The way I read it is, the water spring is fed from whatever lies under Panama. However, there are a lot of helium isotopes in the water from that spring. It is theorized that the helium isotopes come from the magna flow from the Galapagos, which gets into the water. IOW, the water is from Panama, but the magma (as thus, the helium isotopes) come from the Galapagos. Regardless, the interesting part is that no matter where that water comes from, magma can apparently spread out laterally rather than just making islands and volcanoes.
But that's just my reading, I'm probably just as confused.
[Remainder to understand my explanation: When "lava" is under earth, it's called "magma". I had to look at Wikipedia because I never remember. https://xkcd.com/903/ ]
There is a big mantle plume under the Galapagos islands https://en.wikipedia.org/wiki/Mantle_plume . Imagine a lot of magma, and some part of it escapes and goes to the volcanoes and you see it as lava.
They discovered that there is a "river" of magma that goes from the plume of magma under the Galapagos to Panama.
In Panama the magma meets some underneath water, an some of the gas disolved in the magma goes to the water. Then the water colds down, and after some time it appears in a few springs in Panama.
They realize this, because they analyzed the gases disolved in the water of the springs.
There is no water traveling from the Galapagos to Panama.
