Energy Exchange.

* Market activity is slowing as the monthly Canadian crude trading window, which runs from the first of each month until the day before pipeline nominations are due, nears its close. The final trading day of this cycle is Monday.

* Light synthetic crude from the oil sands for May delivery did not trade on Friday. On Thursday it settled at 85 cents per barrel over WTI.

* U.S. crude settled at $63.89 a barrel, up 31 cents on the day, as involuntary supply cuts from Venezuela and Iran plus conflict in Libya supported perceptions of a tightening crude market, while upbeat Chinese economic data eased concerns about waning crude demand.

(Reporting by Nia Williams in Calgary, Alberta; Editing by Tom Brown)