The PETM was an abrupt climate shift ~55 m.y. ago associated with a host of biotic changes and a negative CIE in oceanic and continental reservoirs. Many of the postulated causes of the event involve introduction of a large amount of CO2 or CH4 into the ocean-atmosphere system and result in a rapid shoaling of the lysocline and CCD. This response can be tested with an examination of foraminiferal preservation and detailed counts of fragmentation, fish debris, and pyrite in conjunction with CaCO3 content. Detailed analysis of foraminiferal preservational proxies (i.e., fragmentation, benthic/planktonic foraminiferal ratios, coarse fraction, and CaCO3 content) from Shatsky Rise PETM sections and visual observations of foraminiferal preservation indicate that fragmentation most accurately mirrors foraminiferal preservation. CaCO3 content and benthic/planktonic ratios also identify intervals of poorest visual preservation. Fragmentation, CaCO3 content, and fish debris data indicate abrupt lysocline shoaling and dissolution of CaCO3 within the sediment column (carbonate burn-down). Minimum lysocline shoaling is ~500 m in the tropical Pacific Ocean, significantly greater than model estimates assuming input of CO2 or CH4 in the deep Atlantic. Increases in pyrite at the basal lithologic contact indicate depleted O2 in pore waters possibly due to CH4 oxidation in the water column or an increase in Fe supply to the ocean.