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We propose a model for interpreting highly variable ion composition ratios insolar energetic particles (SEP) events recently observed by Parker Solar Probe(PSP) at $0.3 - 0.45$ astronomical unit. We use numerical simulations tocalculate SEP propagation in a turbulent interplanetary magnetic field with aKolmogorov power spectrum from large scale down to the gyration scale ofenergetic particles. We show that when the source regions of different speciesare offset by a distance comparable to the size of the source regions, theobserved energetic particle composition He/H can be strongly variable over morethan two orders of magnitude, even if the source ratio is at the nominal value.Assuming a $^3$He/$^4$He source ratio of $10 \%$ in impulsive $^3$He-richevents and the same spatial offset of the source regions, the $^3$He/$^4$Heratio at observation sites also vary considerably. The variability of the ioncomposition ratios depends on the radial distance, which can be tested byobservations made at different radial locations. We discuss the implication ofthese results on the variability of ion composition of impulsive events and onfurther PSP and Solar Orbiter observations close to the Sun.

Variable Ion Compositions of Solar Energetic Particle Events in the Inner Heliosphere: A Field-line Braiding Model with Compound Injections