The Porch

The doorway to the porch

Moving anti-clockwise around the tower, the porch is the next interesting feature at St. Helen’s church and the current guide shows that it was built in the 15th century, with the later addition of the south aisle.

Looking at the porch and south aisle together, however, the walling appears to be very uniform – in colour, texture, weathering, block size and tool marking - and the masonry is bonded together. Compared to the stonework in the tower, the levels have been much more carefully set out and it provides a good example of the use of “Rotherham Red” sandstone for ashlar work.

General views of the porch

The degree of weathering to the sandstone exposed on the 3 elevations of the porch varies and, in places, softer beds have been scoured away and deeply eroded. Along with the tower, it has been subjected to the south-westerly wind and rain since its construction and it was also fully exposed to the pollution from the Orgreave Coking Works, before this site was closed down.

Details of the porch roof and sundial

The coping stones and the ridge stones to the plain tiled roof covering, which is quite recent, are uniformly weathered and blackened and they would appear to be original, with the only stone renewal being to the cuboid apex finial, upon which is set a sundial of unknown date.

A detail of the limestone arch

Although the large square block is of Rotherham Red sandstone – a variety that is slightly purple in colour – it is not possible to identify the provenance of the other stones used in its construction, without the benefit of a much closer inspection.

The pointed arch to the doorway of the porch is built of limestone, which an examination with a hand lens will confirm as an oolitic limestone of Jurassic age; however, it is quite unlike the dolomitic limestone of Permian age that is seen in the tower and possesses very different weathering characteristics - especially its chemical resistance to acid rain.

Installed as part of one of two phases of restoration undertaken during the later part of the 19^th century, the renewed arch retains the old Rotherham Red sandstone hood moulding, complete with carved head stops that have nearly eroded away.

The Tower

St. Helen's church tower

Sir Nikolaus Pevsner described St. Helen’s church - in Treeton - as a very confusing building and, having had a good look around the exterior and interior, I have to agree with him.

The description of St. Helen's church by Sir Nikolaus Pevsner

As a geologist, with an interest in building stones, I have a good eye for recognising the various patterns that can be seen in the stonework of an historic building - and the construction history of St. Helen's church particularly intrigues me.

A general view

Treeton Rock forms the escarpment upon which St.Helen’s church is set but, being an inferior building stone, the principal building stone used here was quarried from the nearby Mexborough Rock – locally known as “Rotherham Red” sandstone – which is used throughout the external fabric and forms the base of the 12th century tower.

The west elevation

The masonry is roughly squared and irregularly coursed, with larger blocks used for the quoins, and appears to be built in a single phase. The stonework is uniformly weathered, with a general blackening of the stone, but later repairs can quite clearly be distinguished by their colour, shape and tooling characteristics - especially in the structural repairs to the south-west corner.
 

A detail of restoration work

The top of the tower is constructed in dolomitic limestone, which gives St. Helen's church its unique character. Local tradition has it that the stone was robbed from Roche Abbey, after its dissolution, but Pevsner, English Heritage and other authorities give an earlier date to this addition. Like the lower part of the tower, without documentary evidence, the dating and analysis of its construction history has to be very subjective. 

Limestone & Sandstone

Whatever the provenance of the limestone, it was no mean achievement to bring it to Treeton from its nearest possible source - which is several miles away - using the materials handling and transport technology that was available at the time. There is no doubt that this work would have been undertaken at great expense to the landowner at the time.

Geology & Geodiversity in Sheffield

Geodiversity and Geoconservation in South Yorkshire

Having set the wheels in motion to undertake a close examination of the various building stones used in the construction of St. Helen’s church in Treeton - as well as other old parish churches in South Yorkshire - I looked forward to my next meeting with the Sheffield  U3A Geology Group.

Preparing the talk

The itinerary for this year’s field trips looks very promising and gives me another opportunity to develop my interests in Geotourism and, on this occasion, I was particularly interested in the illustrated talk that would be given by the Sheffield Area Geology Trust.

I was curious to know a little more about the geology of Sheffield, having already spent much of my working life surveying a wide variety of sites in the other boroughs  of South Yorkshire - in Rotherham, Doncaster and Barnsley.

Although I know the city of Sheffield quite well, and have surveyed many of the geological sites that fall within the boundaries of the Peak District National Park, I haven’t looked at the geology within the city boundaries in any detail. 

Nether Edge Bowling Club

Over 25 members of the group turned up at Nether Edge Bowling Club – on a very wet day – to listen to a very well prepared and informative illustrated talk that gave me, at least, a much better insight into the structural geology of the Sheffield region than I had had before.

The geology and river drainage systems in South Yorkshire

St. Helen's Church in Treeton

A general view of St. Helen's church in Treeton

When working out in the field, people often stop to ask me what I am doing and, when I explain that I am a geologist, many of them continue the conversation by talking about archaeology. I don't make any effort to correct them, but it has made me realised that there are many similarities between these disciplines.

A geological map of the area around Treeton

A lot of the work that I have undertaken as a building stone consultant entails tasks that might be delegated to an archaeologist, rather than a geologist – such as recording the fabric of an ancient stone building - and following a recent resurgence in my interest in old churches, I decided to investigate the construction history of St. Helen’s church in Treeton.

A general view of the tower at St. Helen's church

Set upon an escarpment of Treeton Rock that overlooks the River Rother, its tower can be seen from miles away and legend has it that the stone used to extend the tower was robbed from Roche Abbey - after its dissolution by Henry VIII.

 

Roche Abbey