ANADARKO PETROLEUM CORP | 2013 | FY | 3

The following summarizes impairments by segment for the years ended December 31:
millions
2013
 
2012
 
2011
Oil and gas exploration and production
 
 
 
 
 
Long-lived assets held for use
 
 
 
 
 
U.S. onshore properties
$
142

 
$
259

 
$
1,063

Gulf of Mexico properties
562

 
104

 
162

Cost-method investment
11

 
13

 
91

Midstream
 
 
 
 
 
Long-lived assets held for use
79

 
13

 
458

Impairments
$
794

 
$
389

 
$
1,774

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