<informationTable xmlns="http://www.sec.gov/edgar/document/thirteenf/informationtable" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
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       <nameOfIssuer>AT&amp;T INC</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>00206R102</cusip>
       <value>491</value>
       <shrsOrPrnAmt>
           <sshPrnamt>12089</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>12089</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>ALLSTATE CORP</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>020002101</cusip>
       <value>270</value>
       <shrsOrPrnAmt>
           <sshPrnamt>3897</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>3897</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>CIGNA CORP</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>125509109</cusip>
       <value>572</value>
       <shrsOrPrnAmt>
           <sshPrnamt>4391</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>4391</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
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   <infoTable>
       <nameOfIssuer>CHEVRON</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>166764100</cusip>
       <value>315</value>
       <shrsOrPrnAmt>
           <sshPrnamt>3063</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>3063</Sole>
           <Shared>0</Shared>
           <None>0</None>
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   <infoTable>
       <nameOfIssuer>CISCO SYSTEMS INC</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>17275R102</cusip>
       <value>318</value>
       <shrsOrPrnAmt>
           <sshPrnamt>10010</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
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       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>10010</Sole>
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           <None>0</None>
       </votingAuthority>
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   <infoTable>
       <nameOfIssuer>CONCHO RESOURCES</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>20605P101</cusip>
       <value>393</value>
       <shrsOrPrnAmt>
           <sshPrnamt>2860</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>2860</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>CONTINENTAL RESOURCES</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>212015101</cusip>
       <value>447</value>
       <shrsOrPrnAmt>
           <sshPrnamt>8600</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>8600</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>DIAMONDBACK ENERGY INC</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>25278X109</cusip>
       <value>309</value>
       <shrsOrPrnAmt>
           <sshPrnamt>3200</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>3200</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>EOG RESOURCES INC</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>26875P101</cusip>
       <value>391</value>
       <shrsOrPrnAmt>
           <sshPrnamt>4040</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>4040</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>EXXON MOBIL CORP</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>30231G102</cusip>
       <value>659</value>
       <shrsOrPrnAmt>
           <sshPrnamt>7545</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>7545</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>GENERAL ELECTRIC</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>369604103</cusip>
       <value>565</value>
       <shrsOrPrnAmt>
           <sshPrnamt>19085</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>19085</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>GENESIS ENERGY</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>371927104</cusip>
       <value>11391</value>
       <shrsOrPrnAmt>
           <sshPrnamt>300000</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>300000</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>ISHARES</nameOfIssuer>
       <titleOfClass>ETF / CLOSED EN</titleOfClass>
       <cusip>464287226</cusip>
       <value>3495</value>
       <shrsOrPrnAmt>
           <sshPrnamt>31089</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>31089</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>ISHARES</nameOfIssuer>
       <titleOfClass>ETF / CLOSED EN</titleOfClass>
       <cusip>464287226</cusip>
       <value>98</value>
       <shrsOrPrnAmt>
           <sshPrnamt>871</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <votingAuthority>
           <Sole>871</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>ISHARES</nameOfIssuer>
       <titleOfClass>ETF / CLOSED EN</titleOfClass>
       <cusip>464287465</cusip>
       <value>3894</value>
       <shrsOrPrnAmt>
           <sshPrnamt>65860</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>65860</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>ISHARES</nameOfIssuer>
       <titleOfClass>ETF / CLOSED EN</titleOfClass>
       <cusip>464287465</cusip>
       <value>236</value>
       <shrsOrPrnAmt>
           <sshPrnamt>3992</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <votingAuthority>
           <Sole>3992</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>ISHARES</nameOfIssuer>
       <titleOfClass>ETF / CLOSED EN</titleOfClass>
       <cusip>464287630</cusip>
       <value>3208</value>
       <shrsOrPrnAmt>
           <sshPrnamt>30624</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>30624</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>ISHARES</nameOfIssuer>
       <titleOfClass>ETF / CLOSED EN</titleOfClass>
       <cusip>464287630</cusip>
       <value>293</value>
       <shrsOrPrnAmt>
           <sshPrnamt>2797</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <votingAuthority>
           <Sole>2797</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>KIMBERLY CLARK CORP</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>494368103</cusip>
       <value>535</value>
       <shrsOrPrnAmt>
           <sshPrnamt>4244</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
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       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>4244</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>OCCIDENTAL PETROLEUM</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>674599105</cusip>
       <value>370</value>
       <shrsOrPrnAmt>
           <sshPrnamt>5070</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>5070</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>PIONEER NATURAL RESOURCES</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>723787107</cusip>
       <value>401</value>
       <shrsOrPrnAmt>
           <sshPrnamt>2160</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>2160</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>POWERSHARES</nameOfIssuer>
       <titleOfClass>ETF / CLOSED EN</titleOfClass>
       <cusip>73935X583</cusip>
       <value>5631</value>
       <shrsOrPrnAmt>
           <sshPrnamt>60155</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>60155</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>POWERSHARES</nameOfIssuer>
       <titleOfClass>ETF / CLOSED EN</titleOfClass>
       <cusip>73935X583</cusip>
       <value>634</value>
       <shrsOrPrnAmt>
           <sshPrnamt>6775</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>OTR</investmentDiscretion>
       <votingAuthority>
           <Sole>6775</Sole>
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           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>POWERSHARES</nameOfIssuer>
       <titleOfClass>ETF / CLOSED EN</titleOfClass>
       <cusip>73936Q769</cusip>
       <value>385</value>
       <shrsOrPrnAmt>
           <sshPrnamt>16575</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>16575</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>RSP PERMIAN INC</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>74978Q105</cusip>
       <value>337</value>
       <shrsOrPrnAmt>
           <sshPrnamt>8700</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>8700</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>RICE ENERGY INCORPORATED</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>762760106</cusip>
       <value>206</value>
       <shrsOrPrnAmt>
           <sshPrnamt>7905</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>7905</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>SPDR</nameOfIssuer>
       <titleOfClass>ETF / CLOSED EN</titleOfClass>
       <cusip>78462F103</cusip>
       <value>528</value>
       <shrsOrPrnAmt>
           <sshPrnamt>2443</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>2443</Sole>
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           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>SABRA</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>78573L106</cusip>
       <value>446</value>
       <shrsOrPrnAmt>
           <sshPrnamt>17694</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>17694</Sole>
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           <None>0</None>
       </votingAuthority>
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   <infoTable>
       <nameOfIssuer>TEXAS CAPITAL BANCSHARES</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>88224Q107</cusip>
       <value>1098</value>
       <shrsOrPrnAmt>
           <sshPrnamt>20000</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>20000</Sole>
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           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>VANGUARD ADMIRAL FUNDS INC</nameOfIssuer>
       <titleOfClass>ETF / CLOSED EN</titleOfClass>
       <cusip>921932885</cusip>
       <value>4478</value>
       <shrsOrPrnAmt>
           <sshPrnamt>42830</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>42830</Sole>
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           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>VANGUARD ADMIRAL FUNDS INC</nameOfIssuer>
       <titleOfClass>ETF / CLOSED EN</titleOfClass>
       <cusip>921932885</cusip>
       <value>395</value>
       <shrsOrPrnAmt>
           <sshPrnamt>3773</sshPrnamt>
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       <investmentDiscretion>OTR</investmentDiscretion>
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           <Sole>3773</Sole>
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           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>WAL-MART STORES INC</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>931142103</cusip>
       <value>250</value>
       <shrsOrPrnAmt>
           <sshPrnamt>3473</sshPrnamt>
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       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>3473</Sole>
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           <None>0</None>
       </votingAuthority>
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   <infoTable>
       <nameOfIssuer>WELLS FARGO &amp; CO</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>949746101</cusip>
       <value>348</value>
       <shrsOrPrnAmt>
           <sshPrnamt>7870</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>7870</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
   <infoTable>
       <nameOfIssuer>EATON CORP PLC</nameOfIssuer>
       <titleOfClass>COMMON STOCK</titleOfClass>
       <cusip>G29183103</cusip>
       <value>697</value>
       <shrsOrPrnAmt>
           <sshPrnamt>10609</sshPrnamt>
           <sshPrnamtType>SH</sshPrnamtType>
       </shrsOrPrnAmt>
       <investmentDiscretion>SOLE</investmentDiscretion>
       <votingAuthority>
           <Sole>10609</Sole>
           <Shared>0</Shared>
           <None>0</None>
       </votingAuthority>
   </infoTable>
</informationTable>
