I think that it would still just be an island. A peninsula is a landform surrounded by water that extends outward from the land. Imagine a green rectangle sticking out from the green oval you pictured. That rectangle would represent the peninsula. Therefore, dividing the island in half would not create any peninsulas. Hope this helps :)
I used to read word up magazine
Lava plateaus is formed by highly fluid (runny) basaltic lava during numerous successive eruptions through numerous vents without violent explosions (quiet eruptions). These eruptions are quiet because of low vicosity are of mafic lava, so that it is very fluid and contains a small amount of trapped gases.
