Dec. 6 (Bloomberg) -- Petrominerales Ltd., a Calgary-based company that explores for and produces oil in Colombia, plunged the most on record after it announced a drop in November output, delays in Peru drilling operations and suspension of drilling at two Colombian wells.

The shares fell 16 percent to 32,800 pesos in Bogota, the lowest level since they began trading in August.

“The drilling results announced in the company’s exploration update were not positive,” Maria Adelaida Velasquez, an oil sector analyst at Interbolsa SA, Colombia’s biggest brokerage, said in a phone interview from Medellin.

November production fell 5 percent from October, Petrominerales said in a regulatory filing today. The company suspended the Socaco-1 well and is considering using the Caspio- 1 well for water disposal after concluding continued drilling “would not be economic,” the filing said.

Peru drilling also was delayed due to low river levels and adverse weather, the filing said.

--Editor: Brendan Walsh, Marie-France Han

To contact the reporter on this story: Blake Schmidt in Bogota at bschmidt16@bloomberg.net

To contact the editor responsible for this story: David Papadopoulos at papadopoulos@bloomberg.net