This definition appears somewhat frequently
and is found in the following Acronym Finder categories:
- Science, medicine, engineering, etc.
See other definitions of EI
Samples in periodicals archive:
However, data from the Viirelaid, Paatsalu and Suigu (S-3) core sections suggest that the gap, and accordingly the maximum shallowing of the sea, is younger and lies in the Ireviken Event interval, in the upper C.
The Ireviken Event interval recognized in more complete successions in Estonia and Gotland (Jeppsson & Mannik 1993) is almost entirely missing in the Paatsalu section (only datum points 1 and 8 can be identified).
I will assume that the suffix -ung not only turns the verb into a noun but also makes the event interval accessible to syntactic modification.