University of Virginia Provost Gene D. Block will become the next chancellor of UCLA, if his appointment is approved by the University of California's Board of Regents in a special meeting Thursday, according to sources close to the search.

UC President Robert C. Dynes is expected to ask the regents to appoint Block, 58, a biologist, to fill the position left vacant by the departure last summer of Albert Carnesale, the sources said. Block has held the No. 2 post at the University of Virginia since 2001.

UCLA law professor Norman Abrams has served as acting chancellor of the campus since Carnesale stepped down and, assuming the new leader is approved, is expected to remain in the job until Block's arrival in July, the sources said. They spoke on condition of anonymity because of the sensitivity of the search process.

Block is described by those who know him as quiet and low-key, though approachable and popular with faculty and students alike. His expertise in science has not precluded him from fostering strong ties to faculty in areas such as the humanities and social sciences, and several colleagues also emphasized Block's role at the University of Virginia in helping to increase racial and gender diversity among the faculty.

"He's not afraid of complicated, difficult issues," said Gertrude Fraser, who has worked closely with Block as the university's vice provost for faculty advancement. "He's dealt with them."

That ability could serve Block in good stead as he arrives at a campus whose leadership is dealing with a number of complex, high-profile issues, including efforts to increase student diversity, a particular concern being the low number of African Americans on campus, and cost overruns at the university's long-delayed new medical centers.