Here's a breakdown:
* Specific Gravity: This is the ratio of the density of a substance to the density of water at 4°C. It's a way to compare the relative density of different materials.
* Rock Composition: Rocks are made of minerals, and different minerals have different densities. For example, quartz is denser than feldspar.
* Porosity: The amount of empty space within a rock also affects its density. Rocks with more pores have a lower density.
General Ranges for Specific Gravity of Rocks:
* Igneous Rocks: 2.5 to 3.5
* Sedimentary Rocks: 2.0 to 3.0
* Metamorphic Rocks: 2.5 to 3.5
Examples:
* Granite: 2.6 to 2.8
* Basalt: 2.9 to 3.0
* Limestone: 2.5 to 2.7
* Marble: 2.6 to 2.8
Determining Specific Gravity:
To find the specific gravity of a particular rock, you'd need to use the following steps:
1. Weigh the rock in air.
2. Weigh the rock submerged in water.
3. Calculate the specific gravity using the formula:
```
Specific Gravity = (Weight in air) / (Weight in air - Weight in water)
```
Note: The specific gravity of a rock can vary within a given rock type due to its composition and other factors.
