Reuters writes the story as follows:
An entire California diocese of the U.S. Episcopal Church voted to secede on Saturday in a historic split following years of disagreement over the church’s expanding support for gay and women’s rights
You can read it all here.
But the fact is that dioceses can’t leave the Church because it is the Church which creates dioceses, and not dioceses which create the Church. What happened today is that somewhere in the vicinity of 7,500 members decided to leave the 2.2 million member Episcopal Church. That they chose to make their decision collectively does not alter the fact that they leave as individuals. At least five congregations remain, and it will be up to the Church to reconstitute the diocese.
Next the delegates will decide whether to align themselves with the tiny province of the Southern Cone, which is based in Argentina. The Southern Cone has previously laid claim to the Diocese of Recife in Brazil, but its claim is not recognized by the Anglican Communion,