Blount Springs Observation

The Lynne deposit lies within the early Proterozoic Penokean fold belt of the southern province of the Precambrian Shield. The fold belt is divided into two major terranes in Wisconsin (Sims 1989). The first is the northern Penokean terrane, which contains major oxide facies iron formations and granitic intrusions (DeMatties 1989). The second major terrane, separated from the Penokean terrane by the Niagara fault zone, is the Wisconsin magmatic terrane, characterized by a volcanic island arc-basin assemblage (Sims 1989). This southern terrane lacks major oxide facies iron formations, but contains abundant tonalite-granite intrusions (DeMatties 1989). The Wisconsin magmatic terrane is further subdivided into the northern Pembine-Wausau terrane and the southern Marshfield terrane, which are separated by the Eau Pleine shear zone, a north-dipping subduction zone (Sims 1989).

On the first side of the outcrop the rock when examined was greenish and had small black grains indicative of diorite with hornblende giving the green color. The rock was similar to the outcrop encountered at Hollow rock which also had several fractures parallel although not as many, and that outcrop was also highly weathered. On the other side of the outcrop, the rock was incredibly different. This side was not weathered beyond recognition but

One of the major things noticeable from the cross section is that quite a few of the rock layers are over turned, where the older rock layers are above the newer rock layers. This is seen in the contact between the Quartz Monzonite of Papoose Flat and the Campito Formation which is also a disconformity. Next there is some fault zones separating the Camptio, Poleta, and Harkless formations. We then see some more overturned layers with the contacts between Saline Spring Valley Formation (lower and upper members) above the Mule Spring Formation along with some inferred folding. With a normal fault separating the inferred folding event, we see where the overturning occurs. In between the Cambrian layers we see Tertiary Basalt nonconformities also being folded, thus with that we know that the folding event was more recent than the formation of the Basalt. Next there is a large Basalt field with a spot of the Harkless formation. Again we see over tuning as the Basalt field ends there are the Devonian and Mississippian rock Layers on top of the basalt. Separating these overturned layers from the Harkless Formation and the Saline valley Formation (upper member), which are not overturned, is a thrust fault. From this information, there was a major stress event sometime after the Tertiary period causing the rock layers to fold and overturn. And from this stress event and from the folding, normal and thrust faults are formed. Finally we see that there were alluvial and landslide deposits from the Quaternary after the folding, faulting, and over

Questions and charts are from Geoscience Laboratory, 5th ed. (p. 133-150), by T. Freeman, 2009, New York, NY: John Wiley & Sons. Reprinted with permission.

Determining the location of the Shawangunk Mountain formation from our position on the outcrop can demonstrate a lot about the upbringing of this formation. The Shawangunk Formation, consisting of quartz pebble conglomerate from the Middle Silurian age, extends from south of the Hudson Valley down south until Virginia. The vanishing of the formation within the area of Rosendale, NY has led to investigations of tectonic events. Due to the Taconic orogeny, we see the formation of the Shawangunk Mountains being formatted. Through the transgression of fluvial system, the Shawangunk Mountain formation rose southeast as the result of the tectonic deformation. The coarse-grained beds in the lower portion of the outcrop demonstrate a very

During the Late Kaskaskia (Cratonic Sequence 3), what type of deposition predominated on the craton?

Questions and charts are from Geoscience Laboratory, 5th ed. (p. 155–167), by T. Freeman, 2009, New York, NY: John Wiley & Sons. Reprinted with permission.

The country rock was identified in the field to be a Meta-Limestone, but a more in-depth chemical analysis done by others classifies it as a dolostone of the Strath Suardal formation from the Durness group. (Digimap, 2017) (Goodenough et al. 2011)

Starved rock and St. Peter Sandstone are an erosional remnant of Ordovician period. These remnants contain Pennsylvanian clastics that survived the washing out of the Illinois River at the end of the Ice Age. Evidence for swift, turbulent, and deep water includes gravel bars and erosional features as high as 160 feet above the current level of the river, massive cross bedded sand, and gravel deposits along the river course.

Past 360 million years ago, Kentucky was approximately 10 degree to the south of the equator when caves started to form. Kentucky was also occupied with water containing tiny organism having shells of calcium carbonate. When these tiny organisms died, shells accumulation of these creatures together with calcium carbonate emanating from water, built up more than millions of years such that it was hundreds of feet thick. On top of these formations, fifty feet of sandstone were deposited by another river system. Sandstone and limestone were exposed when the sea level started to fall approximately 280 million ago (Thompson & Thompson, 2003). When rivers that we have today started to form, sandstone topped plateau covered the Green River whereas a low limestone plain extended towards southeast direction (Call,

The quadrangle is considered to be a part of the Allegheny Plateau, so the rocks in this region are mostly of Carboniferous age. Carboniferous rocks are subdivided into two series: the Pennsylvanian and Mississippian. The rocks of both series mainly consist of alternating beds of shale and sandstone, but Mississippian rocks on southern parts of the plateau include thick limestones (Phalen 1). Both series are represented in the Johnstown quadrangle. The Pennsylvanian series, however, covers most of the region, while Mississippian rocks appear only at the surface along deeply eroded anticlines.

Approximately 17 meters thick, Unit A defines the lowest third of the Juniata Formation. Fragments of marine fossils, including bryozoans, brachiopods, and gastropods, are commonly found in the bottom-most portion of this unit of structureless mudstone and quartz arenite. Quartz grains in the sandstone beds of Unit A are typically immature and fine-grained, though the sandstone packages tend to coarsen upwards. Though typically structureless, intermittent bedding of the sandstone and shale packages is observed in this unit, and some areas display

The lithology of the Forest Hill in Wayne County is similar to that described for this formation in the counties in central and western Mississippi. The main difference is the occurrence of fossiliferous lenses (marine fossils) in the otherwise darkgray, silty to arenaceous, micaceous, carbonaceous clay. The term "Forest Hill Sand," which has been used in numerous publications, is a poor indicator of the formation's true litho logy, as Bob Ainsworth77 reported in his mineralogical and grainsize data paper published in 1967. His computed averages for Forest Hill samples collected in the Jackson and Vicksburg areas show 51 percent silt, 32 percent sand, and 17 percent clay. In Wayne County the percent of clay is considerably higher.

Mesa Verde National Park on the Colorado Plateau contains many geological aspects of interest, including its sedimentary rock layers, its canyons, its alcoves utilized by ancient people and how these alcoves were formed. Mesa Verde National Park is located in the southwest corner of Colorado, close to the Four Corners area, on top of a high mesa overlooking the Mancos River (Harris et al. 2004). The park, covering 81 square miles, consists of several main sedimentary formations that are characteristic to the park (Encyclopedia Britannica 2015). Canyons are carved into the sedimentary rock, with the cave dwellings found high on their steep walls. These dwellings are an especially unique aspect to the Mesa Verde National Park, and are built out of large alcoves. The alcoves were produced by weathering and erosion of the sedimentary rock type. To better understand how these alcoves formed, we must understand the geology of Mesa Verde National Park and how it has developed over history.

The Piedmont is located between the Coastal Plain and the Mountain regions, in the middle region of the state. The origins of Piedmont are French, meaning “foot of the mountain”, because it’s located at the base of the Appalachians Mountains. From the western Coastal Plane to the mountains, the elevations range from about 300 feet to near 1,500 feet (Seaman 2006). The fall line, or fault zone, lies between the Coastal Plain and the Piedmont. The rivers that flow along the fault line are formed from shoals, low waterfalls and rapids. As the rivers flow from the Piedmont to the coastal Plain the rocks become younger and softer. The streams below the fall line are usually lethargic and smooth-flowing. The streams above the fall line are gravelly and shallow, making boating difficult. As for the land, the Piedmont is called a plateau because it is high and mostly flat. Most geologist separate the Piedmont into two different areas because the rock suites are so different. The eastern part, known as the Carolina Slate Belt and then the western part, known as the Inner piedmont. My main area of focus will be the Carolina Slate Belt, with attention to the ancient