Below is a guide on all of the collectibles you can find during the Halo Infinite mission called Excavation Site.
Spartan Audio Log #1
This log is located near a crashed transport truck down the road northwest of the Excavation Site.
Spartan Core #1
This core is located on a ledge overlooking the Excavation Site on the southwestern side.
Spartan Core #2
This core is located on the rafters in a small garage on the southeastern side of the Excavation Site.
Banished Audio Log #1
This log is located in the mining laser opposite of the laser controls.
UNSC Audio Log #1
This log is located in the mining laser at the end of the hallway west of the mining controls.
Mjolnir Armory – Banished Nameplate
This armory can be found on the southwestern side of the Excavation Site behind a metal barricade along a cliff.