ORIGINAL PAPER Paleoenvironmental and paleoclimatic conditions during the deposition of the bauxite layer (Upper Cretaceous) using multi-proxy geochemical and palynological analyses, in the Zabirah Area, Northern Saudi Arabia Madyan M.A. Yahya 1 & Mohammed H. Hakimi 2 & Mahmoud A. Galmed 1,3 & Mohamed N. El-Sabrouty 1 & Yasamin K. H. Ibrahim 4 Received: 10 January 2016 /Accepted: 28 December 2017 # Saudi Society for Geosciences 2018 Abstract In this research, Cretaceous claystones in the Az Zabirah area, Northern Saudi Arabia were evaluated to investigate the paleoenvironmental and paleoclimatic conditions during deposition of the claystone sediments. Outcrop samples of claystone from the bauxite zone profile in the Az Zabirah area were analyzed using multi-proxy geochemical and coupled with palyno- logical analysis. Palynological analysis suggested that the age of the Az Zabirah claystones is Maastrichtian of Upper Cretaceous. This evidence is valid due to the presence of microspore taxa Gabonisporis sp. The Az Zabirah claystones have abundant angiosperm taxa, indicating a large terrestrial influx in the interval of the claystone. This finding is confirmed from geochemistry of major and trace elements and mineral compositions. The high concentration of terrestrial detritus oxides, such as SiO 2 , Al 2 O 3 , and TiO 2 , infers that the Az Zabirah claystones were sourced from terrigenous origin. This is consistent with a significant amount of quartz and kaolinite in the Az Zabirah claystones. The claystones could be deposited under oxic paleo-redox and warm-humid with little aridity climatic conditions. This is indicated by their concentration of the trace element concentrations along with their geochemical ratios. Warm-humid climate condition is also largely supported by the presence of a significant amount of kaolinite. Keywords Claystone . Cretaceous . Az Zabirah area . Palynology . Geochemistry paleoenvironmental . Paleoclimate . Northern Saudi Arabia Introduction The dataset used herein is from Az Zabirah area in the Ha’il province, Northern Saudi Arabia (Fig. 1). The research area occupies the north part of Saudi Arabia, which lies between 27° 35′ N and 27° 40′ N and 44° 00′ E and 44° 7′ E (Fig. 1) and has an elevation of 628 m above sea level. The Az Zabirah area is located at about 150 km southwest of the Trans- Arabian pipeline (TAP line) and approximately 180 km north of the town of Buraydah the capital city of Al Qassim province in the northeastern region of Saudi Arabia. The Az Zabirah section also lies at about 484 km northwest from the capital of Saudi Arabia, Riyadh (Fig. 1). Palynological research has gained the distinction of scien- tific discipline since the decade of 90s,, especially after the remarkable studies of the Swedish geologist Lennart von Post. His pioneer works include the pollen diagrams that assisted in the count and identification of pollen grains from the deposits of peat (Stricto and Lato, 2015). In view of the exploration of bauxite ore deposit, the Az Zabirah area of Saudi Arabia has attracted the attention of several researchers and explorers (e.g., Al-Bassam, 2005; Al-Mesbah, 2009). However, palynological research of the Cretaceous claystone in the Az Zabirah area has not been reported yet in any of the previous literature. Thus, there is a prominent knowledge gap in the paleoenvironmental and * Mohammed H. Hakimi ibnalhakimi@yahoo.com 1 Geology and Geophysics Department, College of Science, King Saud University, Riyadh, Saudi Arabia 2 Geology Department, Faculty of Applied Science, Taiz University, 6803 Taiz, Yemen 3 Geology Department, Faculty of Science, Cairo University, Giza, Egypt 4 Earth Science Department, Science College, Baghdad University, Baghdad, Iraq Arabian Journal of Geosciences (2018) 11:15 https://doi.org/10.1007/s12517-017-3379-0