1. The Permo-Triassic Mass Extinction
Andrew Folfas

2. Statistics Occurred around 251 million years ago
95% of marine taxa wiped out.
70% of terrestrial taxa became extinct.
New forms of life:
Paleozoic: crinoids, bryozoans, brachiopods
Mesozoic: bivalves, gastropods, echinoderms
Global cooling followed by a warming (-1 C/ +3 C).
Trace Iridium found in stratigraphic layers.

3. Theories
High levels of volcanism due to a mantel plume forcing its way to the surface in present day Siberia.
Glaciation occurring due to drop in global temperature levels causing a reduction in sea levels.
Extraterrestrial impact due to a large meteorite (similar to K/T boundary theory).
Convergence of land mass resulting in the loss of costal ecosystems and the creation of Pangea.

4. Siberian Traps

5. Unified Volcanism-Glaciation-Climate Change Theory

6. Early Triassic Pre-Pangea

7. Feasibility of Theories
Volcanism is seen leading to glaciation and global climate change. Plausible evidence in the Siberian Traps, recent studies done on CO2 and SO2 emissions, and reduction of sea level due to glaciation.
Iridium spikes found in layers of sediment at least one meter below the P-T boundary, and lack of evidence of sufficient shocked quartz microspherules.
The primary compacting of Pangea took place earlier in the Permian and does not seem to coincide with the mass extinction event.