What Falling Oil Prices Are Doing To America's Ten Richest Oil Tycoons

As oil prices continue to fall, some of America's richest oil tycoons have stayed on top and continued to make money while others have seen their fortunes cut in half.

According to Wealth-X, four of the top ten oil billionaires have actually upped their net worth since oil prices started to decline.

David and Charles Koch top the list with a 7 percent increase in net worth since June, which Wealth-X attributes to the diversification of their company's investment portfolio. Elaine Marshall, who holds about 15 percent of Koch Industries saw her net worth increase by 6 percent. Richard Kinder of Kinder Morgan Partners increased his net worth the most by 23 percent.

The biggest loser among the top ten by far was Continental Resources CEO Harold Hamm, currently caught in a bitter and costly divorce battle, who lost 50 percent of his net worth since June. Sisters Milane Frantz, Randa Williams and Dannine Avara of the Duncan energy empire all saw their net worth decline by 11 percent.

Here's the full list from Wealth-X below:

1. David Koch
Net worth in June 2014: $42 billion
Current net worth: $44.9 billion
% change in net worth: 7%

2. Charles Koch
Net worth in June 2014: $42 billion
Current net worth: $44.8 billion
% change in net worth: 7%

3. George Kaiser
Net worth in June 2014: $13.3 billion
Current net worth: $13.2 billion
% change in net worth: -1%

4. Richard Kinder
Net worth in June 2014: $9.2 billion
Current net worth: $11.3 billion
% change in net worth: 23%

5. Harold Hamm
Net worth in June 2014: $18.5 billion
Current net worth: $9.3 billion
% change in net worth: -50%

6. Elaine Marshall
Net worth in June 2014: $7.8 billion
Current net worth: $8.3 billion
% change in net worth: 6%

7. Ray Hunt
Net worth in June 2014: $6 billion
Current net worth: $5.6 billion
% change in net worth: -7%

8. Milane (Duncan) Frantz
Net worth in June 2014: $6.2 billion
Current net worth: $5.5 billion
% change in net worth: -11%

9. Randa (Duncan) Williams
Net worth in June 2014: $6.2 billion
Current net worth: $5.5 billion
% change in net worth: -11%

10. Dannine (Duncan) Avara
Net worth in June 2014: $6.2 billion
Current net worth: $5.5 billion
% change in net worth: -11%