The southern margin of the Barberton Greenstone Belt in Eswatini limits one of the world’s oldest well-preserved sedimentary and volcanic sequences, 3.57 to 3.2 Ga old. In a segment along that margin, older mafic and ultramafic volcanic rocks were thrust over the youngest strata (quartz-rich sandstones and conglomerates) before being folded and imbricated in thrust slices. Samples described in this publication comprise tabular data of (1) sample locations and crystallization ages of zircons which were extracted from thin tuffaceous units in the thrust sheet, (2) analytical data from laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS), supporting these ages, and (3) quantitative measurements of ductily deformed conglomerate clasts. Field data were collected 2012-2019; U-Pb analyses performed in 2020. The data presented here are the basis for geological maps and cross sections, and are visualized as concordia diagrams form part of in the related publication (Heubeck et al.. 2023).