SEDIMENTOLOGY AND STRATIGRAPHY
mation is predominantly light olive gray (5Y6/1) to olive gray (5Y5/1) with moderate red-brown (10R4/6) mottling. The moderate red-brown mottling varies from irregular ovals several millimeters in length to streaks which are slightly greater than one centimeter. In the area of Raritan, New Jersey, to the southwest, the moderate red-brown mottling is vis- ible in the sidewalls of the clay pits and is only present where the clay is directly overlain by a thin ironstone layer. The sediment samples are very thinly bed- ded. The clay is dense to very dense and becomes more difficult to split open with increasing depth. The clay becomes dry at depth and plasticity for the unit is generally high.
The clay is commonly adjacent to predominantly fine to medium-grained quartz sand layers. As represented by the filled black circles in Figures 3 to 5, river channel sands are incised into the clay from locations IT-305 to D12 and from IT-044I to IT-005. The thickness of the distributary channel sands aver- ages 13.5 m, but reaches 14.5 m thick at GW-29 (Figure 6).
The lower unit of the Raritan Clay underlies the entire study area, with the exception of the western quarter of Section 1/9/ of the Fresh Kills Landfill (though an outlier exists at the loca- tion of IT-010). At locations IT-511 and IT-044I, the lower clay unit has been interpreted as residing in a slumped river channel (Figure 5). The slumped sediments may have originated as the result of sediment consolidation land- slides, glacio-isostatic deformation, or possibly due to an episode of seismic activity.
Raritan Clay- Upper Unit
The upper unit of the Raritan Clay is present under the southeast corner of Section 1/9 (Figures 3 to 5), the eastern half of Section 2/8 south of the Toe of the Buried Escarpment (Figures 3 and 6), the southwest quarter of Section 2/8 (Figures 3) and the Brookfield Avenue Landfill (Figures 3 and 7). From loca- tions IT-045I to IT-307 (Figure 3), the upper unit is overlain by a light gray (5Y6/1) predominantly very fine to fine sand layer of limited areal extent.
Figure 3 indicates that the upper unit is complexly interbedded with the lower unit under the Fresh Kills Landfill, and is 0-14.1 m thick varing in color from olive gray (5Y4/1) to olive black (5Y2/1).
48 TPG
Apr.May.Jun 2016
In contrast, the upper unit exists only as outliers under the Brookfield Avenue Landfill. Bedding is very thin. Silt con- tent is moderate to high and very fine to fine sand is present in pockets and as laminae. Mica is uncommon to common, plant fragments are absent to common and iron sulfide nodules are occasionally present. The sediment samples are stiff and dense, plasticity is slight to moder- ate and dilatancy is slight to moderate when moist, though moisture content is generally low. Lignite laminae from less than one millimeter to a few millimeters thick and lignite interbeds are common at locations IT-310, GW-29, and PZ-2BR (Figure 3). The hydraulic conductivity is very low to low depending on the silt and sand content. Sulfurous odors are apparent with freshly opened soil cores. Thin interbedded layers of sand with very fine to fine sand grains are present in the upper unit from IT-307 to GW-29 (Figure 3). In association with the layers of interbedded sand, a thicker lenticular body of sand is present at the location of boring O-20.
The depostitional environment for the entire Raritan Clay within the study area has been interpreted by the author as either the interdistributary bay or an upland restricted deltaic environ- ment such as a floodplain containing swamps or marshes. Lusczynski and Swarzenski (1966), Buxton et al. (1981) and Smolensky et al. (1989) have made similar interpretations for the environ- ment of deposition for the Raritan Clay in Brooklyn, Queens and Long Island, New York. Owens and Sohl (1969) interpreted the environment of deposition for the Woodbridge Clay in New Jersey as being lowland swamp or as the inner neritic shelf. Owens et al. (1977) interpreted the sediments as representing prodeltaic deposits. Jengo (1995) interpreted the environment of deposition of the lower part of the Raritan Clay as the delta front. This interpretation was based, in part, on the presence of concretions in the unit with fully marine fossils. However, Jengo considered the upper unit as hav- ing been formed in the floodplains, inter- distributary bays, tidal flats, marshes and mangrove swamps. Sugarman (1996) interpreted the environment of deposition as either the marginal marine or the interdistributary bay.
Conclusions
The consultants who wrote the Fresh Kills Leachate Mitigation System
Project Final Hydrogeological Report (International Technology Corporation et al., 1993) stated that the strata under the study represented the Lower Cretaceous Patapsco Formation due to the dominance of Lower Cretaceous pol- len. The sedimentology and stratigraphy of the Patapsco Formation differs from that of the Cretaceous sediments under the study area. The Patapsco Formation is described as comprising interlensing sands, silts and clays. The clay is thick and massive with laminated silt-clay successions and thinly interbedded fine sand and silty clays. Fine to medium sands predominate. Coarse grained sedi- ments with gravel and coarse sands are less common (Brenner, 1963; Glaser, 1969). However, Owens and Sohl (1969), Soren (1988), International Technology Corporation et al. (1993), Jengo (1995 and 2011) and Sugarman (1996), state that the Farrington Sand and the Lloyd Sand consist of fine to medium sand, with layers of coarse sand with gravel, and fines upward. They also state that the Woodbridge Clay and the Raritan Clay consist of a lower light gray unit with dense refractory clay at the bottom which is overlain by a dark gray unit con- sisting of very thinly bedded micaceous clay with thin layers of very fine sand. From the examination of the sediment cores, the author has determined that the Lloyd Sand exists under the study area as a discrete thick layer of primarily very fine to very coarse sand with layers of gravelly sand. Also evident is that the Lloyd Sand is directly overlain by the Raritan Clay which contains a lower light gray, dense, refractory clay unit and an upper dark gray, micaceous, very thinly bedded clayey silt unit (Figures 3 to 7).
The information gained from the Fresh Kills Landfill and Brookfield Landfill hydrogeological investigations suggests that a division of the Upper Cretaceous sediments under the study area into the Lloyd Sand and the Raritan Clay is reasonable. These formational designations were made based upon the sedimentology of each unit, the strati- graphic interrelationships, and similar manners of deposition to the Farrington Sand and Woodbridge Clay of New Jersey. Considering all of the informa- tion that had been generated by the study, the author views the areas from eastern New Jersey to Staten Island and Long Island as consisting of one contigu- ous depositional region.
www.aipg.org
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64