You should make sure that your oracle data base driver is successfully installed before adding the data source.

As the log shows, the oracle driver is missing. You should add it to the system as a module. Check whether the WILDFLY_HOME/modules/system/layers/base/com/oracle/ojdbc6/main folder exists. If not, you have to crate it. Copy the oracle driver (ojdbc6.jar) into this folder. Create also a module.xml in the folder with the following content:

<?xml version='1.0' encoding='UTF-8'?>

<module xmlns="urn:jboss:module:1.1" name="com.oracle.ojdbc6">

    <resources>

        <resource-root path="ojdbc6.jar"/>

    </resources>

    <dependencies>

        <module name="javax.api"/>

        <module name="javax.transaction.api"/>

    </dependencies>

</module>

In the standalone.xml under the datasource subsystem you should add the next driver definition:

<drivers>

     . . .

     <driver name="oracle" module="com.oracle.ojdbc6">

          <driver-class>oracle.jdbc.OracleDriver</driver-class>

          <xa-datasource-class>oracle.jdbc.xa.client.OracleXADataSource</xa-datasource-class>

     </driver>

</drivers>

In the datasource definítion you should refrence the oracle driver like this:

<driver>oracle</driver>

That's all.

In the log you should see somthing like this at the starting process of server:

INFO  [org.jboss.as.connector.subsystems.datasources] (ServerService Thread Pool -- 44)() WFLYJCA0004: Deploying JDBC-compliant driver class oracle.jdbc.OracleDriver (version 11.2)

INFO  [org.jboss.as.connector.deployers.jdbc] (MSC service thread 1-3)() WFLYJCA0018: Started Driver service with driver-name = oracle

Of course you may need another version of oracle driver. In this case you should use that is appropriate for you.