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During Integrated Ocean Drilling Program (IODP) Expedition 313, Miocene intervals of midshelf clinoforms were drilled in the New Jersey shallow shelf at three sites (M0027, M0028, and M0029), complementing the coastal plain to slope core data sets and building a large “New Jersey transect” across the U.S. Atlantic passive margin. Despite the difficulties of coring in the sandy shallow shelf, Expedition 313 successfully collected a total of 1311 m of core with ~80% recovery for target intervals (see the “Expedition 313 summary” chapter [Expedition 313 Scientists, 2010a]). The main goals of Expedition 313 were to estimate the time, amplitudes, rates, and mechanisms of sea level change and to evaluate sequence stratigraphic facies models that predict depositional environments, sediment compositions, and stratal geometries in response to sea level change.

The lithostratigraphic descriptions of split cores show sand-, sandy silt-, and silt-dominated continuous successions of shallow-marine (shoreface to shelf) sediments developed in the late Eocene to middle Miocene that form more than 10 sedimentary cycles. These sediments seem to reflect 50–100 m sea level changes controlled by global eustasy, high sediment supply, and some local factors during the time interval from 34 to 13 Ma (see the “Expedition 313 summary” chapter [Expedition 313 Scientists, 2010a; Miller et al., 2013a, 2013b]).

Our purpose is to detect stratigraphic trends of Miocene successions by analyzing the drilled sediments for characteristics of grain size, grain-size frequency, and changes in distribution and by constructing mean grain-size curves. Saito (1996) and Hoyanagi and Omura (2001) analyzed grain sizes in the Pleistocene muddy successions of the New Jersey shelf slope (Ocean Drilling Program [ODP] Leg 150) and shelf margin (ODP Leg 174A). However, our target intervals are Miocene shallow-marine successions drilled on the New Jersey shallow shelf.