Here’s another on my favorite YEC stumpers. 
Most of us have heard of the Lake Suigetsu varve record, individual layers in the lake deposited twice yearly (in summer and winter) for the last 150,000 years and which the last 60,000 years are used in C14 calibration.
Lake Suigetsu Varve Project
Creationists hand wave away the evidence by claiming Da Flud deposited all those varves through a series of hyper-rapid water “pulses” (whatever they are). What they won’t tell you is the varve layers in the lake can be cross-correlated and synchronized with volcanic eruptions in Japan and Korea going back 150,000 years. Turns out every volcano has a unique geochemical signature which allows ash in specific layers to be traced to specific eruptions. When that is done the age of the varves determined by counting precisely matches the radiometric age of the volcanoes.
Identification and correlation of visible tephras in the Lake Suigetsu SG06 sedimentary archive, Japan: chronostratigraphic markers for synchronising of east Asian/west Pacific palaeoclimatic records across the last 150 ka
Smith et al
Quaternary Science Reviews: Volume 67, 1 May 2013, Pages 121–13
Abstract: The Lake Suigetsu SG06 sedimentary archive from Honshu Island, central Japan, provides a high-resolution palaeoenvironmental record, including a detailed record of explosive volcanism from Japan and South Korea. Thirty visible tephra are recorded within the 73 m-long SG06 core, which spans the last ∼150 ka. Here we describe and characterise these tephras based on major element glass composition, which is useful for the identification and correlation of these tephras and the age models of the records in which they are found. Utilising the large number of radiocarbon measurements ( n > 600) from terrestrial plant macrofossils in the Lake Suigetsu SG06 record, we are able to provide precise and accurate ages for the tephras from eruptions within the last 50 ka. Glass compositional data of some of the largest eruptions from Japan (K-Ah, AT, Aso-4, Aso-A, Aso-D, and Ata; sampled at proximal outcrops) are also presented. These data show that the major element glass chemistry is distinctive for many of the visible SG06 tephra units, and allows some of the layers to be correlated to known eruptions from volcanoes in Japan and South Korea, namely K-Ah (SG06-0967), U-Oki (SG06-1288), AT (SG06-2650), Aso-4 (SG06-4963/SG06-4979), K-Tz (SG06-5181), Aso-ABCD (SG06-5287) and Ata (SG06-5181). The following ages were obtained for the SG06 tephra units: 3.966–4.064 cal. ka BP (95.4% probability range) for the SG06-0588 tephra, 10.242–10.329 cal. ka BP (95.4% probability range) for SG06-1293, 19.487 ± 112 SG062012 ka BP (2 σ ) for SG06-1965, 28.425 ± 194 SG062012 ka BP (2 σ ) for SG06-2504, 28.848 ± 196 SG062012 ka BP (2 σ ) for SG06-2534, 29.765 ± 190 SG062012 ka BP (2 σ ) for SG06-2601, 29.775 ± 191 SG062012 ka BP (2 σ ) for SG06-2602, 43.713 ± 156 SG062012 ka BP (2 σ ) for SG06-3485, 46.364 ± 202 SG062012 ka BP (2 σ ) for SG06-3668, 49.974 ± 337 SG062012 ka BP (2 σ ) for SG06-3912, 50.929 ± 378 SG062012 ka BP (2 σ ) for SG06-3974, and improved ages for two of the most important tephra markers across Japan, the K-Ah (7.165–7.303 cal. ka BP at 95.4% probability range; SG06-0967) and AT tephra (30.009 ± 189 SG062012 ka BP at 2 σ ; SG06-2650)
The paper is open access but the hosting site won’t allow hot-linking. It can be found on Google Scholar with a simple search.
Any YECs out there willing to explain how the physical counting of the varve layers matches the age of the volcanoes across the whole 150,000 count varve record?