March 11 (Reuters) - Williams Partners LP WPZ.N :
* Shell (LON:RDSa) and nexen reach agreement on deepwater gulf project
* Says shell is 79 percent owner in the appomattox development and is the
operator; nexen is 21 percent owner
* Says will provide offshore gas gathering services to its existing transco
lateral
* Agreement with shell offshore and nexen petroleum offshore USA to provide
deepwater gas gathering services to appomattox development
* Source text for Eikon
* Further company coverage WPZ.N