Where: Sagaing, Myanmar (23.2° N, 94.3° E)

• Paleocoordinates: 11.5° N, 97.6° E (Wright 2013)

• coordinate stated in text

• small collection-level geographic resolution

When: Yaw Formation, Late/Upper Eocene (37.2 - 33.9 Ma)

• "U–Pb dating of a tuff layer (Licht et al. 2019), magnetostratigraphy, U–Pb apatite dating and apatite fission track dating (Westerweel et al., 2020) provide an age of c. 38–37 Ma, which is also supported by the palynological evidence discussed below and in Huang et al. 2020, Huang et al. 2018." (Huang et al. 2023)

• bed-level stratigraphic resolution

Environment/lithology: fluvial; lithified sandstone and mudstone

Size class: microfossils

Collection methods: chemical

• "Two palynological processing methods were performed to ensure maximum recovery. One set of samples was processed for quantitative analysis. The processing was as follows: 1.3 g of sample was boiled in 10% sodium pyrophosphate, and then treated with 10% HCl, and sieved with 5 μm and 212 μm meshes. The sample was then heated in acetolysis mixture to 100 °C. Bromoform-treatment was applied to separate any remaining inorganic fraction to produce residue. A second set of selected samples was processed mainly for microphotography. The processing method was as follows: 30 g of washed and dried sample was treated with 10% HCl and 40% HF. Then a heavy liquid separation was used to separate the organic and remaining inorganic fractions. All resulting residues were mounted on a slide in glycerin and sealed with paraffin for light microscope (LM) observation. Residues were further used for analysis with LM and scanning electron microscopy (SEM) at the Department of Palaeontology (DoP), University of Vienna, Austria. Details on the two methods were presented in Huang et al. (2020)." (Huang et al. 2023)

Primary reference: H. Huang, R. J. Morley, A. Licht, G. Dupont-Nivet, D. Pérez-Pinedo, J. Westerweel, Z. Win, D. Wa Aung, E. Budi Lelono, G. N. Aleksandrova, R. K. Saxena and C. Hoorn. 2023. A proto-monsoonal climate in the late Eocene of Southeast Asia: evidence from a sedimentary record in central Myanmar. Geoscience Frontiers 14(1):101457 [B. Allen/B. Allen]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 227632: authorized by Bethany Allen, entered by Bethany Allen on 24.10.2022

Creative Commons license: CC0 (CC0)