LOS ANGELES -- A Northern Virginia minister and private-practice counselor died on a spiritual retreat high in the Sierra Nevada, authorities said Tuesday.

The Rev. Karen Blomberg, associate pastor of Westminster Presbyterian Church in Alexandria, died Monday morning from asphyxiation due to a pulmonary embolism, or blood clot, said Leon Brune of the Inyo County coroner's office.

Ms. Blomberg, 54, was part of a 16-woman "Elderquest" excursion hosted by the nature-based spiritual group Wilderness Rites and camped at Badger Flats at the 9,000-foot level in the mountains above Independence, Calif., about 170 miles north of Los Angeles, Brune said.

One of the group began waking up other members at 6 a.m. and heard Ms. Blomberg calling out to her, Brune said. Ms. Blomberg, who had been in good health, was found lying next to her tent, sweating profusely and having chest pains.

She was transported to Southern Inyo Hospital in Lone Pine, where she was pronounced dead at 8 a.m., Brune said.

Asked if the heightened elevation could have caused Ms. Blomberg's death, Brune said "that would be rare, but I have seen that before."

According to Westminster Presbyterian Church's Web site, Ms. Blomberg worked part-time for the church and had been a member of its staff since 1990.

She earned her master's degree in divinity from Princeton Seminary in 1981 and her master's degree in theology in 1986. She also had a private counseling practice in Washington, said the site.

"We are saddened to report the sudden death" of Ms. Blomberg, the Rev. Larry R. Hayward wrote on the site.

Ms. Blomberg's survivors include her father, Kenneth Blomberg of Indianapolis, and two brothers, Bruce Blomberg of Indianapolis and Ronald Blomberg of Germany.

A memorial service is scheduled for Sunday at Westminster Presbyterian Church.