Sideling Hill Slide Show - Md Dept Of Natural Resources - Cc

Welcome to the Sidling Hill exhibit center. Sidling Hill as a unique geologic classroom providing an unusual view into 350 million years of the past. On a clear day. The cut is usually visible about six miles away on high 68 eastbound. And 13 miles away on I-70 westbound and occasionally as much as thirty seven miles away from South Mountain sidling Hill has been a formidable obstacle to travel since the earliest days when settlers were moving west. Prior to the present God travelers crossed the mountain about two miles to the south on us for. The hairpin turn at the top of the mountain was responsible for many accidents. A new group to the west was needed to meet interstate standards and bypass the old hairpin turn. The state highway administration considering a couple of options. One a tunnel. And the other an open road cut. A tunnel was not chosen because of long term maintenance costs and safety concerns. Construction of the open road cut began in 1983 at the mountaintop where you can

see the underbrush has been cleared. It took 16 months to complete the cause over five million pounds of explosives were used in the blasting of the mountain. About four and a half million cubic yards or 10 million tons of rock were excavated and used as built for the inclined road grades up to the cottage from east and west. Some of the rock was then crushed to uniform size and used as aggregate for the road bed itself. Excavation involved a variety of equipment ranging from shock old rigs to bulldozers. To dump trucks. The contractor purchased all new construction equipment which was under warranty to minimize repair delays. A coordinated effort among workers allowed the contractor to finish on schedule and with minimum downtown as work progressed and the cop was exposed.

The Maryland Geological Survey recognized a textbook example of a U-shaped downfall called a syncline survey staff proposed a geological interpretive center to help share geologic information about the science with the citizens of Maryland as well as with all travelers. After excavation was complete the new four lane highway through the cut was completed in August 1985. The finished guide is seven hundred twenty feet wide at the top and 200 feet wide at the base. There are four benches are burned on each side to control a rock wall. They are approximately 10 to 20 feet wide with an 80 foot drop between each bed. In the background is the newly completed four and a half mile section of I 68 and in the foreground is a seven mile section of U.S. 40 which is still in use today as a scenic route with Governor William Donald Schaefer support the State Highway Administration soon began designing the complex which would serve as an

exhibit center a Tourist Information Center and a rest area construction of the pedestrian bridge and parking lot began in the spring of 1989. Construction of the building began in 1990. The building was completed in the summer of 1991. The color and angular shape of the exhibit Center building is intended to mimic the earth tone and sharp angles of the cut itself. It was dedicated by the governor and other state and local officials and opened to the public on August 2nd 1991 on the same day Interstate 68 was dedicated in recognition and memory of those Marylanders who served in the Vietnam War. The memorial plaque is located outside near the entrance to the exhibit center parking lot. The 340 foot deep God helps tell the story of the formation of the Appalachian Mountains.

Although the cut itself offers quite a dramatic view the general visitor may not see what the geologist see is one of the goals of his center in the sky is to help provide the public with a better understanding of the geology of the country. To visualize what you see at the road got a reconstruction of the geologic history. As the geologist would interpret it is shown in a series of three dimensional block diagrams. About 350 million years ago a shallow inland sea covered western Maryland depositing marine sediments in the area around sidling Hill. Gradually rivers flowing from mountains near Baltimore filled in portions of the city with fresh water sediments. Between river banks lush vegetation grew in swamp like environments as shown in green. The majority of fossils found today at sidling Hill originated in this environment. Over time both the Marine and river sediments were cemented or liquefied into rock. Geologists believe that the African continent collided with the North American continent about

two hundred forty five million years ago. This continental collision caused compression and folding of the rocks into a series of folded geologic structures called antique lines and syncline. The a shade folds which look like hills are termed antique lines. Thank A for the shape of an anticlimax. Attic lines tend to erode faster due to water entering the cracks or fractures along the top of each pole. The U-shape folds which look like valleys are called syncline. Think gas for the shape of a sink. Sink lines are usually less fractured thereby eroding more slowly than adjacent attic lines. After more than 200 million years all the volume of sediment shaded in red has been removed by erosion. The net result is the next stage of the erosion. We see today. Here town village yellow on the left is seen as a structural twin's inclined to sidling killing yellow in the center of the block diagram.

Silent Hill remains a ridge today due to the more resistant nature of the capping sandstone. However given sufficient time this ridge too will be eroded. A noticeable feature when you look at the exposure is the ever present water flowing from the sides of the hill. To water bearing zones called aquifers were intercepted by the excavation of the mountain. As the aquifers continuously leak. The a bad break in the water causes iron oxide or rust to be deposited along the sides of the rocks. During the winter months a beautiful ice cascade can be seen as the flowing water freezes. A close up shows the various colors of the eyes depending on the variable mineral content of the freezing waters. We hope that you take the opportunity to visit the building's other levels by stairs or elevator to view our geologic exhibits which include remote sensing imagery of the cut. Also a true scale

model of the cut is available for visually impaired visitors a fiber optics game to test your knowledge of history as part of the transportation on the mezzanine if weather permits. Take a walk outside up the fenced walkway to view the cut and close. Several geologic wayside stations help you interpret what you see. I walk over the pedestrian bridge that has been dedicated to the late state senator Victor Kush which offers good photo opportunities from the middle of the bridge as well as from the opposite side south of the road. The sidling Hill exhibit center is operated by the Maryland Department of Natural Resources state forest and Park Service and the Maryland Department of Transportation State Highway Administration. Operating powers vary depending upon season and are posted outside the building. Rest rooms are open 24 hours a day. Except for the fenced walkway to the observation area. The site is fully accessible to wheelchairs and visually impaired citizens. If you have any

questions members of the staff at the information desk will be happy to help you. Before we close we invite you to return during different seasons of the year to enjoy the natural beauty of Western Maryland. Thank you for visiting us.