The term Middle Miocene disruption, alternatively the Middle Miocene extinction or Middle Miocene extinction peak, refers to a wave of extinctions of terrestrial and aquatic life forms that occurred around the middle of the Miocene Epoch, c. 14.8 to 14.5 million years ago, during the Langhian stage of the Miocene.
Madelaine Bohme observed the occurrence of Varanidae, Chamaeleon, Cordylidae, Tomistomidae, Alligatoridae, and giant turtles which indicate survival through the Miocene Climatic Optimum (18 to 16 Ma) in Central Europe (42W 45 N palaeolatitude). A major and permanent cooling step occurred between 14.8 and 14.1 Ma, associated with increased production of cold Antarctic deep waters and a major growth of the East Antarctic ice sheet. Two crocodiles of the genera Gavialosuchus and Diplocynodon were noted to have been extant in these northern latitudes prior to the permanent cooling step then became extinct 13.5 to 14 Ma.
A Middle Miocene delta 18O increase, that is a relative increase in the heavier isotope of oxygen, has been noted in the Pacific, the Southern Ocean and the South Atlantic.
Famous quotes containing the words middle and/or disruption:
“During a walk or in a book or in the middle of an embrace, suddenly I awake to a stark amazement at everything. The bare fact of existence paralyzes me... To be alive is so incredible that all I can do is to lie still and merely breathe—like an infant on its back in a cot. It is impossible to be interested in anything in particular while overhead the sun shines or underneath my feet grows a single blade of grass.”
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“[Film noir] experiences periodic rebirth and rediscovery. Whenever we have any moment of deep societal rift or disruption in America, one of the ways we can express it is through the ideas and behavior in film noir.”
—John Briley (b. 1925)