This is an EarthCache. There is no container at the coordinates. In order to log this EarthCache as found, you will need to read the information provided below, make some observations at GZ, send the answers to the following questions to me, and then log your find with a photo of your caching name or yourself at GZ.
Please remember these logging questions as you read the EarthCache lesson which follows:
1. What sort of rock has been used for carving names on the memorial and why (South West face which commemorates the names of the fallen)?
2. What sort of rock has been used for the main body of the memorial and why (this is the tall central body of rock which forms the bulk of this memorial)?
3. Consider if these two rocks have suffered from erosion. Why is this worse for one than the other, and what may have caused this?
4. There is a metal plaque on the North East column (closest to the mini roundabout) which starts "THIS TABLET". What is the last date on this plaque?
5. Take a photo of the memorial including either your caching name on paper, or yourself, and post this photo with your log
EarthCache lesson
This EarthCache lesson will consider the properties and characteristics of different types of rock. These properties mean that some rocks are better suited for some applications than others.
There are four types of rock which have been used in the Chippenham war memorial: a local Limestone, Granite, Marble and Slate. These types of rock were originally formed in different ways: Limestone is one example of Sedimentary rock, Granite is Igneous rock, and both Marble and Slate are Metaphophic rock.
Types of rock in this memorial
Limestone
Limestone is a type of Sedimentary rock which is frequently created by the skeltons of (once) living organisms and it is sometimes possible to see fossils within the rock. Sedimentary rock is created by an accumulation (also known as a sediment) of mineral and / or organic material which has later been cemented together by minerals, over millions of years. Limestone has a high ph which means it has a high alkalinity.
Limestone is strong, so is useful for load-bearing applications. However, it is also soft and porous which can lead to erosion, and erosion can lead to the softening of edges. This loss of detail makes Limestone less useful for retaining any carved details. It's porous nature can also result in staining. Typically limestone is cheaper than many other types of higher value rock, especially if it is quarried locally which reduces transport costs.
Granite
Granite is an Igneous rock, which means it was formed from Magma or melted rock deep inside the Earth, and subsequently exposed to the surface by uplift, erosion, and quarrying. As the liquid rock cools, it crystallizes into solid rock which is made up of three main minerals: quartz, feldspar, and mica. It generally has a speckled appearance and naturally occurs in a mixture of colours which can have higher tones of reds and greys, which make it very attractive. Granite's properties include being very hard and inert such that it can be polished for a high quality brilliant finish. Granite is durable and combined with it's strength, it can bear substantial loads and is resistant to erosion. However the hardness makes it difficult to carve. These properties can make Granites highly desirable (consider the market in kitchen worktops) and therefore Granites can be expensive, and the high density results in higher weight and higher transport costs for an equivalent volume of a less dense rock.
Marble
Marble is a form of Metamorphic rock. Metamophic rock could have originally been anything else, i.e. igneous, sedimentary or earlier metamorphic rock. It has been changed from its original form by high pressure, heat or hot mineral-rich liquids (and often a combination of these). These high energy physical processes invariably result in eradication of any fossils which were in it's original form. In the particular case of Marble, it was originally a Limestone, and when converted into Marble, often has colours and veins which (when polished) reflect light in attractive ways. It is durable and long lasting. Of particular relevance for monuments and artwork, Marble is relatively soft when first quarried and becomes harder over time, which offers opportunities to initially shape the material, which then becomes harder. Marble is porous so easily stained. Marble is a relatively expensive form of rock.
Slate
Slate was originally Mudstone, Shale or Basalt which has been changed by a Metaphophic process at relatively low pressures / temperatures. It is fine-grained and particles have aligned in parallel directions, resulting in Slate being strong in some directions but also brittle and easy to break if force is applied in other directions. It is relatively resistant to scratches, impervious to water and can be split along planes to create thin sheets, which makes it popular for roof tiling and building material. Slate can be relatively soft but can accept fine detail, making it a popular material to carve for artists. Slate is relatively expensive to quarry due to its fragile nature. In addition, because it is a dense rock, it is heavy and more expensive to transport.
Rock types
Here are some photos of the rock types described above (although not necessarily in the same order!
Erosion
There are a number of different causes of erosion which can result in damage to the memorial. This section of the EarthCache lesson considers erosion which could apply to rock in this sort of location.
Erosion falls into two types: Chemical and Physical. These are described in more detail below.
Chemical erosion
Chemical erosion happens if the chemical composition of the rock is changed. Relevant examples are that if a rock is naturally alkaine and it comes into contact with acids (even mild acid) then some minerals within that rock can dissolve. Acid rain is rainwater which contains a mild acid. This can result from dissolved Carbon Dioxide (exhaled by all living organisms) or dissolved pollutants such as Sulphur Dioxide and Nitrogen Oxides (for example, those generated by internal combustion engines powering most cars and lorries).
Physical erosion
Physical erosion is the change in a material without a change in its chemicial composition. Physical erosion often causes rocks to become smaller or smoother. Examples include
- tiny particles of grit being blown against a surface by wind, which become worse in dust storms
- water particles inside rock expanding when they freeze resulting in cracks and damage (water expands when it becomes solid ice, which is why ice floats),
- plant growth can result in roots growing into cracks and forcing them apart
- splash erosion is the impact of a raindrop which can throw tiny soil particles up to 0.6m away
- wave erosion caused by ocean waves crashing against shoreline
- ice erosion, usually glacial, carving through landscapes
- rivers cutting their way through landscapes
- tectonic movement, which can create mountains and seas
Questions to answer
Please answer the following questions in order to qualify for a find. You should send your answers to questions 1, 2, 3 and 4 to me using messaging. Your photo (question 5) should be attached to your log:
1. What sort of rock has been used for carving names on the memorial and why (South West face which commemorates the names of the fallen)?
2. What sort of rock has been used for the main body of the memorial and why (this is the tall central body of rock which forms the bulk of this memorial)?
3. Consider if these two rocks have suffered from erosion. Why is this worse for one than the other, and what may have caused this?
4. There is a metal plaque on the North East column (closest to the mini roundabout) which starts "THIS TABLET". What is the last date on this plaque?
5. Take a photo of the memorial WHICH INCLUDES either your caching name on paper, or yourself, and post this photo with your log
War Memorial series information
If anybody would like to expand to this series please do, I would just ask that you could let Just-Us-Two know first at justustwo1013@gmail.com so they can keep track of the memorial numbers and names to avoid any duplication.