Between a Rock and a Hard Place

Between a Rock and a Hard Place

Coral, wanted dead and alive; a brief excursion into the world of coral science



Today we have a guest post from Dr. Peter Tomiak who delves into the life and death of corals…

I completed my undergraduate degree in Biology and Geology at the  University of Bristol in 2008. Subsequently I undertook a sponsored internship with Save The Elephants, in Samburu National Park Kenya, before starting a short term position alongside Prof. Adrian Lister at the Natural History Museum, London, constructing a database of radiocarbon dates for extinct Pleistocene mammals. At this point I moved away from terrestrial mammals, and into the marine realm. I completed my PhD, examining the nature and applications of coral skeleton, within the Earth Sciences Department at Bristol University  in 2013 (funded by the Natural Environmental Research Council and an additional Wingate Scholarship), and then continued with my research as a postdoctoral researcher at the university into 2014. Over the past 6 months, I have been travelling throughout South and North America, performing volunteer work at several State and National Parks along the way. I enjoy spending time in the natural environment and am very enthusiastic about conservation. In my spare time, I enjoy wildlife photography, SCUBA, live music and playing or watching football. [Read More]

Plastic packaging – a horror film

Zero Waste Week is an opportunity to reduce landfill waste & save money. In its seventh year, the week runs 1st – 7th September 2014. The theme is “One More Thing” – what one more thing could YOU do? Find out more at or on Twitter using #zerowasteweek

Ever since I spent a summer working on a landfill site, I think twice before putting any items of rubbish in the bin.

Yanley Landfill

Yanley Landfill site, south Bristol, during the Balloon Fiesta in 2007. The site is now closed and is being restored to woodland. Photo credit: Charly Stamper

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Science snap (#31): Mammatus clouds

After all the thunderous weather this weekend and being British, I thought I’d do a weather themed science snap. Don’t bolt yet; it’s a volcanic-weather themed!

Volcanic mammatus clouds forming after the eruption at Mount St. Helens. Copyright: Douglass Miller

Volcanic mammatus clouds forming after the eruption at Mount St. Helens. Copyright: Douglass Miller

This is a picture of mammatus clouds following the eruption of Mount St. Helens in 1980. These clouds are pretty rare, unusual and distinctive. Formally, the Glossary of Meteorology defines mammatus clouds as “hanging protuberances, like pouches, on the undersurface of a cloud”. The definition is aptly descriptive, but in essence mammatus are a series of bulges at the base of clouds, often under large thunderous cumulonimbus clouds. There are many different types of mammatus clouds, each with distinct properties and occurring under various cloud types, and mammatus in volcanic clouds is just one subcategory. There are relatively few documented occurrences of Mammatus under volcanic clouds. Apart from Mount St. Helen’s, they’ve been observed at during the eruption of Mount St. Augustine on 27–31 March 1986 and Mount Redoubt on 21 April 1990. No generally accepted formation for these mechanism exists, however it is clear that a sharp temperature gradient and a wind shear across the cloud-air boundary is needed to create these clouds. Did anyone spot Mammatus clouds in the UK this weekend?

Science snap (#30): Aust Cliff, Gloucestershire

One of the most fascinating things about geology is its ability to reveal global events from evidence contained within a single outcrop. The cliff exposure at Aust in Gloucestershire, UK, is a spectacularly colourful example of this.

Located beneath the original Severn Bridge, and running alongside the Severn Estuary, the 40m tall rock face records the drowning of an ancient desert by rising sea levels. In the Triassic, the SW of England sat 30ºN of the equator (the position of modern-day northern Africa). As the supercontinent Pangea rifted apart, the land was flooded by Jurassic oceans.

Aust cliff, near the Severn Bridge in south Gloucestershire. Photo credit: Charly Stamper

Aust cliff, near the Severn Bridge in south Gloucestershire. The change from red to grey-green in the rock strata records the flooding of an ancient desert by rising Jurassic seas. Photo credit: Charly Stamper

The red beds of the Triassic Mercia Mudstone group (~220 millions years old) form the base of the cliff, a geological archive of a time when this part of the UK was a hot, subterranean landscape. Rounded quartz grains with haematite coatings and accompanying veins of gypsum and celestine testify to an arid, windswept desert scattered with ephemeral lakes and playas.

The sudden change to the grey-green strata of the Blue Anchor formation is immediately evident to the eye. These clay-rich silty rocks contain halite crystals and provide evidence for the gradual ingress of inter-tidal lagoons and brackish lakes conditions.

Further sea level rise is charted by the Westbury formation (~205 million years old). The basal section comprises the famous Westbury Bone Bed, noted for yielding fossil insects, plesiosaur teeth and abundant bivalves; above this lies a layer of Cotham Marble, rich in stromatolites.

The Severn Bridge is easy to get to by bike – follow National Cycle Routes 4 and 41 from Bristol. Access to the cliff is via a steel gate to concrete causeway, at the bottom of the hill from Aust village.

The exposure at Aust is a SSSI; please only collect fossils from cliff debris and be careful of falling blocks close to the rock face.