Oooook ... there's quite a bit of material on fish to tetrapod at Devonian Times - Error 404 (Not Found)!!1 as well as at http://www.origins.tv/darwin/tetrapods.htm - or anywhere that you can find anything about Jennifer Clack. Her book, Gaining Ground, has detail enough to reduce you to babbling.
When lava from the region was recently dated, the result was about 70CE - showing an accurate result.
And when the layers of ice in the Greenland ice cap were counted, the layer of ash with the chemical signature of Vesuvius matched up, too. And there's another 100,000 layers older than that one in that same core...