Millook Haven geological structures

Detail of part of the turbidite sequence of the Crackington Formation (upper Carboniferous) at Millook Haven, north Cornwall, lit by the late afternoon sun. This photo shows alternating sandstone (pale) and shale bands on the inverted limb of one of the recumbent chevron folds. The compass-clinometer is located on the stratigraphic base of one of the sandstone bands, which displays a fining-up sequence (in this case downwards, since it is inverted). Just to the left of the compass-clinometer, the coarser sandstone base has slumped stratigraphically down (in this case appearing up) into the underlying muddy layer (now grey shale). This shows how you can use sedimentary structures to deduce whether the rocks are the right way up, or whether as in this case, they have been subsequently turned upside-down.

An unusual view of the intensely folded turbidite sequence in the Crackington Formation (upper Carboniferous) at Millook Haven, north Cornwall. The northward-dipping limbs of the folds e.g. the striped sequence in the lower left quadrant are the inverted (upside-down) limbs.

Cascades of recumbent chevron folds in the turbidite sequence of the Crackington Formation (upper Carboniferous) at Millook Haven, north Cornwall, lit by the late afternoon sun. The northward-dipping (to the left) limbs of the folds are the inverted (upside-down) limbs.

Cascades of recumbent chevron folds in the turbidite sequence of the Crackington Formation (upper Carboniferous) at Millook Haven, north Cornwall, lit by the late afternoon sun. The northward-dipping (to the left) limbs of the folds are the inverted (upside-down) limbs.

The is an unusual detail view of the rocks at Millook Haven, north Cornwall. The striped rocks are turbidites belonging to the Crackington Formation (upper Carboniferous). Way-up structures in the sandstone bands such as fining-up sequences, small-scale slump structures, ripple marks and grooves, etc, demonstrate that these northward dipping rocks (part of the famous chevron fold sequence) have been inverted and are upside-down.

Cascades of recumbent chevron folds in the turbidite sequence of the Crackington Formation (upper Carboniferous) at Millook Haven, north Cornwall, lit by the late afternoon sun. The northward-dipping (to the left) limbs of the folds are the inverted (upside-down) limbs.

Cascades of recumbent chevron folds in the turbidite sequence of the Crackington Formation (upper Carboniferous) at Millook Haven, north Cornwall, lit by the late afternoon sun. The northward-dipping (to the left) limbs of the folds are the inverted (upside-down) limbs. The walking-stick in the lower middle is approx. 0.9 m long.

Cascades of recumbent chevron folds in the turbidite sequence of the Crackington Formation (upper Carboniferous) at Millook Haven, north Cornwall, lit by the late afternoon sun. The northward-dipping (to the left) limbs of the folds are the inverted (upside-down) limbs.

Cascades of recumbent chevron folds in the turbidite sequence of the Crackington Formation (upper Carboniferous) at Millook Haven, north Cornwall, lit by the late afternoon sun. The northward-dipping (to the left) limbs of the folds are the inverted (upside-down) limbs.