Natural Bridge State Park is a day use facility, open from Memorial Day through Columbus day each year. Park hours are from 9:00am to 5:00pm, 7 days a week. A fee of $2.00 per vehicle is charged to help defray the cost of maintaining and staffing the park
The origins of the Marble Bedrock found at Natural Bridge State park began with the Deposition of lime oozes during the Cambian and early part of the Ordovician geologic periods, roughly from 550 million years ago up to about 470 million years ago. The oozes built up thick layers of sediments on the sea floor; then the great weight of the sediments lithified the lower layers into limestone, a sedimentary rock.
The creation of limestone was followed by two periods of orogeny– or mountain building – which involved the collision of the Tectonic plates of the earths crust. The Taconic orogeny began about 460 million years ago when a fracture formed in the sea floor to the cast of the area, resulting in one part of the sea floor over-riding the other and colliding with an uplifted area now exposed along the face of the Hoosac Mountain. This collision threw up a great range of mountains in the Berkshires, called the ancient Taconic Mountains by geologists, the limestone buried deep in the heart of these mountains were subjected to tremendous pressures and high temperatures which altered, or metamorphosed, them into marbles, a metamorphic rock.
The Taconic orogeny was followed by a period of erosion, during which the sixteen thousand to twenty thousand foot peaks of the ancient Taconic Mountains began to erode away. But then, about four hundred million years ago, the Acadian orogeny began. This orogeny involved the closing of the Ancient Sea, as the North West coast of Africa converged with North America in the New England region. This collision renewed uplift in the Taconic Mountains – and caused further heat and pressure, which brought the marbles up to their present highly crystalline condition. When the Acadian orogeny ended 350 million years ago, the ancient Taconic mountains were once again 16-20 thousand feet high; and they span an area from the modern day New York- Massachusetts border to the Connecticut river valley, (which did not exist back then) and stretch from Northern Vermont South to the middle of Western Connecticut. The marbles we see at Natural Bridge state park were then buried deep within the heart of the mountains, 5 to 7 miles deep (Which we know from studies of the depths at which rocks must be buried to be metamorphosed to the high grade we see in the marble at Natural Bridge today).
Since the end of the Acadian orogeny 350 million years ago, the ancient Taconic Mountains have been eroding down. There were no more great upheavals in New England to renew uplift. The result has been the mountains have eroded down into their “roots”.
As the great weight of the peaks was removed, the underlying crust was able rise up slowly, bringing deeper and deeper rocks closer and closer to the surface. This is possible in geologic terms because the underlying layer of the planet, called the mantle, is plastic inconsistency. A mountain range will press the crust into the mantle, and when the mountains erode away, their weight being removed, the crust will slowly rise again. Thus we now see marbles which were created deep in the earth exposed at the surface today.
Even though the area had been known to the Mohawk Indians (Native Americans) well before the Europeans, it wasn’t until its description by a hunter by the name of Seth Hudson, working for Fort Massachusetts in the 1700’s, that the area became known to everyone. It is because of his description of the area, the brook flowing under the Natural Bridge bears his name “Hudson Brook”. It wasn’t until 1810, that the value of Natural Bridge Marble was recognized as a building material, and soon afterwards quarrying began. In the early days of operation, the quarry was run by many different entities and stone cutting shops. They produced everything from window sills, thresholds, door steps, flagging, building foundations, as well as marble for monuments, and gravestones.
In 1837, with the growth of popular demand for marble, Wm. McAuley, began the first regular operations of mining the marble. It wasn’t until the 1850’s that steam engines became available to the miners. Before the steam engines were in use, the miners and workshops relied heavily on hydraulic power (the use of water run machinery).
Then in 1890, The Hoosac Mine Company bought the mine and began its operations until its sale in 1945 to Micro-White Company, a New York based Business.
During the time of the Hoosac Mine Companies run, they built a 3 story facility to house there operations. There they produced a wide variety of bi-products that included poultry grit, powder for toothpaste, face paint, and other items along with there main stone products. In 1947 the entire mine operations suffered a great loss which led to its permanent closing.
A fire of unknown origin completely destroyed the mill causing over $20,000 in damages. Because of the great cost of rebuilding and updating, it was decided to end all operations of mining.
The area was then sold to Edward Elder an amateur geologist. Recognizing its importance as a National Natural Historical area, he maintained it as a tourist attraction until his death in 1984. During his ownership, he charged a $1.00 admission fee for a guided tour the area, and tell you anything about the geology and history of the area that you may have had. He spent countless hours clearing out much of the rubble and shrubs that were in the area, as well as building a series of walkways and catapults that allowed tourists to view the natural beauty of this wonderful area.
In 1985, the Massachusetts Department of Environmental Management purchased the property from Edward Elders widow in order to maintain the site as a state owned property, and to continue the sharing of the natural beauty that Edward Elder had strived for during his ownership.
To log this Earth Cache please click on "Message this owner" at the top of the page and answer the following questions.
1) The quarry men extracted the marble using a technique called what?
2) The Blasting Rock was used for what? (It is NOT for them to work on. it is used for something else)
3) What 2 things were done if a marble slab was two big to move?
As with all EarthCaches, please do not post any pictures that will give away any of the answers.
During construction, just answer any questions you can.