Archive for the ‘Geology’ Category

purple sand

A lot of people wonder why the sand at Plum island is purple. When we went on the field trip that was the first thing i was thinking about. The sand contains Garnet grains which is what makes the sand purple. The name “garnet” comes from the word, “granatum,” which means “a pomegranite,” for the mineral’s resemblance to the red seeds of the pomegranite fruit. Garnet sand can be any colors from pink to red to even light orange. The garnet sand is only located in three places, Plum Island beach sands, Woodruff Pond sand in the Adirondack Mountains, and Woodruff pond.

Quartz, which is a mineral composed of silicon, is similar to Garnet sand and also causes sand to be purple. Quartz is a variety of clear colors, including white, rose, and purple. Quartz is known as one of the most common components and is a major reason why the sand is purple. Quartz is not in the sand at Plum Island but it is a another component other than Garnet, which is at Plumb Island, that causes sand to be purple.

Theres really only one reason that the sand is purple and that reason is that it contains Garnet grain in it which is not very common. This makes the sand purple because it is a pomegranet color causing the sand at Plum Island to be purple. The sand is very pretty and many think its really odd that its purple but it just contains a certain mineral that others dont.

Read Full Post »

In oceanograghy so far we learned about lots of things; sediments, ocean tides, etc. But the one that intrigued me the most was the Glacial Activity we did during the field trip last Friday. It was very interesting to learn about it, as long as eratics, etc.

Glacials are made during Glacial periods; an intervak of time during an ice age marked by cold temperatures. Glacials are made when cold temperatures freeze the ice, and form a big “ice cube”. Glacials were very common during ice ages. The Glacials picked up sediments and collected them over a period of time.

After the ice age, the Glacials that picked up a lot of sediments turned into a rock which is living proof of glacials. Eratics are another name for Glacials as well. Which means they are erratic.

On the field trip we stopped by an erratic that was located in my home town, Groveland. It is a large four sided erratic, that is approximaently 25ft tall. It is said to be an awesome place to pratice rock climbing.

However, the erratic, Stickneys boulder wasnt always located in Groveland, MA. It traveled all the way from Canada. That means, during the ice age, the glacial started in canda and along the way picked up sedimetns and ended up as a awesome erratic that landed in Groveland.

I found this to be the most interesting thing i have learned so far in Oceanography because it was neat to learn about Glacials that turn into erratics. Also, because its fascinating to have something that was originally formed during the ice age still stand today. It took my interest because it is neat because it is in my hometown, and marks a part of history that i knew little about. After learning about Glacials, and Stickneys boulders I learned a little information that i didnt know before!

Read Full Post »