Ratten Clough, Cliviger Valley

© Craven & Pendle Geological Society

Rough Rock at the head of Ratten Clough

Entrance to Ratten Clough
Grid Ref: [SD 8900 2670]

In the vicinity of Ratten Clough, Cliviger Valley is stratigraphically divided in two by the Cliviger Valley Fault, which roughly follows the main A646 (T) road. The north-east side (downthrow) is dominated by Coal Measure (Westphalian) rocks whilst the Millstone Grit Group (Namurian) form the craggy outcrop along Thieveley Scout to the south-west.

Ratten Clough is a typical Cliviger valley stream section exposing rocks of the Millstone Grit Group: the Gastrioceras subcrenatum marine band has been found above the waterfall thus bringing you into the Coal Measures.

The short strenuous climb up the clough rewards you with spectacular views of the surrounding countryside and also helps you to appreciate the regional geology and geomorphology of the valley.  The lower reaches of Ratten Clough expose Holcombe Brook Grit, the Cancelloceras cancellatum marine band, and the Lower Haslingden Flagstones. The Cancelloceras cumbriense marine band sits on top of the Lower Haslingden Flags but is not seen in Ratten Clough.

The upper reaches of the clough begin at the Upper Haslingden Flagstones. Above the flagstone lies the Rough Rock - a classic example of a Millstone Grit. The Rough Rock marks the top of Ratten Clough and therefore the top of the Namurian. The Gastrioceras subcrenatum marine band lies just above a waterfall that marks the headwater of the stream.

NB: The localities follow Chapter 8 in the Yorkshire Geological Society's Yorkshire Rocks and Landscape - A Field Guide. (Holcombe Brook Grit is seen prior to Locality 1; the Lower Haslingden Flags are exposed 20 metres beyond locality 1). Riddle Scout can be observed across the valley from Locality 3.

Holcombe Brook Grit at stream level

Holcombe Brook Grit
Grid Reference: [SD 8900 2670]

Holcombe Brook Grit, the uppermost sandstone in the Marsdenian "Middle Grits", is exposed in the stream bed at the entrance to Ratten Clough. 

The Holcombe Brook Grit is associated with the Holcombe Brook Coal after after a long absence, recent heavy rain (2002) has eroded and washed away the outcrop at stream level.  The weakly developed Holcombe Brook Coal and associated seat earth below have been recently exposed for the first time in many years.

Holcombe Brook Coal

Holcombe Brook Coal and seat earth.

Holcombe Brook Coal
Grid Reference: [SD 8900 2670]

Holcombe Brook Grit, the uppermost sandstone in the Marsdenian "Middle Grits", is exposed in the stream bed at the entrance to Ratten Clough.

Also the associated Holcombe Brook Coal after after a long absence is now viewable.  Recent heavy rain (2002) has eroded and washed away the outcrop at stream level.  The weakly developed Holcombe Brook Coal and associated seat earth are shown in the photograph.

Cancelloceras cancellatum Marine Band Grid Reference [SD 8921 2685]

About 25 metres up Ratten Clough lies a small shale cliff. This shale marks the occurrence of the goniatite Cancelloceras cancellatum.  The goniatite can also be seen extensively in the bed of the stream along with bivalves as shown in the photograph below.

Cancelloceras cancellatum in Ratten Clough

Notice Cancelloceras cancellatum on the lower ledge to the left of the hammer. Like so many outcrops in the Pennines, timing is all important as the stream level was sufficiently low to capture this photograph.

This marine incursion marks the end of the Marsdenian Stage (R2) and the beginning of the Yeadonian Stage (G1). In Sequence Stratigraphy terms this marine horizon represents a maximum flooding event.

Lower Haslingden Flags

Lower Haslingden Flags
Grid Reference [SD 890 267]

Our next locality is the Lower Haslingden Flags exposed in a spectacular Cliviger Valley waterfall with plunge pool. The more resistant nature of the sandstone withstood the impact of glacial meltwater rushing down the Cliviger Valley towards Wakefield.

The Lower Haslingden Flags are typically fine-grained sandstones and siltstones of a greenish facies that lie between the Cancelloceras cancellatum and Cancelloceras cumbriense marine bands.

They are considered to be 'bar-finger' delta deposits having an east-west origin. In the Cliviger Valley they are a feeble development compared to the more spectacular flagstones seen in the Rossendale Valley e.g. Brittania Quarry and Leas Moor Quarry near Stacksteads.

Upper Haslingden Flags
Grid Reference [SD 890 267]

Upper Haslingden Flags

The Upper Haslingden Flags are exposed at the top of Ratten Clough. They are interbedded fine-grained sandstones and siltstones of a green facies that lie above the Cancelloceras cumbriense marine band.

The thicker unit seen in the photograph at the top is the Rough Rock, which at this locality erodes down into the Upper Haslingden Flags by about 10cm.

The underside of the Rough Rock contains spectacular logs of calamites and other tree debris which probably accumulated as a log jam. Similarly to the Lower Haslingden Flags, they are best seen in the Rossendale Valley.

Rough Rock
Grid Reference [SD 890 270]

The Rough Rock marks the top of Ratten Clough and is the most extensive sandstone in the Millstone Grit Group.  It is frequently craggy as shown in the photo and is commonly quarried. It is a very coarse grained yellow-brown quartz-rich sandstone showing large scale planar cross-bedding.

Rough Rock in Ratten Clough

Calamites tree trunks are common in the sandstone. It is commonly believed that the Rough Rock formed an extensive sheet delta covering much of the Pennine Basin. The Sand Rock Mine and the Gastrioceras subcrenatum marine band are obscured at Ratten Clough.

It is instructive to view the opposite side of the Cliviger Valley, across the Cliviger Valley Fault, where a series of Westphalian cycles are exposed. e.g. Riddle Scout.

Can you see the bird of prey (Peregrine Falcon) on the ledge halfway down the cliff watching my every move!!

The photograph (below) shows an enormous block of compressed vegetation.  In fact Paul Wignall was heard to comment that in all the research work done on the Millstone Grit Group throughout the Pennines, he had never seen such large block of decayed vegetation.

In this part of the section visitors must take care as the blocks of Rough Rock and associated carbonaceous blocks is in an area liable to collapse. The 'camber' in the beds is caused by excess water penetrating the shale horizons which in turn allow the heavier gritstone beds to 'slide' down!

Extensive log jam in the Rough Rock

Riddle Scout
Grid Reference [SD 894 275]

Riddle Scout

Riddle Scout : Ruddle - Saxon for red, Scout - Norman for High Rock) is the former location of an ironstone mine according to John Aitken (1878). The iron extracted from the mine may have been smelted locally. There is also evidence of an Iron Blast Furnace that was driven by a water wheel near the present day trout fishery. The iron ore was believed to have been carried off on pack-horse via the Long Causeway to Yorkshire (Sheffield).

Today, geologists' hold the view that the iron ore was probably extracted from siderite concretions that lie within marine shales. Surprisingly it is thought that as much as 39.2% iron was contained in the siderite concretions.