If you wish to allocate certain submissions to specific markers, access the submission area, and click on the cog in the top right and select edit settings.
Under the Grade heading, you should see 'Use marking allocation', turn that on and save and display
Once that it is enabled, when you view all submissions, you can tick and select all submissions that you want to allocate to a specific marker
At the bottom of the page you will see a drop down menu titled 'With selected', select allocated marker from the drop down.
This will then list the lecturers on the module, select someone and click Save changes
You can now see the marker field showing the markers name and in the Marker filter, you can select who the marker is, and it will only show their submissions