252 million years ago, Siberia erupted, releasing enough lava to fill in a volume anywhere between one and four million cubic kilometers. Any time someone thinks "large igneous province", the Siberian Traps seem to be the first thing on his mind.
But the actual largest igneous province is the Ontong Java-Manihiki-Hikurangi Plateau in the depths of the Pacific Ocean. It erupted over 120 million years ago and released enough lava to fill in a volume anywhere between 59 and 77 million cubic kilometers.
I am working on an earth-like planet with somewhat alternate history and I want to make a volcanic eruption on land (like the Siberian Traps) with a lava output equaling to that of Ontong-Java underwater eruption.
What necessary changes must I make in my world (with emphasis on geology and geography related changes) that would allow me to make a land-based volcanic action spew as much lava as the benthic eruption of Ontong-Java (59-77 million cubic km)?