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   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;&lt;b&gt;2. Acquisitions and Dispositions&lt;/b&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&lt;i&gt;Onshore Acquisition &amp;#8212; &lt;/i&gt;On December&amp;#160;31, 2009, Mariner acquired the reorganized subsidiaries and
   operations of Edge Petroleum Corporation (&amp;#8220;Edge&amp;#8221;). The assets acquired consist primarily of (i)
   estimated proved reserves, (ii)&amp;#160;undeveloped oil and gas property, primarily in Texas and New
   Mexico, (iii)&amp;#160;exploration assets in the form of seismic data, and (iv)&amp;#160;certain tax attributes of
   the acquired subsidiaries. The effective date of the acquisition was June&amp;#160;30, 2009 and the purchase
   price was $260.0&amp;#160;million, less adjustments which resulted in a net purchase price as of December
   31, 2009 of approximately $213.6&amp;#160;million, subject to final adjustments. Mariner financed the net
   purchase price by borrowing under its secured revolving credit facility.
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   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&lt;i&gt;Pro Forma Financial Information: &lt;/i&gt;The unaudited pro forma information set forth below gives
   effect to the acquisition of the reorganized Edge subsidiaries as if it had been consummated as of
   the beginning of the applicable period. The unaudited pro forma information has been derived from
   the historical Consolidated Financial Statements of the Company and of Edge. The unaudited pro
   forma information is for illustrative purposes only. The financial results may have been different
   had each of the acquired Edge subsidiaries been an independent company and had the companies always
   been combined. No reliance should be placed on the pro forma financial information as being
   indicative of the historical results that would have been achieved had the acquisition occurred in
   the past or the future financial results that the Company will achieve after the acquisition.
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       &lt;td nowrap="nowrap" align="center" colspan="3" style="border-bottom: 0px solid #000000"&gt;&lt;b&gt;For the Three Months&lt;/b&gt;&lt;/td&gt;
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       &lt;td nowrap="nowrap" align="center" colspan="7" style="border-bottom: 1px solid #000000"&gt;&lt;b&gt;Ended June 30, 2009&lt;/b&gt;&lt;/td&gt;
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       &lt;td&gt;&amp;#160;&lt;/td&gt;
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       &lt;td nowrap="nowrap" align="center" colspan="7"&gt;&lt;b&gt;(In thousands, except &lt;br /&gt;
   per share amounts)&lt;/b&gt;&lt;/td&gt;
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Pro Forma:
   &lt;/div&gt;&lt;/td&gt;
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       &lt;td align="right"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;244,123&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
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       &lt;td align="right"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;511,944&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Net income (loss)&amp;#160;available to common stockholders
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;8,238&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="right"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;(491,113&lt;/td&gt;
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Basic income (loss)&amp;#160;per share
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;0.09&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="right"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;(5.44&lt;/td&gt;
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Diluted income (loss)&amp;#160;per share
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       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;0.09&lt;/td&gt;
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       &lt;td align="right"&gt;(5.44&lt;/td&gt;
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      <ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 141
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Emerging Issues Task Force (EITF)
 -Number 88-16

Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 141R
 -Paragraph 67-73

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 -Name Statement of Financial Accounting Standard (FAS)
 -Number 141R
 -Paragraph F4
 -Subparagraph e
 -Appendix F

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