Abstract: Palynology and Organic/Isotope Geochemistry of the Mae Moh Basin, Northern Thailand

Le Van Minh, Teofilo Abrajano, Elliott Burden, Linda Winsor, Benjuvun Ratanasthien

The Mae Moh basin is one of several Tertiary intermontane basins in northern Thailand, whose evolution has been linked to the collision of the Indian plate with the Eurasian plate since the early Eocene. As in most of these basins, lacustrine/ swamp sedimentation in the Mae Moh basin can be broadly divided into an Oligocene to Miocene synrift sequence and a Miocene to Quaternary postrift sequence.

The dominance of swamp flora recognized from spore and pollen assemblages (e.g., Polypodiidites usmensis, Verrucatosporites, Cyrtostachys), as well as the abundance of macrophytes and woody debris, indicate overwhelming hot and humid swamp conditions, with lake development restricted to relatively small areas. The distribution of alkanes and their compound-specific carbon isotope compositions are used to further show climatic variations affecting the lake/swamp ecology during the deposition of the synrift sequence.

AAPG Search and Discovery Article #90982©1994 AAPG International Conference and Exhibition, Kuala Lumpur, Malaysia, August 21-24, 1994