The Virginia General Assembly today elected two Northen Virginia lawyers to six-year terms as juvenile and domestic relations court judges and selected the state's fifth black judge.

Thomas A. Fortkort, 43, a Vienna trial lawyer, was named to a new Fairfax County judgeship and Joseph L. Peters, 53, an Alexandria substitute judge for the past 10 years, was named to a judgeship there. Peters will replace Judge Irene B. Pancoast, 69, who is retiring Dec. 31.

The Assembly also approved the nomination of Norflok Vice Mayor Joseph A. Jordan Jr. to become a general district judge there. Jordan, a black lawyer who will give up his seat on the Norfolk City County to accept the judgeship, was opposed by the local bar association, but supported by his city's lelgislative delegation for the position.

Only one of the state's five black judges has been elected by the Assembly with support of local bar association.

The Assembly also named Judge William L. Winston, chief judge of the Arlington Circuit Court, to a four-year term as a member of the Judicial Inquiry and Review Commission, an organization that is charged with investigating the complaints about the state's judges.