Mark Wilson July 8th, 2013
MITZPE RAMON, ISRAEL–Our next stop on this day of exploration was 32 km southeast of Mitzpe Ramon at outcrops of the Matred Formation (Middle Eocene). The location is N 30.36899°, E 34.98655°. Look at those coordinates on Google Maps and you’ll see that they are from the peak of that black mountain on the right of the above view. The black color is from the weathering of thoroughly-silicified (infused with silica) coral-rich limestones. Ordinarily paleontologists tend to stay away from such preservation because the matrix as well as the fossils are coarse, hard chert. These fossils, though, are important because they give strong clues about the depositional environment of the sediments. In this case, in situ coral reefs mean shallow water.
This is what the silicified corals look like in this part of the Matred Formation. We are looking down on the top of a colony. The holes represent the original corallites. Material like this cannot be identified to more than the family or genus, but we see enough to know that they are corals.
In this piece the bean-shaped fossils are large benthic foraminiferans that still retain their original calcareous skeletons. The matrix around them has been silicified. This type of preservation remains a mystery, especially when in the same unit we see the same fossils have been silicified and the matrix is not. More geological puzzles!