Drill a Deep Hole in the Siljan Ring Granite Dome - Could Oil and Natural Gas be Found?
In the 1980s, a 7,000-meter-deep hole was drilled in Gravberg to explore the possibility of finding oil and natural gas in the granite dome of the Siljan Ring.
However, the company Dala Djupgas did not discover any oil or natural gas. The whole endeavor cost 230 million kronor, but, in return, geologists gained more knowledge about the Siljan Ring.
Siljan Ring, a Meteorite Crater
380 million years ago, a large meteorite struck what is now Dalarna, creating a 6.5-mile-wide crater. Most of the crater has eroded away today, but the impact reshaped the rock, giving rise to today's flat dome of bedrock in the center of the crater. Gravberg is located on the edge of the dome, and around the dome, there is a depression. In this depression, softer rocks such as limestone, shale, and sandstone have been preserved. In some places, these rocks have been tilted upright by the immense forces at play.
However, the company Dala Djupgas did not discover any oil or natural gas. The whole endeavor cost 230 million kronor, but, in return, geologists gained more knowledge about the Siljan Ring.
Siljan Ring, a Meteorite Crater
380 million years ago, a large meteorite struck what is now Dalarna, creating a 6.5-mile-wide crater. Most of the crater has eroded away today, but the impact reshaped the rock, giving rise to today's flat dome of bedrock in the center of the crater. Gravberg is located on the edge of the dome, and around the dome, there is a depression. In this depression, softer rocks such as limestone, shale, and sandstone have been preserved. In some places, these rocks have been tilted upright by the immense forces at play.
