Yes you can,
Joomla archive article uses a separate layout in com_content
component.
If you're planning to create a custom styles for archive articles you just need to do template override for com_content
.
In Joomla articles are managing with a component called com_content
.
you have to do a copy of components/com_content/views/archive/
files to your template folder. templates/your_templates/html/com_content/views/archive/
This way you can create custom styles for the archive articles. Also Please consider an update for your Joomla Version 1.5 is already dead.
Hope its helps..