This is an Earthcache. There is no physical container at the posted coordinates, but rather a geological lesson for you to explore. Please review the information on the cache page, then make your way to Ground Zero to make your observations and answer the three questions below. Email your answers to the cache owner by clicking the "message this owner" button above, and once complete, you can log this cache.
Thanks and happy caching!
QUESTIONS
1. Observe the marble outside the WVU Mountainlair (stage 1). Is there any evidence of minerals in the marble, and if so, which of the four options listed on the cache closely resembles what is seen at ground zero?
2. Look for the faces on the outside of Stewart Hall (stage 2). Do you think sandstone was the best choice for this building?
3. Compare the weathering of the two buildings. Although the Mountainlair has tall, thin marble structures, is it more or less susceptive to the effects of weathering?
(Optional) Locate the benchmark in front of Stewart Hall and lie on the ground next to it to take your picture.
The WVU Mountainlair, located in the heart of West Virginia University's Morgantown campus, serves as a bustling student union with a variety of services, dining options, and entertainment venues. For geocachers, it offers a prime location to start or end a campus-based adventure, as it's surrounded by scenic spots, historical landmarks, and hidden treasures waiting to be discovered. With its central location and proximity to hiking trails, the Mountainlair is an ideal waypoint for those exploring the area’s geocaches, blending both urban and nature-based experiences. This earthcache will have you take a closer look at the marble that makes the facade.
The Geology of Marble
Marble is a metamorphic rock primarily composed of recrystallized carbonate minerals, most commonly calcite or dolomite. It forms when limestone undergoes heat and pressure over millions of years, resulting in its characteristic crystalline structure. The purity of the original limestone determines the color and appearance of marble, which can range from pure white to a variety of colors due to mineral impurities. The black granular coloration in marble is typically due to the presence of dark-colored minerals such as:
1. Graphite: A carbon-based mineral that can appear in black or dark gray veins and patches.
2. Magnetite or Hematite: Iron oxide minerals that may create dark, often granular spots or streaks.
3. Bituminous Materials: Organic substances trapped during the rock's formation, which can give a dark, almost oily appearance.
4. Pyrite or other Sulfides: Occasionally, these can introduce darker hues, especially if they are finely dispersed.
The distribution and density of these impurities can cause black spots, veins, or more homogenous dark tones in the marble, creating distinct patterns that are often highly prized in decorative applications.
Marble is not a common natural resource in West Virginia, but the marble used in the facade of the WVU Mountainlair was likely sourced from outside the state, as West Virginia is more known for its limestone, sandstone, and coal deposits. The marble used in construction projects such as the Mountainlair typically comes from quarries in regions known for high-quality marble, such as Vermont, Georgia, or even Carrara, Italy. These locations are renowned for producing marble with the fine texture and durability needed for architectural purposes. Therefore, the marble at the Mountainlair was likely quarried from one of these well-established marble-producing regions.
Stewart Hall, one of the oldest and most iconic buildings on West Virginia University's Morgantown campus, is a historical gem that stands out for its stunning architecture and rich academic history. As a result of its age, this building has weathered the impacts of Mother Nature over the years (see what I did there). I hope you enjoy taking a closer look at this iconic building on campus.
Sandstone is a sedimentary rock composed mainly of sand-sized mineral particles, typically quartz, feldspar, and other rock fragments. Its formation occurs when sand is buried, compacted, and cemented together over time by natural minerals, often silica, calcite, or iron oxides, creating a durable and relatively porous rock.
Geological Characteristics of Sandstone
- Composition: Sandstone’s primary component, quartz, is highly resistant to weathering, which contributes to the durability of the stone. However, the secondary minerals (feldspar, mica, and others) and the nature of the cement holding the grains together can vary, affecting the stone’s resilience.
- Texture: Sandstone is usually medium-grained and can range from smooth to gritty in texture, depending on the size of the grains. The spaces between these grains make the rock porous, which influences how it interacts with water and air.
- Stratification: Often, sandstone exhibits visible layers, known as bedding or stratification, due to its sedimentary origins. These layers can affect its structural strength when used in construction.
Sandstone in Construction of Old Buildings
Sandstone has been widely used in historical architecture due to its availability, workability, and relative durability. Many old buildings, cathedrals, and monuments in regions where sandstone is abundant have been constructed from this material.
Sandstone is abundant in West Virginia, especially in regions where sedimentary rock formations dominate the landscape. Known for its durability and ease of carving, sandstone has been used in numerous historic buildings throughout the state. The sandstone used in the construction of WVU's Stewart Hall, completed in 1902, was likely quarried locally, possibly from the Hampshire Formation or similar nearby deposits in the Appalachian region. These quarries produced high-quality, buff-colored sandstone, which was favored for its aesthetic appeal and workability, making it an ideal choice for the detailed architectural features seen in Stewart Hall.
Weathering of Sandstone in Old Buildings
The weathering of sandstone is influenced by its mineral composition, porosity, and the environmental conditions it is exposed to over time. Key weathering processes include:
1. Physical Weathering (Mechanical)
- Freeze-Thaw: Water can seep into the pores and cracks of the sandstone, and when temperatures drop, the water freezes and expands, gradually breaking apart the stone. This process is common in climates with fluctuating temperatures.
- Salt Crystallization: In coastal or arid environments, saltwater can penetrate the sandstone and, upon evaporation, salt crystals form and expand within the stone, causing it to disintegrate.
2. Chemical Weathering
- Dissolution: The calcite cement that holds the sand grains together can dissolve when exposed to acidic rain or groundwater, weakening the rock over time.
- Oxidation: Iron oxides in the sandstone may oxidize when exposed to oxygen, leading to rust-like staining and gradual breakdown of the rock's structure.
3. Biological Weathering
- Lichens and Moss: Organisms like lichens and mosses can grow on the surface of sandstone, especially in damp environments. Over time, their roots can penetrate the rock, contributing to physical breakdown.
Impact of Weathering on Historic Structures
The weathering of sandstone in old buildings leads to:
- Surface Erosion: The gradual wearing away of the surface, leading to loss of fine details in carvings or smoothness in walls.
- Cracking and Scaling: Expansion and contraction due to weather conditions can cause cracks and the detachment of stone layers.
- Discoloration: Chemical weathering, especially from pollution, can lead to blackening or staining of the stone's surface.
While sandstone is generally durable, its vulnerability to weathering requires periodic maintenance to preserve historical buildings. Conservation efforts often involve sealing the stone or adding protective coatings to slow down weathering processes.