This material is based upon work supported by the National Science Foundation under Grant No. 1053530

Collaborative Research: Northern Embayment Lithosphere Experiment (NELE)

Pieces of the Puzzle

Present Sediments of the ME hide a long, complex geological history.

The major known features associated with the northern ME are shown below superimposed on gravity and magnetic anomaly maps.

The ME is associated with a relative high in Bouguer gravity suggesting mass excess relative to the craton to the north and west. A prominent feature in the lower crust is the “rift pillow” which could be due to preCambrian to Cambrian crustal underplating/modification or be a relict structure from earlier times.

Bouguer gravity anomaly map for the central U.S.
The ME is associated with a relative high in Bouguer gravity suggesting mass excess relative to the craton to the north and west. A prominent feature in the lower crust is the “rift pillow” which could be due to preCambrian to Cambrian crustal underplating/modification or be a relict structure from earlier times.

Magnetic anomaly map shows signatures of prominent syenitic plutons (probably of late Cretaceous age) and others of unknown age.

Magnetic anomaly and seismicity map for the central U.S.
Mississippi Valley graben (MVG) (Reelfoot rift) merges with the Rough Creek graben. Evidence for MVG primarily comes from magnetics and reflection studies. The NMSZ occurs in the middle of the MVG and is associated with unusual plutons and other fault structures like the Blythville arch.