Resource Blocks come in two varieties, Parcels and Crates.
Resource Crates are crafted by combining 9 of any of the following in a crafting grid:
There is an additional form of Crate that is not created via crafting, the Emerald Crate. This block is only obtained from an active Outpost Center, and, when harvested, will transform into a single Emerald.
Parcels are created by combining 9 Crates of the same type of material in a crafting grid. Both Parcels and Crates are used to build Buildings
Any form of Log will suffice for making Wood Crates.
You can craft them back into Crates, as well...