Lacustrine soft-sediment deformation structures (seismites) are widely used as paleoseismic archives, yet the resolution and spatial representativeness of the record sampled by a single drill core remain poorly constrained. Here we develop a probabilistic framework to quantify sampling completeness for the late Pleistocene Lisan Formation in the Dead Sea Basin. We compile a catalog of 383 seismites from 23 marginal outcrops between two gypsum markers, co-evaluated with data from the ICDP--5017 core. Horizontal tracings of 35 thin seismites are converted to one-dimensional boxcar signals to characterize lateral discontinuity and to estimate the probability that a vertical core of diameter $\ell$ intersects a single thin seismite. For $\ell = 7$~cm, we obtain a hit probability of $P_{\mathrm{hit}} \approx 0.38 \pm 0.16$. Using statistics of the seismite population in all sampled outcrops, we predict the expected number of events in each vertical log and estimate the fraction of missed seismites. Marginal sections miss about one third of the thin seismites, whereas the basin-center core records a much denser sequence. A linear regression model ($R^2 \approx 0.91$) shows that record resolution is primarily controlled by lamina density, and deformation degree and abundance. Our approach provides quantitative bounds on how accurate is the earthquake history recorded in a single core.