Late Maastrichtian Climate Dynamics and the K-Pg Event in Anatolia: Geochemical, Micropaleontological and Cyclostratigraphic Insights

This thesis presents a high-resolution, multi-proxy investigation of the Cretaceous–Paleogene (K–

Pg) transition in Central Anatolia, Turkey, based on integrated biostratigraphic, geochemical,

mineralogical, isotopic and cyclostratigraphic records from the Mudurnu–Göynük and Haymana

basins. Three sections were studied in detail in this thesis: Göynük and Okçular sections of the

Mudurnu-Göynük Basin and Haymana section of the Haymana Basin. The studied Göynük and

Okçular sections reveal a complete succession across the K–Pg boundary, with well-preserved

planktonic foraminiferal biozones spanning the late Maastrichtian (CF4 Zone) through the early

Danian (P1b–P1c zones). A distinguished positive iridium anomaly, sharp extinction of large

planktonic foraminifera, with negative δ¹³C excursion delineate the K-Pg boundary and the global

signal of the Chicxulub impact.

The Haymana section hosts a series of observations. First of all, δ¹³Cbenthic values unsually being

heavier than δ¹³Cplanktonic values. Both values increase throughout the CF1 Zone to K-Pg boundary.

Furthermore, these values show cyclical variations. Spectral analysis of planktonic δ¹³C values

reveals dominant precession cyclicity, suggesting that orbital forcing also modulated climate and

ocean chemistry in the latest Maastrichtian. The elevated benthic δ¹³C record and reduced

Δ¹³Cplanktonic–benthic further indicate disruptions in the ocean carbon cycle and diminished biological

pump efficiency, likely linked to sulfur-rich Deccan volcanism and seafloor acidification.

Together, the results highlight a complex interplay between extraterrestrial impact, massive

volcanism, and orbital forcing in shaping environmental and biotic evolution through the late

Maastrichtian and the K–Pg boundary in Central Anatolia, Turkey.