Geology is the study of the Earth; its rocks; its structure; everything within it - and also the processes that shape its surface. Forensics is the use of science and technology to investigate and establish facts. Geologists, and especially palaeontologists, use the evidence found in rocks to deduce the environment that a sedimentary rock or fossil was deposited in, or the 'story' of how the crystals in a metamorphic or igneous rock formed.
As stated, there are three main types of rock:
1 – Igneous Rocks
These form when molten rock (known as ‘magma’), cools. As a general rule, the slower it cools, the larger the crystals found within it, and vice versa.
Common examples include:
Granites form when a specific type of molten magma is intruded into the outer solid layer of our Earth (the ‘crust’). Taking tens of millions of years to happen, the magma eventually cools very slowly underground, forming generally larger (>1cm) crystals, giving some quite pretty textures. Granites typically have a paler overall colour, varying in colour from overall red, to grey, to brown, to black in colour, depending upon the minerals the specific granite is comprised of. Granites can easily withstand the forces of erosion and weathering, so often look very ‘new’, despite being exposed by humans for thousands of years, hence why they are chosen for their desired purposes.
Gabbro also cools underground over millions of years, also resulting in larger crystals, but is made from a different composition of magma, resulting in a much overall darker colour than granite.
Basalts are formed by the same magma that makes gabbros being extruded as lava at the Earth’s surface from a volcano, so cools quickly, forming small crystals.
Obsidian is formed in the same way as basalt, but cools very rapidly, forming microscopic crystals, giving a glassy appearance.
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2 – Sedimentary Rocks
These form when older rocks have been weathered and eroded, then transported, and then deposited, usually in layers.
Individual layers can often show evidence of what happened at the ancient surfaces; footprints, worm trails, ripple marks (created by waves lapping the shore), and many other such features (including the presence of fossils), can all help us deduce the actual environment the layers were deposited in (for example, in a shallow sea, on a dry and windy desert, in a massive forest, etc.).
Over time, these layers are then squashed by the weight of overlying sediments, slowly turning the sediments and anything within them into sedimentary rocks.
Common examples include:
Mudstone - this rock is determined by the size of the ‘grain’ in the rocks (‘mud’ being a smaller grain size than ‘sand’). The mud could have originally been deposited on land (in rivers or lakes, etc), or in the sea.
Sandstone - again, this rock is determined by the size of the ‘grain’ in the rock, it having a ‘sand-sized’ grain size. Sandstones can be formed in variety of locations, from the massive, cross-bedded dunes that are blown around hot, arid deserts, to the sand banks deposited in streams and rivers, or where rivers enter a lake or the sea. Alternatively, the sand could be deposited in deeper sea environments.
Limestone – generally formed in ancient warmer, shallow seas (e.g. like the present day barrier reef off NE Australia), these can be formed around beautiful coral reefs, where fish, snails, worms, and various shells all lived, inter-acting with each other as a community, living in and on the mud and sand that made up the ancient sea-floor.
Coal – formed in ancient (up to 300 million year old!) swamps, full of massive trees and ferns.
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3 – Metamorphic Rocks
These form when older rocks are buried deep within the Earth’s crust over millions of years, squashing and heating the rocks, so deforming them and causing the original structure within the rock to crystalise or re-crystalise, depending on the original rock. Common examples include:
Marble – formed when ancient limestones are crystalised, destroying the delicate fossils that may have been present, often giving the rock a ‘sugary’ appearance. Marble can be in any colour, but commonly white/pale marble is used in statues in the local area.
Slate – formed when ancient mudstones are crystalised, squashing the mud grains together, then turning these grains into flatter minerals, all elongated in the same direction, so giving slate its characteristic property of being about to be easily split (e.g. for roof tiles)
Schist – formed when slate is further deformed, causing the already-elongated minerals to grow larger and more prominent
Gneiss (pronounced ‘nice’) – formed when schist is further deformed, causing the already-elongated minerals to grow even larger still, giving the rock a ‘banded’ appearance.
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As usual with EarthCaches there is no physical cache. To log this EarthCache, the cacher is required to study the COPP Memorial, answer a few simple questions, then email the answers to the questions below:
The ‘Combined Operations Pilotage Parties’ (or ‘COPP’) were dedicated teams trained in covert operations, reconnoitring beaches selected for landings on enemy occupied territory throughout the world during World War 2. Their formation in 1942 followed a disastrous raid in Dieppe in 1942, after which, Lord Louis Mountbatten, Chief of Combined Operations, ordered the formal establishment of the COPP unit. The Unit of less than 200 men went on to win over 90 medals and commendations in a little under three years. Their work was vital to the success of the D-Day landings, but was typical of the exploits of other COPP teams operating throughout the world. The link with Hayling Island is that the top secret COPP Depot was set up on the island in 1943 under the instruction of Lord Mountbatten, this being the base for the small teams of sailors and soldiers who were all trained as frogmen and canoeists for covert beach reconnaissance and other essential clandestine operations.
The memorial stone was dedicated by Countess Mountbatten to the COPP Heroes on 27th September 2012 in a ceremony attended by surviving COPPists and their family and friends, representatives of the army and marines, the Mayor of Havant, hardworking committee members of COPP Heroes, local people and the media, and is a fitting tribute to the very brave men of COPP.
The COPP Memorial stands adjacent to a gravel path that runs parallel to the sea front and nearby mini-railway. Wheelchairs and strollers can easily be wheeled along this path. Wheelchair users may not be able to touch the Memorial, as it is surrounded by a grass slope, but should be able to see the required features so as to answer the set questions as given below.
Please go to the Memorial and study the stone and the surrounding information boards and plaques.
Q1. The rock that was used to make the Memorial – is it made of grains or crystals?
Q2. How big, what size, and what colour are the answer to the dominant ‘parts’ that you gave as your answer to Q1?
Q3. What rock do you conclude this Memorial was carved from?
Q4. If you were to look down from above at the Memorial, what shape outline would it present?
Q5. Please add a photograph of yourself/your GPS etc., taken at GZ, but the photo NOT giving away any answers.
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Once you have all the information for the above Tasks and questions, please send me your answers via email or through the Message Centre before logging your visit. I endeavour to respond ASAP, however if I have not within 48 hours, please do email again. I do read every communication I receive, and will delete Logs that do not have a matching set of answers and/or do not adequately answer the set Tasks.
Any Logs without the required photo will be deleted without warning. Group Logs will not be accepted and will also have Logs deleted without notice.
Please feel free to add photos with your log, but please, do not post any photos that give away any of the answers, thank you.