1.4. Layering of Lava Flows

Like now what you see here is a kind of lava where we talk about the ‘Aa’ which is the basaltic lava which is characterized by a rough or a rubbly surface and these lava blocks also we actually extract the clinker from this kind of rough and rubbly surface lava is called ‘Aa’. This is a very smooth surface which is unbroken lava is also a basaltic lava that has a very smooth, billowy, undulating or a ropy surface and this is called a Pahoehoe...

This chunk describes the two main types of basaltic lava flows: 'Aa' and 'Pahoehoe'. 'Aa' is noted for its rough texture and fragmented surface, making it jagged and sharp. It often breaks apart when cooled. In contrast, 'Pahoehoe' has a smooth, ropy texture, appearing more fluid and unbroken, resembling flowing mercury. Understanding these two types helps in predicting the behavior of lava during volcanic eruptions and its impact on the landscape.

Think of 'Aa' lava as a piece of crumbled chocolate bar—uneven and hard to navigate over. Now, visualize 'Pahoehoe' lava as a silky chocolate fondue that flows easily and smoothly. Just as you would walk differently over a crumbled bar versus a smooth surface, the landscape formation also changes based on the type of lava flow.

Now, what we can see is the layers of the horizontal layers of one over the another. So, these layers also talks about these beds which are talking about, so a set of lava have come down and gradually another set of lava and the by the time it cools down the another set came, another set came...

This chunk explains the process of lava flow layering. When a volcanic eruption occurs, lava flows out and spreads over the ground. As this lava cools, it solidifies and forms a layer. When subsequent eruptions happen, new layers of lava are deposited on top of the previously cooled lava. Over time, this creates a stack or sequence of horizontal layers that represent different volcanic events, allowing geologists to study the history of volcanic activity.

You can think of this layering like a stack of pancakes. Each time you pour batter onto the griddle, it spreads out and cooks, forming a layer. When you add more batter, it goes on top of the cooked pancake, and the process continues. Just like with pancakes, each lava flow adds its layer, which contributes to the overall 'stack' of geological history.

And this Tacheletic Basalt which is not a conducive rock for cave excavation as its chemical properties react sharply with moisture and disintegrate into pieces...

This chunk highlights the challenges of excavating caves in Tacheletic Basalt. This type of basalt responds poorly to moisture; it can react chemically and break down easily, leading to structural instability during excavation. As a consequence, efforts to excavate or study these areas can be hampered because the rock disintegrates as soon as mechanical forces are applied.

Imagine trying to dig a hole in a soggy sponge. Just as applying pressure will cause the sponge to break apart more easily, excavating in Tacheletic Basalt becomes problematic because the rock crumbles under stress, similar to how wet materials can be difficult to handle.

And you can see also as time passes on the spheroidal weathering takes place because this layers on the top layers keeps coming like a chip by chip and this is again in a spheroidal manner...

This chunk discusses 'spheroidal weathering', which occurs as outer layers of rock gradually erode, causing the underlying layers to become rounded and shaped like a sphere. This process happens over long periods as water seeps into the cracks, leading to further decomposition of rock material. The gradual chipping away of layers can leave the underlying structure more visible or alter the rock's shape into more rounded features.

Picture an onion being peeled away layer by layer. As you remove the outer layers, the core of the onion becomes more exposed and rounded. Similarly, as the outer rock layers get weathered away, the core shape alters to a smoother, more spherical form.

Now, what they did was the archaeologists team they have actually mapped down, they have actually documented the whole set of caves including the analysis of the cracks...

This chunk describes the systematic approach taken by archaeologists to map caves and analyze their structural integrity. By classifying cracks in different categories based on stability, they can identify potential risks in the cave structures. This mapping is essential for preservation and understanding how environmental factors like seepage affect the caves over time.

Think of this as a medical check-up for ancient structures. Just as doctors evaluate health by examining symptoms and classifying risks, geologists assess the stability of caves to ensure they remain safe and intact for future generations, allowing us to learn from our past.

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