Sills or Dikes

Logging tasks

Message me the cache name, and let me know the group you are logging for if more than one. If you are not logging about the same time people will need to submit their own answers.
Looking up on the hill do the white intrusions in the granite appear to be vertical, horizontal, or both?
Looking at the rock that they are located in, are the cracks between layers, or just running through the stone?
Based on your above answers and the descriptions below, would these be sills or dikes? why?

Sometime 500 million to 4.5 billion years ago lived the Precambrian period. Ok, it did not live, but that is the time frame we are talking about. During that time period magma poured into a large chamber and formed into a huge block. What you see to the northwest is the rock that was formed in that time. A giant pool of granite was formed, then cooled. Eventually it would be covered and then the coverings would erode away.

Yet before the mountain erodes away something happened Eventually the forces of the earth start working on it. The continent moves and shifts. it tries to make the granite rock bend, and eventually the granite stone cracks. Sometimes the rocks break in one large crack. This mountain broke and cracked many times . Then when magma starts melting material and pushing it up, if the pressure is high enough it squeezes into those cracks like a pastry chef filling a creamy doughnut.

More cracks can form, and as these cool we end up with a crisscross pattering in the broken earth.

Sills

Sills form between layers. When layers of material are laid down then the magma squeezes between them they are referred to as a sill. They can be tipped vertical over time or folded but if they form between layers they are referred to as a sill. A comparison may be the layer of frosting between two cake slabs. No matter how you turn it or fold it it is still between two slabs.

Dikes

Dikes squeeze through the cracks in large solid rocks, like the granite above, and can break through many layers of material. Usually moving through at any angle. For example take any cake. cut it in any direction. It may have a sill in it already, but once cut fill it with frosting and push it together. That would be a dike.

Either of these types can be in singles or can have many intrusions.

picture from geology.um.maine.edu