Just for fun, here's 3d version:

reliefmap = 
  GeoGraphics[Entity["Volcano", "Bardarbunga"], 
   GeoRange -> Quantity[100, "Kilometers"], 
   GeoBackground -> GeoStyling["ReliefMap"]];

latlong = 
  GeoBoundingBox[
   GeoDisk[Entity["Volcano", "Bardarbunga"], 
    Quantity[100, "Kilometers"]]];
alt = Reverse[
   QuantityMagnitude[
    GeoElevationData[latlong, UnitSystem -> "Metric"]]];

bardabunga = 
  ListPlot3D[alt, 
   PlotStyle -> Directive[Opacity[.7], Texture[reliefmap]], 
   Mesh -> 10, MeshFunctions -> {#3 &}, 
   TextureCoordinateFunction -> ({#1, #2} &), 
   MeshStyle -> GrayLevel[.5], Lighting -> "Neutral", 
   MaxPlotPoints -> 120, Boxed -> False, Axes -> False, 
   DataRange -> Reverse[Transpose[latlong[[All, 1]]]]];

data = "results" /. Import["http://apis.is/earthquake/is", "JSON"];

data3d = Map[{"size", {"longitude", "latitude", -100 "depth"}} /. # &,
    data];
minmax = Through[{Min, Max}[data3d[[All, 1]]]];

earthquakes = {Point[#2, 
      VertexColors -> (Hue[0, #] & /@ 
         Rescale[#1, minmax, {.1, 1}])]} & @@ Transpose[data3d];

prange = bardabunga // PlotRange;

prange[[3, 1]] = Min[data3d[[All, 2, 3]]];

Show[{bardabunga, Graphics3D[{PointSize[.004], earthquakes}]}, 
 ImageSize -> 720, PlotRange -> prange, BoxRatios -> {1, 1, .7}, 
 Background -> Black]

Yes, using the techniques described above but saving image for every minute: https://vimeo.com/104637028

And how to generate the animation.

And Double-Wow!