One woman's quest for geological understanding!

September 2015Monthly Archives

“Officially” a PhD Student at Keele University!

logoYesterday, I went to enroll at Keele University, for a PhD in Earth Sciences!

I have collected my Keele Card (how technology has improved – I can even use it in the shops!), my NUS card, and (thanks to their IT services putting up with my ridiculous lack of technological knowledge) am now connected to the Keele wireless internet!

Monday brings the “important” stuff – finding my way around, exploring a little more, and finding out where on Earth (like the pun?) to start!

Until then, please enjoy these photos I took, on what was a glorious autumnal day!

2015-09-26 10.42.57 Continue reading »

Further investigation along the Marston Canal, Northwich

Background:

Following on from the geophysical fieldwork conducted on the 27th and 28th July 2015 (microgravity), further investigation into the possibility of:

  • brine influx from any “leak” through to nearby mines
  • changes in depth in the canal due to subsidence

was proposed.

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Geophysics training: (time-lapse) micro-gravity survey along the Marston canal, Northwich, Cheshire

Subsidence as a result of mining in the UK (and abroad) has occurred throughout history. This varies in severity, with evidence of subsidence ranging from topographic depressions to catastrophic surface collapse. In Northwich, and the surrounding areas, the long history of Salt mining and brine pumping has taken its toll. In order to detect / characterise / monitor areas (susceptible) of subsidence, a combination of remote sensing and near-surface geophysics can be applied.

Jamie Pringle and his team at Keele university have conducted much research and monitoring around the Marston Canal over more than 20 years (Pringle, Styles et al. 2012)

“In the village of Marston, the Trent and Mersey Canal crosses several abandoned salt mine workings and previously subsiding areas, the canal being breached by a catastrophic subsidence event in 1953. This canal section is the focus of a long-term monitoring study by conventional geotechnical topographic and microgravity surveys. Results of 20 years of topographic time-lapse surveys indicate specific areas of local subsidence that could not be predicted by available site and mine abandonment plan and shaft data. Subsidence has subsequently necessitated four phases of temporary canal bank remediation. Ten years of microgravity time-lapse data have recorded major deepening negative anomalies in specific sections that correlate with topographic data. Gravity 2D modelling using available site data found upwardly propagating voids, and associated collapse material produced a good match with observed microgravity data. Intrusive investigations have confirmed a void at the major anomaly. The advantages of undertaking such long-term studies for near-surface geophysicists, geotechnical engineers, and researchers working in other application areas are discussed.” (Pringle, Styles et al. 2012)

The fieldwork which was conducted, is a continuation of Jamie’s research.

Fieldwork

Fieldwork was conducted 27/7/15 & 28/7/15 along the Marston Canal, in the Survey area indicated in Figure 1.

Figure 1. Location map of survey area: Marston, Northwich.

 

Aim

Monitor and measure relict salt mines using geophysical methods

Objectives

  • Become familiar with measuring micro-gravity geophysical data using a Scintrex CG-5 micro-gravity meter, Leica Pinpoint R100 and Prism and pole.
  • Survey data collection area, where gravity points are taken
  • Conduct a survey

Continue reading »