Small Aircraft; High Wing; 1 Eng; Fixed Gear
Air Traffic Control Developmental
Situational Awareness; Training / Qualification
ATC Issue All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Issued New Clearance
Airspace Structure; Chart Or Publication; Human Factors; Procedure
Aircraft X called airborne off of ZZZ for his clearance to ZZZ1. I handed the strip to the Radar Controller; who radar identified and cleared the aircraft as filed and to maintain his assigned altitude of 7000 feet. I updated the aircraft's route in the computer. None of us pulled up the MIA (Minimum IFR Altitude) chart. The altitude did not set off any alarm bells in my head. As we routinely see aircraft in this vicinity at 7000 feet; though most often on an airway. A few minutes later; after the aircraft was level; I noticed the MSAW (Minimum Safe Altitude Warning) alert flashing for a 7700 foot MIA. I physically pointed to the alerting aircraft on the scope. The Radar Controller turned the aircraft 15 degrees right for terrain; then assigned a heading of 090. The MSAW alert stopped shortly thereafter and the Radar Controller re cleared the aircraft on course. I could not determine from where I was sitting if the aircraft was in; on the boundary; or just outside the boundary of the MIA. At some point; the Radar Controller said he didn't think the 7700 foot MIA went so far south. I too did not think the higher MIA went as far south as it did. This is an unfortunate reminder to read every strip and not become complacent with what looks familiar. A subtle difference in course can have huge implications. I also need to remind myself that even though I am learning a sector; it is okay to look up information again and again; even if my trainers do not seem concerned. It would have been helpful if the MSAW alert has gone off sooner.
ZSE Center Controller reported they cleared an aircraft to an altitude below the Minimum Vectoring Altitude.