The lava at Holuhraun is now flowing into Jökulsá á Fjöllum glacial river. So far this has had little effect, but the lava is now flowing faster than before, at a speed of 80 to 100 meters/hour (250 to 330 feet/hour), which is about twice the speed of the flow yesterday. This was observed by scientists at 7:00 am this morning.
When lava flows over water, so-called pseudocraters may be formed. Pseudocraters are formed by steam explosions as flowing hot lava crosses over a wet surface, such as a swamp, a lake, or a pond. The explosive gases break through the lava surface in a manner similar to a phreatic eruption, and the tephra builds up crater-like forms which can appear very similar to real volcanic craters, according to Wikipedia. They are common in Iceland.
Volcanologist Þorvaldur Þórðarson told RÚV this morning that no pseudocraters had formed so far, but that might happen later. The lava could block the river, moving the riverbed further to the east. That has not happened yet, but scientists are following the events closely.
This morning, we also reported that earthquake activity in Bárðarbunga and a depression in the glacier make an eruption under the glacier more likely than before, according to geophysicist Magnús Tumi Guðmundsson.