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UNIT F

Red ball iconSTRATIGRAPHY OF THE
MIDCONTINENT RIFT SYSTEM IN IOWA

 

UNIT F


The third clastic unit encountered in the Eischeid well, Unit F (depth 4690 to 7020 feet; 1407 to 2106 m), was subdivided into three generally fining upwards sequences labeled (top down) F 3, F 2, and F 1 by Witzke (1990). These sequences grade from basal red brown to pale gray (clear), very fine- to fine- grained sandstones upwards to red brown (in part mottled light green to gray green) to red (in part mottled light green to gray green) shales and siltstones (Witzke, 1990). The sandstones have a mean framework grain composition (click here for QFL information) of Q=69 F=22 L=9 (Ludvigson et al., 1990).

click for depositional model for Unit F

click for references cited

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