Kodiak's average daily sales volume in the Bakken went up 98% to 36,100 boe/d in the fourth-quarter of 2013 from 18,200 boe/d in the fourth-quarter of 2012. Crude oil made up most of the company's sales volume at 89% in the fourth-quarter.

Average daily sales volumes increased 103% for the year to 29,200 boe/d in 2013 from 14,400 boe/d in 2012.

Kodiak Bakken Acquisitions and Drilling Operations in 2013

In 2013, Kodiak invested approximately $672 million on acquisitions net of divestitures in the Bakken. In June 2013, Kodiak Oil & Gas signed a purchase and sale agreement with Liberty Resources for 42,000 net acres in the Williston Basin for $660 million.

The acquisition included acreage prospective for the Bakken and Three Forks formations in McKenzie and Williams counties.

Read more:Kodiak Buying Bakken Assets from Liberty Resources For $660 Million

For the full year 2013, Kodiak invested ~ $1.0 billion in capital expenditures for drilling and completing new wells, including surface facilities and pipeline connections in the Bakken. In the fourth-quarter of 2013, the company completed 29 gross (21.9 net) operated wells and 40 gross (4.0 net) non-operated wells. Currently, Kodiak has 7 operated rigs in the Williston Basin.

Kodiak Bakken Reserves

Kodiak estimates the value of its proved total reserves increased from $1.9 billion in 2012 to $3.5 billion at the end of the year in 2013. That's an 81% increase.

The company's estimated proved reserves increased 77% to 167.3 million boe from 94.7 million boe in 2012. Total proved crude oil reserves are 138.2 million bbl crude oil and total natural gas reserves of 174 bcf natural gas.

Make-up of Kodiak's Proved Reserves at the end of year 2013:

• 138.2 million bbl crude oil (83%)
• 174 bcf natural gas (17%)
• 46% of 2013 proved reserves are developed and producing
• 54% of 2013 proved reserves are undeveloped

Of the 54% of proved reserves that are undeveloped, Kodiak estimates those properties are a 2.5 year drilling inventory.