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You are currently here: Home > Fossil Locations > Scotland > River Brora |
In partnership with JuniorGeo |
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Introduction
The River Brora provides an isolated exposure of Middle Jurassic rock along its banks, approximately one mile inland from the river mouth. Accessibility is dependent on the prevailing weather conditions; during periods of sustained wet weather the water depth and flow makes viewing or collecting fossils difficult and potentially dangerous.
Please also note that this location has been designated a Site of Special Scientific Interest (SSSI), which means it's illegal to hammer or collect in situ fossils from the river-cliff (see details below); fossil collecting is permitted from the boulders at the river side, down stream of the exposures described.
The nature of the terrain and exposures means the River Brora is best enjoyed by experienced collectors and/or the scientific community; it's less suitable for families or inexperienced collectors for much of the year.
(Left) Limited roadside parking is available with permission from the farm. (Right) Access to the river is made along a narrow track leading from the road.
Access to the river is made along a narrow road running along the north side of the river; a small track (see above-right) leads to the exposure river banks.
The geology of the River Brora
The rocks exposed along the Brora river date from the later part of Middle Jurassic, specifically the Callovian stage 164.7 ± 4.0 to 161.2 ± 4.0 million years ago. The presence of Ammonites and drift wood indicates the sediment was formed within a marine environment, close to the land.
Where to look for fossils?
The erosive forces of the River Brora have exposed a relatively small stretch of Jurassic rock, rich in fossils, along its northern flank, approximately one mile inland of the river mouth. The photos below show the river during a period of relatively dry conditions, at which time the water level and flow are sufficiently low to examine the exposures.
(Left) The loose boulders provide the best opportunity to collect fossils. (Right) The eroded river bank provides an opportunity to examine (not collect) fossils.
Due to it's SSSI status, fossil collecting is not permitted from the exposures themselves (see photos above); however visitors can still observe a number of Belemnite guards protruding from the eroded surface.
The best place to collect fossils is down stream of the exposures, from the boulders on the river bank and within the shallows (see photos below).
(Left) Collecting fossils from a river boulder, down-stream of the exposures. (Right) A hammer and chisel are needed to split loose rocks.
A hammer and chisel provide the best opportunity for extracting specimens, many of which are clearly visible on the boulder surfaces.
What fossils might you find?
The most common fossils (worth retrieving) are Belemnite guards and Ammonite shells, although the latter are often poorly preserved. The photos below provide a snapshot of the type of specimens encountered during a typical visit.
(Left) Ammonite - Binatisphinctes? - exhibiting a reflective blue tint. (Right) A squashed ammonite - Kosmoceras duncani - on the surface of a boulder.
The Ammonites at Brora are poorly preserved, often barely distinguishable from the surrounding matrix (above-left) or squashed (above-right). The Belemnites guards on the other hand are well preserved and can be collected with ease; specimens range from just a few centimeters to over 20cm as shown in the photo below-right.
(Left) A second squashed ammonite - Kosmoceras duncani - on the surface of a boulder. (Right) A large and nearly intact Belemnite within a split boulder.
Other common fossils include pieces of wood (below-right), which provide evidence that these sediments were deposited in close proximity to the land; in most instances fossils provide enjoyment for the context they add, rather than their collectability!
(Left) A small, complete Belemnite on the surface of a river boulder. (Right) A fragment of wood.
Protecting your finds
It's important to spend some time considering the best way to protect your finds onsite, in transit, on display and in storage. Prior to your visit, consider the equipment and accessories you're likely to need, as these will differ depending on the type of rock, terrain and prevailing weather conditions.
(Left) Fossil wrapped in newspaper, ready for transport. (Right) A small compartment box containing cotton wool is ideal for separating delicate specimens.
When you discover a fossil, examine the surrounding matrix (rock) and consider how best to remove the specimen without breaking it; patience and consideration are key. The aim of extraction is to remove the specimen with some of the matrix attached, as this will provide added protection during transit and future handling; sometimes breaks are unavoidable, but with care you should be able to extract most specimens intact. In the event of breakage, carefully gather all the pieces together, as in most cases repairs can be made at a later time...continued.
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