The National Park Service distributes photos on Thursday that shows there's more damage to the monument than initially believed.
One shows a marble brick that has been dislodged near the top of the monument, while another shows debris on the passageways and stairwells leading to the observation area.
Tipping Mar Associates of Berkeley is one of two firms with earthquake experience that are now conducting a detailed assessment of the landmark. The monument has been off-limits to the public since the 5.8-magnitude earthquake that struck on Tuesday.
There have benn seven aftershocks following the moderate earthquake.