The Mid to Late Miocene Pedogenic Carbonate Derived d13C and d18O Signature of Irsee and Hammerschmiede, South Germany

The Miocene Epoch was important because of its several climatic cycles that include extreme warming and cooling. Afterwards of the Mid Miocene Climatic Optimum (MMCO) there was an abrupt cooling and drying. Simultaneous changes in the geosphere had paved the way for Graminoid establishment and subsequent faunal evolution in the Paratethys realm. For a better understanding of the concerned paleocosystem this study takes an effort to reconstruct the vegetation and climate pattern of the transition phase between the Middle Miocene to the Late Miocene (12.207 – 11.154 Ma) from the δ13C and δ18O values of the pedogenic carbonates from Hammerschmiede outcrop and Irsee drill-core of the North Alpine Foreland Basin (NAFB). The carbon isotopic range from -10.90‰ to -4.01‰ is denoting that the carbonate crystallisation took place in a C3 dominant paleoecosytem however with declining of the timescale, presence of C4 plant taxa is obvious. The oxygen isotope with a range from -7.21‰ to -4.74‰ bears the marks of global cooling events (Mi) however the evaporative Paratethys Sea and the warm Atlantic Ocean inflow which resulted in amount effect were supposed to have overwhelmed the Mi effects. This geochemical study which is first of its kind in this section of the NAFB plateau proposes a C4 vegetation development at here under a relatively dry and possibly warm climate from the verge of the Early Late Miocene.