<?xml version="1.0" encoding="utf-8"?>
<schema xmlns="http://www.w3.org/2001/XMLSchema" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ec="http://www.sec.gov/xbrl/fr/ec/2007-04-30" targetNamespace="http://www.sec.gov/xbrl/fr/ec/2007-04-30" elementFormDefault="qualified" attributeFormDefault="unqualified">
  <annotation>
    <appinfo>
      <link:linkbaseRef xlink:type="simple" xlink:href="ec-2007-04-30-label.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Label Links, all" />
      <link:linkbaseRef xlink:type="simple" xlink:href="ec-2007-04-30-reference.xml" xlink:role="http://www.xbrl.org/2003/role/referenceLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Reference Links, all" />
      <link:linkbaseRef xlink:type="simple" xlink:href="ec-2007-04-30-presentation.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Presentation Links, all" />
      <link:linkbaseRef xlink:type="simple" xlink:href="ec-2007-04-30-calculation.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Calculation Links, all" />
    </appinfo>
  </annotation>
  <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <element name="AllOtherCompensation" id="ec_AllOtherCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" />
  <element name="Bonus" id="ec_Bonus" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" />
  <element name="ChangeInPensionValueNonqualifiedDeferredCompensationEarnings" id="ec_ChangeInPensionValueNonqualifiedDeferredCompensationEarnings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" />
  <element name="GrantDateFairValue" id="ec_GrantDateFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" />
  <element name="Name" id="ec_Name" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" />
  <element name="NonEquityIncentivePlanCompensation" id="ec_NonEquityIncentivePlanCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" />
  <element name="OptionAwards" id="ec_OptionAwards" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" />  
  <element name="PrincipalPosition" id="ec_PrincipalPosition" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" />
  <element name="Salary" id="ec_Salary" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" />  
  <element name="SECPrincipalPosition" id="ec_SECPrincipalPosition" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" />  
  <element name="StockAwards" id="ec_StockAwards" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" />
  <element name="SummaryCompensation" id="ec_SummaryCompensation" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" />
  <element name="Total" id="ec_Total" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" />  
  <element name="Year" id="ec_Year" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" />
  <element name="Executive" id="ec_Executive" substitutionGroup="xbrli:tuple" nillable="true">
    <complexType>
      <complexContent>
        <restriction base="anyType">
          <sequence>
            <element ref="ec:Name" minOccurs="1" />
            <element ref="ec:PrincipalPosition" minOccurs="1" />
            <element ref="ec:SECPrincipalPositions" minOccurs="0" maxOccurs="1" />
            <element ref="ec:FiscalYearCompensation" minOccurs="1" maxOccurs="unbounded" />
          </sequence>
          <attribute name="id" type="ID" use="optional" />
        </restriction>
      </complexContent>
    </complexType>
  </element>
  <element name="FiscalYearCompensation" id="ec_FiscalYearCompensation" substitutionGroup="xbrli:tuple" nillable="true">
    <complexType>
      <complexContent>
        <restriction base="anyType">
          <sequence>
            <element ref="ec:Year" minOccurs="1" />          
            <element ref="ec:Salary" minOccurs="0" />
            <element ref="ec:Bonus" minOccurs="0" />
            <element ref="ec:StockAwards" minOccurs="0" />
            <element ref="ec:OptionAwards" minOccurs="0" />
            <element ref="ec:NonEquityIncentivePlanCompensation" minOccurs="0" />
            <element ref="ec:ChangeInPensionValueNonqualifiedDeferredCompensationEarnings" minOccurs="0" />
            <element ref="ec:AllOtherCompensation" minOccurs="0" />
            <element ref="ec:Total" minOccurs="1" />
            <element ref="ec:GrantsPlanBasedAwards" minOccurs="0" />
          </sequence>
          <attribute name="id" type="ID" use="optional" />
        </restriction>
      </complexContent>
    </complexType>
  </element>  
  <element name="GrantsPlanBasedAwards" id="ec_GrantsPlanBasedAwards" substitutionGroup="xbrli:tuple" nillable="true">
    <complexType>
      <complexContent>
        <restriction base="anyType">
          <sequence>
            <element ref="ec:GrantDateFairValue" minOccurs="1" maxOccurs="unbounded" />
          </sequence>
          <attribute name="id" type="ID" use="optional" />
        </restriction>
      </complexContent>
    </complexType>
  </element>    
  <element name="SECPrincipalPositions" id="ec_SECPrincipalPositions" substitutionGroup="xbrli:tuple" nillable="true">
    <complexType>
      <complexContent>
        <restriction base="anyType">
          <sequence>
            <element ref="ec:SECPrincipalPosition" minOccurs="1" maxOccurs="unbounded" />
          </sequence>
          <attribute name="id" type="ID" use="optional" />
        </restriction>
      </complexContent>
    </complexType>
  </element>    
  <element name="Agency" id="ec_linkPart_Agency" type="string" substitutionGroup="link:part">
    <annotation>
      <documentation>Reference to specific agency publishing guidance.</documentation>
    </annotation>
  </element>
  <element name="FedCodeRegulation" id="ec_linkPart_FedCodeRegulation" type="string" substitutionGroup="link:part">
    <annotation>
      <documentation>Federal Code Regulation.</documentation>
    </annotation>
  </element>    
  <element name="Page" id="ec_linkPart_Page" type="string" substitutionGroup="link:part">
    <annotation>
      <documentation>Page number in the publication.</documentation>
    </annotation>
  </element>  
  <element name="ReleaseNo" id="ec_linkPart_ReleaseNo" type="string" substitutionGroup="link:part">
    <annotation>
      <documentation>Number of the specific release.</documentation>
    </annotation>
  </element>
</schema>