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       &lt;td&gt;&lt;b&gt;BASIS OF PRESENTATION&lt;/b&gt;&lt;/td&gt;
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       &lt;td&gt;&lt;b&gt;&lt;i&gt;Description of Operations&lt;/i&gt;&lt;/b&gt;&amp;#8212;Whiting Petroleum Corporation, a Delaware corporation, is an
   independent oil and gas company that acquires, exploits, develops and explores for crude
   oil, natural gas and natural gas liquids primarily in the Permian Basin, Rocky Mountains,
   Mid-Continent, Gulf Coast and Michigan regions of the United States. Unless otherwise
   specified or the context otherwise requires, all references in these notes to &amp;#8220;Whiting&amp;#8221; or
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       &lt;td&gt;&lt;b&gt;&lt;i&gt;Consolidated Financial Statements&lt;/i&gt;&lt;/b&gt;&amp;#8212;The unaudited consolidated financial statements include
   the accounts of Whiting Petroleum Corporation, its consolidated subsidiaries, all of which
   are wholly-owned, and Whiting&amp;#8217;s pro rata share of the accounts of Whiting USA Trust I
   pursuant to Whiting&amp;#8217;s 15.8% ownership interest. Investments in entities which give Whiting
   significant influence, but not control, over the investee are accounted for using the equity
   method. Under the equity method, investments are stated at cost plus the Company&amp;#8217;s equity
   in undistributed earnings and losses. All intercompany balances and transactions have been
   eliminated upon consolidation. These financial statements have been prepared in accordance
   with GAAP for interim financial reporting. In the opinion of management, the accompanying
   financial statements include all adjustments (consisting of normal recurring accruals and
   adjustments) necessary to present fairly, in all material respects, the Company&amp;#8217;s interim
   results. However, operating results for the periods presented are not necessarily
   indicative of the results that may be expected for the full year. Whiting&amp;#8217;s 2009 Annual
   Report on Form 10-K includes certain definitions and a summary of significant accounting
   policies and should be read in conjunction with this Form 10-Q. Except as disclosed herein,
   there have been no material changes to the information disclosed in the notes to the
   consolidated financial statements included in Whiting&amp;#8217;s 2009 Annual Report on Form 10-K.&lt;/td&gt;
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       &lt;td&gt;&lt;b&gt;&lt;i&gt;Earnings Per Share&lt;/i&gt;&lt;/b&gt;&amp;#8212;Basic earnings per common share is calculated by dividing net income
   available to common shareholders by the weighted average number of common shares outstanding
   during each period. Diluted earnings per common share is calculated by dividing adjusted
   net income available to common shareholders by the weighted average
   number of diluted common shares outstanding, which includes the effect of potentially dilutive securities.
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