Geology Commons^™

Earth's Place In Space, John J. Renton, Thomas Repine

Readings and Notes

I've always thought that a story should start at the beginning. Since this book is the story of Earth, we will start at the beginning. According to the astronomers, in the beginning, there was no need for geology because there were no minerals or rocks; there was no Earth; there was no Sun; there were no stars or planets. According to the astronomers, there was a time when even our present universe didn't exist. In the 1920s, the Belgian astronomer Georges Lemaitre hypothesized that everything presently contained within the entire Universe was once compressed into in a sphere he called …

The Pennsylvanian Period, John J. Renton, Thomas Repine

Readings and Notes

In many respects, the mountain building of the Acadian Orogeny never really came to an end. Following the collision of Avalonia with the eastern margin of Laurasia with the subsequent creation of the Acadian Highlands, Gondwana and South America, now joined together into a single continent, were approaching from the east and south respectively. Even before the continent-continent collision that would occur at the close of Permian time, the highlands of Acadia along the eastern margin of Laurasia and Llanoria along the southern margin were being maintained as uplands in response to the compressional forces generated by the converging continents. …

The Ordovician Period, John J. Renton, Thomas Repine

Readings and Notes

The Ordovician Period extends in time from 505 million years ago until 438 million years ago. You will remember from our discussions of the Cambrian that the Ordovician Period of time and the Ordovician System ofrocks was suggested by Professor Lapworth as a means of solving the dilemma presented by Murchison and Sedgewick as to the "ownership" of a section of rock that both claimed when Murchison wanted to include the upper portion of Sedgewick's Cambrian System as the lower portion of his Silurian System. Sedgewick, you will remember, responded by demanding that the lower portion of his Silurina System …

The Jurassic Period, John J. Renton, Thomas Repine

Readings and Notes

During the Jurassic Period, Europe was covered by a shallow sea in which a rich fauna was encapsulated in sequences of limestones and shales. These Jurassic rocks were the training ground for many of the early geologists as they began to formulate some of the basic precepts of geology. Foremost amongst these was William Smith (1769-1839) who was the first to discover how to use fossils to correlate between separated outcrops. He gained his knowledge and understanding of fossils in his profession of a surveyor and in the building of canals throughout southern England where the canals were cut into …

Oceans And Shorelines, John J. Renton, Thomas Repine

Readings and Notes

Until 1872 when H.M.S, Challenger, a British warship converted for research, made its historic voyage, relatively little was known about the oceans. The voyage, funded by the British government, was mandated to chart the depth of the ocean, measure the various ocean currents, amass data on the composition of the ocean's water and bottom sediments, and collect information on ocean life. At the time of the voyage, except for a few soundings, almost nothing was known about the ocean bottom. Most scientists of the day had considered the vast expanses of the deep ocean basins to be nothing more than …

Deserts And Wind, John J. Renton, Thomas Repine

Readings and Notes

About one third of Earth's land surface is either arid (< 10" ppt./yr or semi-arid (10" to 20" pt./yr). While most precipitation is in the form of rain, some may be provided by melting snow, mist, or fog. With limited availability of water, rocks are not subjected to chemical weathering but rather to physical weathering.

Igneous Rocks, John J. Renton, Thomas Repine

Readings and Notes

No abstract provided.

Geologic Time, John J. Renton, Thomas Repine

Readings and Notes

It is not surprising that humans have wondered how long Earth has existed. At one extreme, there were the Brahmans of India who believe that Earth never had a beginning and will never have an end. Others were of the opinion that Earth was old, but perhaps not eternally old. In 450 BC, for example, a Greek historian named Herodotus (484 - 425 BC) expressed the opinion that Earth was very old, basing his estimate on the results of his studies of the Nile Delta. He observed that the delta was growing layer by layer as a result of the …

Earthquakes And Seismology, John J. Renton, Thomas Repine

Readings and Notes

The great majority of earthquakes are caused by the movement of faults. Two terms are used to determine the location of an earthquake, focus and epicenter. The focus of an earthquake is the point along a fault where the rocks slipped and released the energy previously stored during the elastic phase of deformation. Because faults represent brittle deformation, the highest frequency of earthquakes occurs at Earth's surface and decreases with depth as rocks become less brittle and more plastic. The deepest earthquake foci occur at depths of about 640 km. ( 400 mi.) which is the deepest penetration of subducting …

Earthquakes, John J. Renton, Thomas Repine

Readings and Notes

For centuries, earth scientists have known where the major earthquakes occurred. They also knew they occurred in the same locales as the most violent volcanoes, a fact that led to centuries of arguments as to which was the cause of the other. Now we know that they are not cause and effect; they are both associated with the convergent plate margins. During the mid-1900s, another major zone of both volcanic and earthquake activity was discovered, namely the divergent margins, the most important site being the oceanic ridges. Since then, we have also come to understand the occurrence of volcanic activity …

The Triassic Period And The Beginning Of The Mesozoic Era, John J. Renton, Thomas Repine

Readings and Notes

The Triassic Period is the first period of the Mesozoic Era, a span of time from 245 million years ago to 66 million years ago. Although the Mesozoic era commonly known as the "Age of the Dinosaurs,', it should be pointed out that there were other important evolutionary developments taking place such as the appearance of the first mammal birds and flowering plans. The onset of the Mesozoic Era, the Triassic Period, was also a time of profound tectonic activity affecting the entire North American craton. In the east, the primary event was the breakup of Pangea and the formation …

Coal Genesis, John J. Renton, Thomas Repine

Readings and Notes

Most textbooks classify coal as a sedimentary rock even though it does not fit the definition of a sedimentary rock. While a sedimentary rock is a "rock formed from the products of weathering and erosion", coal forms from the remains of land plants. In fact, coal doesn't even fit the definition of a rock. A rock is defined as "mixture of minerals" and minerals are defined as "natural occurring, solid, inorganic substances ..• " Coal is composed largely (􀀴90+%) of organic substances (macerals) which, by definition, are not minerals. If coal must be classified as a rock, because it forms …

Geology, The Marcellus Shale, Experts, And Dispute Resolution, Itzchak E. Kornfeld

West Virginia Law Review

No abstract provided.

A Geological And Geophysical Investigation Of Ice Mountain Algific Talus, Hampshire County, West Virginia, Kevin M. Andrews

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ice Mountain is an algific talus slope located in Hampshire County, West Virginia, protected for its status as a biological refugium. Both the origin of the slope and the mechanism by which cold air is produced from the base of the slope have remained mysteries to local residents and tourists for many years. This research effort takes a scientific approach to exploring the mysteries of Ice Mountain. Bedrock and surficial geologic mapping provides an understanding of the physical environment of the slope area, while geophysical survey data provide clues to the subsurface of the slope. The algific talus consists of …

Revised Glacial Margins And Wisconsin Meltwater Paleoflood Hydrology In Slippery Rock Creek Basin, Central Western Pennsylvania, Gary John D'Urso

Graduate Theses, Dissertations, and Problem Reports (ETD)

Glacial margins mapped in Slippery Rock Creek basin during the 1950s are problematic. The number of sedimentological, mineralogical, petrological, and textural analyses used to distinguish glacial drifts in the southern portion of the basin were inadequate to resolve the margins. Furthermore, misidentification of man-made deposits as glacial drift led to erroneous interpretations regarding the extent and character of pre-Wisconsin glacial deposits, and appears to have influenced subsequent soil mapping. Canadian Shield erratic weathering was the primary tool used in this study to re-investigate the glacial margins. Erratics display one of three distinctive weathering rinds, so glacial deposits can be differentiated …

Geology Of The Southern Half Of The Millerstown, Pennsylvania 15 Minute Topographic Quadrangle, George Calvert Robinson

Graduate Theses, Dissertations, and Problem Reports (ETD)

A detailed investigation of the geology of the southern one-half of the Millerstown, Pennsylvania 15 Minute Topographic Quandrangle was conducted during 1956-1957. This report of the work contains a description of the Silurian, Devonian, and Mississippian formations which crop out in the area. The complex folding and faulting of the sediments is outlined in a section on structural geology. A number of anticlines and synclines, not previously mapped, are described.

A geologic map and two structural cross sections with a scale of 1:24000 are included to illustrate the features described. This is the first geologic map of the area on …

Petrology Of The Upper Marietta And Hundred Sandstones In Southeastern Ohio, Wayne Dudley Martin

Graduate Theses, Dissertations, and Problem Reports (ETD)

A petrographic study was made of two Lower Permian (Dunkard Series) sandstones in southeastern Ohio. The sandstone members with which the investigation was concerned are the Upper Marietta sandstone and the Hundred sandstone. The study was made in order to determine the origin of the sandstones and the practicability of applying geologic methods to the grindstone industry. The results of the study indicate that although some of the constituents of these sandstones were derived from igneous and sedimentary source rocks, a relatively large amount of material was derived from metamorphic rocks. The detritus was transported from the east and deposited …