Latest Danian Event

The Latest Danian Event (LDE) was a hyperthermal event that occurred at the end of the Danian stage.

Timing

The LDE is believed to have been approximately 170-230 kyr in duration and occurred about 62.18 Ma.^[1] The LDE consisted of two distinct δ¹³C excursions, which are referred to as LDE1 and LDE2, respectively.^[2]

Effects

The LDE was similar in essence to the Palaeocene-Eocene Thermal Maximum (PETM), although significantly smaller in magnitude.^[3][4] Seawater warmed by about 2-3 °C in both the surface oceans and the deep oceans.^[5] The LDE led to a significant shoaling of the oceanic lysocline, which is evidenced by the greatly reduced calcium carbonate preservation that occurred during the event.^[6] Significant black shale deposition occurred during the LDE, a consequence of sea level rise and clastic starvation combined with enhanced nutrient input into the ocean and anoxia.^[7]

The planktonic foraminifer genus Morozovella, especially the species M. angulata, increased in abundance.^[8] Sediment core analysis from Shatsky Rise shows that 40 kyr before LDE1, an increase in phytodetritus occurred, increasing the abundance of the benthic foraminifer Tappanina selmensis. The start of LDE1 brought about oligotrophic conditions on the seafloor, which continued through LDE2.^[2] Unlike the PETM, the LDE did not result in an extinction of benthic foraminifera.^[1]

See also

• Palaeocene-Eocene Thermal Maximum
• Eocene Thermal Maximum 2
• Late Lutetian Thermal Maximum
• Tortonian Thermal Maximum