Skipsea 2011.

(Updated 12th July 2011)

Fieldwork on 19th June 2011 by Derek Gobbett, Graham Kings, Jan Harrison, Mike Horne, Rod Towse, Ros Perry, Stuart Jones, Tabitha Dingler, Tony Barker, Tony Felski, Tracy Marsters.

There had been significant erosion of the cliff since 2008. The northern part of the exposure where the gravels underlay the grey clay and peat had slumped. This was not measured due to concerns over safety and because of the slumping. (See photographs).

A horizontal datum line along the cliff face was established using a laser level from the beach and then string and a spirit level. Pegs were positioned along the cliff at this height about 2m apart. The cliff section was logged vertically at these pegs.

A south north datum line was established on the beach. The distance along the line of each peg was measured by sighting it at right angles and the distance from the beach datum line to the cliff was measured for each peg.

Raw data.

Pegs were numbered S1 onwards going south in ascending order and N1 onwards going north in ascending order.

GPS readings (MH).

Our datum line on the beach went from TA 18364 54676 ( second reading was TA 18369 54677) in the north to TA18404 54578 in the south in a direction of about 12 degrees east of south (from GPS). The northern end of the line was measured with a tape to be 4.5m from the cliff and the southern end was 9m from the cliff.

From the south of the mere deposits here are some GPS readings (taken by Mike) for the cliff base (all of them are TA 18xxx 54xxx):- 400 576; 390 587 (near yellow drain pipe) ; 384 596 (orange drain pipe); 377 618 (near peg S1); 363 620 (head of stream section); 380 626 (near peg N1); 391 630; 370 642; 365 643 (gravel deposits); 369 656 ; 362 662; 358 673.

Graham's GPS readings - North end of beach datum line TA 18370 54677 South end of beach datum line TA 18405 54579 (more below).

Peg distances along the datum line and from datum line to cliff. South to North in metres.

South end datum to the cliff 4.56m

South end of datum line to peg S13

under the long orange plastic drain pipe

12.20m North along the datum line (a t l )

peg S13

1.00 (a t l )

peg S12 - 12.45 ( t t c )

2.2 ( a t l )

peg S11 -13.48 (t t c )

1.7 ( a t l )

peg S10 -13.78 (t t c )

2.5 (a t l )

peg S9 - 13.6 ( t t c )

2.2 ( a t l )

peg S8 -13.3 (t t c )

2.29 ( a t l )

peg S7 - 13.0 (t t c )

1.8 (a t l )

peg S6 -13.0 (t t c )

1.9 ( a t l )

peg S5 -12.7 (t t c )

1.87 (a t l ) under the terra cotta drain pipe

peg S4 -13.3 (t t c )

1.8 (a t l )

peg S3- 13.2 (t t c )

1.8 (a t l )

peg S2 -12.1 (t t c )

2.8 (a t l )

peg S1 - 10.4 to the cliff(t t c )

8mtr N along the line(a t l ) peg S1 to N1

[peg S1 to N1 is 7.8m at cliff face; datum line measurement to follow]

Peg N1 - 7.5m to cliff

2m North (a t l )

Peg N2 - 8.0 m to cliff

1.9m North (a t l )

Peg N3 - 8.9m (t t c )

1.0m N (a t l )

Peg N4 - 10.8m (t t c )

1.6m N (a t l )

Peg N5 - 12.4m (t t c )

1.34m N (a t l )

Peg N6 - 13.4m (t t c )

2m N (a t l )

Peg N7 13.6 m (t t c )

1.87 m N (a t l )

Peg N8 13.6 m (t t c )

1.88 m N (a t l )

Peg N9 14.00 (t t c )

2.40m N (a t l )

Peg N10 13.40 m (t t c )

1.95m N (a t l )

Peg N11 - 12.70 m (t t c )

1.26m N (a t l )

Peg N12 -11.80 m (t t c )

2.5m N (a t l )

Peg N13- 12.40 m (t t c )

2.54m N (a t l )

Peg N14 12.50 m (t t c )

Peg N14 to the end of the base line, 25.60 m north

 

North end datum line to the cliff 9.17m (t t c )

Log of cliff at each Peg:-

Peg S13. We have not measured peg S13 since the cliff was all slippage material and it want possible to take accurate measurements without having the need to dig out a lot first.

Peg S12. Above peg. 100 cm boulder clay 150 cm slip material (1 band with sand and gravel at the following intervals.) 50 cm sand 40 cm gravel Soil 20 cm Below peg. 160 cm boulder clay.

Peg S11 Above peg. 200 cm slip material 140 cm sand 90 cm gravel 50 cm soil. Below peg: 60 cm gravel

Peg S10. Under peg: 130 cm clay 70 cm boulder clay Above peg. 50 cm clay 35 cm gravel 30 cm clay 25 cm gravel 70 cm clay 18 cm sand 5 cm gravel 50 cm soil.

Peg S9. Above peg. 70 cm clay 30 cm gravel 50 cm soil. Under peg. 150 cm clay

Peg S8. Above peg. 40 cm peat 70 cm very fine peat 100 cm soil Below peg. 130 cm peat. Note: bottom peat bed is rusty.

Peg S7. Above peg. 75 cm peat 90 cm soil Under peg 50 cm peat 80 cm clay Note: peg S7 the bedding of the clay is at a steeper angle than the bedding of the peat. There is an unconformity.

Peg S6. Above peg. 60 cm peat 100 cm soil Under peg. 30 cm peat 95 cm soil.

Peg S5. Under drain pipe Above peg. 35 cm peat 100 cm soil. Below peg. 40 cm peat. 100 cm clay.

Peg S4. Above peg. 25 cm peat. 90 cm soil. Under peg. 62 cm peat. 100 cm clay.

Peg S3. Above peg. 25 cm peat 95 cm soil. Under peg. 27 cm peat 70 cm clay

Peg S2. Above peg. 15 cm peat 110 cm soil Under peg. 32 cm peat 75 cm clay to beach surface

Peg S1. Above peg. 30 cm peat 120 cm soil Under peg. 60 cm peat 130 cm clay to beach surface.

Peg N1. Above peg. 40 cm peat 106 cm soil Below peg. 23 cm peat 141 cm clay

Peg N2. Above peg. 60 cm peat 60 cm soil Below peg. 142 cm clay.

Peg N3. Above peg. 16 cm peat 50 cm soil Below peg. 25 cm peat 135 cm clay.

Peg N4 - Soil 70 cms Peat 60 cms Peg (horizontal datum) Peat 80 cms Black fine peat material 44cms (base not seen)

Peg N5- Soil 80 cms Peat 53 cms Peg Peat 48cms Black fine peat material 49 cms (base not seen)

Peg N6 - Soil 30 cms Peat 80 cms Peg Peat 20cms Black fine peat material 55 cms (base not seen)

Peg N7. Above peg. 55 cm peat 70 cm soil. Under peg. Peat 30 cm 55 cm clay till the visible border.

Peg N8. Above peg. 90 cm peat. 50 cm soil. Under peg. 50 cm peat 30 cm clay

Peg N9. Above peg. 95 cm peat 60 cm soil Under peg. 35 cm peat 35 cm clay to visible border.

Peg N10. Below peg. 25 cm peat 80 cm peaty clay (very fine peat) 20 cm grey clay (exposed) Above peg. 100 cm peat 60 cm soil.

Peg N11. below peg. 90 cm peat to lower edge. 40 cm very fine peat 200 cm grey clay. Above peg. 20 cm peat 100 soil.

Peg N12*. Above peg. 30 cm peat 100 cm soil. Under peg. 30 cm peat. 100 cm yellow soil/clay 220 cm grey clay

Peg N13*. Above peg. 70 cm peat 140 cm yellow soil/clay Under peg. 70 cm peat 312 cm clay.

Peg N14*. Above peg 5 cm clay 60 cm peat 13 cm clay 120 cm soil Below peg. Grey clay below 320 cm

* Note: The measurements on peg 11 till 14 are done 1 metre (100cm) higher than the measurements taken on peg 1 till 10.

Note: we met Local Photographer, Peter Jagger, who told us he had photographing the cliff for the last 30 years and the pictures are in the Hull Local History Centre and some archives were in Hornsea Library. Hornsea Library told Jan that their records had been transferred to the Treasure House in Beverley.

Stuart and Graham revisted the site on 7th July. Graham writes:-

We re-layed the datum line in exactly the same position as before and recorded the following.

Datum line to mouth of gap 8.5m

narrowing of gap 12m

exposed end of pipe in gap 19.6m

front edge of concrete slab at gap entrance 24.3m (cliff top)

square concrete slab behind above 29.5m

post of kissing gate 32m

Yellow pipe to south end of datum line 13.6m.

However, this combined with the other peg readings gives a total length of the datum line of 96.9m when in fact it was 104m. This discrepancy is probably measurement error....

When looking westward on the cliff top, a radio mast is clearly visible on the horizon. On a closer hill, is a well preserved concrete lookout post. We found that when we walked along the cliff the mast "moved" behind the lookout post. When we aligned the mast with the entrance door ,on the left of the lookout post, it closely matched the position of peg N14. The bearing of this transit line was 270degs,ie: due west. So in the future a N-S datum line could be set up on the beach and where the transit line bisects it, could be peg N14 and then further pegs could be placed in the cliff at a bearing of 270 degs from the datum line at, say, 2m intervals along the datum line. This should permit some consistancy in future readings.

 

Graham's GPS readings:-

CLIFF CONTOUR SKIPSEA - GPS READINGS 19/06/2011

Datum line South TA 18405 54579

North TA 18370 54677

Cliff Base contour North to South

TA18363 54677

18368 54665

18374 54659

18370 54652

18374 54645

18372 54643

18373 54634

18381 54630

18369 54625

18383 54622

18383 54611

18403 54579

Cliff Top contour North to South

TA18356 54671

18364 54659

18369 54639

18378 54630

18365 54626

18379 54621

18380 54605

18398 54579

 

 

updated 15/4/2014

Copyright Hull Geological Society