Introduction to Geology (PDF)

LEARNING OBJECTIVES At the end of the lecture, the student should be able to: GEOL 11 PRINCIPLES OF GEOLOGY 2ND Sem, AY 2023 – 202...

LEARNING OBJECTIVES At the end of the lecture, the student should be able to: GEOL 11 PRINCIPLES OF GEOLOGY 2ND Sem, AY 2023 – 2024  Define Geology in simple terms; Distribution of these lecture materials  Recognize the different branches of Introduction tocopy), in Explain Geology; and (electronic or hard part or inthewhole, and compare early schools of is strictly prohibited without Geology the thought in Geology. permission from the faculty of NIGS, UP Diliman. Any unauthorized use of these materials shall be subject to disciplinary action (1st Semester, AY 2024-2025). 1  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Introduction to Geology 2  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 LEARNING OBJECTIVES At the end of the lecture, the student should be able to:  Define Geology in simple terms;  Recognize the different branches of Geology; and  Explain and compare the early schools of thought in Geology. 3  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Definition of Geology γῆ + -λoγία gē + -logia geo + logos Earth + study of/ discourse Geology – the study of the earth (and other extraterrestrial bodies), its form and composition, and the processes it has undergone and is undergoing. (Lutgens & Tarbuck, 2012) Geology comes from the Greek word Geo (earth) and logos (study). In short, Geology is the study of the earth. 4  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Definition of Geology Geology is a relatively new field of science. While the study of the earth has been going on for centuries (which we will tackle in the following slides), much of the governing principles of geology was not formulated until the mid-20th century when the Theory of Plate Tectonics was established. Even then, we still have no proof if this theory really holds as we have yet to have the technology to image the interior of the earth. 5  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Geology as a Discipline 1. Relevance of Time o “Geologic” time, Deep Time o All processes/events are relative to each other against time http://science8sc.weebly.com/geologic-time-scale.html Take note that the age of the earth is 4.6 billion years. A large portion of geologic time is lost and we only get to have a more detailed description of each time period during the Paleozoic era when life began to appear on Earth’s record. 6  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Geology as a Discipline 2. Issue of Scale o Small vs Large scale © NAMRIA Geology also deals with the issue of scale. As a practice, geologists are taught to always put a scale on any diagram or picture, since it is common for Geology to deal with both small scale and large scale phenomena. There are consequences to these differences in scale, such as the impact of a certain hazard, so it is always important to ask whether the scale is small or large. 7  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Geology as a Discipline 2. Issue of Scale o Small vs Large scale o Micro vs Macro scale © RMGLumongsod Geology does not only deal with big or macro scale processes that form Earth’s landforms, but also in micro scale features and phenomena that are usually observed under a petrographic microscope. Structures like folds, for example, which you will learn later on in the semester, can occur in both micro and macro scales. 8  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Geology as a Discipline 3. Issue of Scale o Small vs Large scale o Micro vs Macro scale o Local vs Regional scale Geologic phenomena may also be local or regional, and some studies deal with more localized areas (for example, a mountain), while others opt to study the bigger picture (i.e., mountain ranges or continental collisions). Both of which are necessary in understanding the Earth. 9  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Geology as a Discipline 3. Complexity of replicating natural phenomena (Tapponnier et al., 1982) Lastly, since the Earth is very dynamic, Geology deals with complex natural phenomena. To try to go around this, geologists try modelling large scale phenomena using accessible objects and controlled analogs. An example is the Indenter Tectonics model of Tapponier and others as seen in these figures (http://www.ipgp.fr/~lacassin/Extrusion/Extrusion.html), wherein they explain the current regional tectonics and relative position of India, mainland Eurasia, and neighboring plates, using an indenting block analog. While analogs can often encounter minor problems or inaccuracies due to the complexity of natural phenomena, it is still very useful in simplifying otherwise hard to understand concepts. 10  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Work of a Geologist Hindi nawawala ang beer sa mga fieldwork :> 11  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Work of a Geologist Geologists are well-represented in Hollywood movies such as the ones shown here in this slide. In one activity in the future, you will be watching a movie related to Geology and you will be tasked to write a paper explaining if some concepts in the movie were real or not based on what we will be discussing here in the class. 12  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Work of a Geologist A geologist collects samples, measure the attitude of the bed, and make use of surveying tools to collect field data. These data are used to interpret the geologic history of the area and understand the tectonic processes that shaped it. Of course, a well-earned beer awaits them in the conclusion of the fieldwork :> 13  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology 1. Physical Geology o examines the earth’s rocks and minerals and seeks to understand the processes that operate beneath or on its surface o most branches fall under this category 2. Historical Geology o the study of the origin and evolution of the Earth through time There are two primary braches of geology: Physical and Historical. The first 11 chapters of Geol 11 deal with Physical Geology while the last chapter deals with Historical Geology. Each primary branch has their own sub-branches while we will discuss in the next slides. 14  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Physical Geology  Mineralogy  Petrology  Volcanology  Structural geology  Seismology  Environmental geology  Engineering geology  Mining geology  Petroleum geology  Geomorphology  Planetary geology © Alex Strekeisen Mineralogy – study of minerals Minerals – building blocks of rocks Mineralogy deals with both the macroscopic and microscopic scale 15  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Physical Geology  Mineralogy  Petrology  Volcanology  Structural geology  Seismology  Environmental geology  Engineering geology  Mining geology  Petroleum geology  Geomorphology © APACastro  Planetary geology Petrology – study of rocks; Petrography – study of rocks in a microscopic scale 16  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Physical Geology  Mineralogy  Petrology  Volcanology  Structural geology  Seismology  Environmental geology  Engineering geology  Mining geology  Petroleum geology  Geomorphology © APACastro  Planetary geology Volcanology – study of volcanoes 17  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Physical Geology  Mineralogy  Petrology  Volcanology  Structural geology  Seismology  Environmental geology  Engineering geology  Mining geology  Petroleum geology  Geomorphology © JAPEscudero  Planetary geology Structural Geology – deals with structures such as folds and faults; goes hand-in-hand with seismology in studying earthquakes 18  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Physical Geology  Mineralogy  Petrology  Volcanology  Structural geology  Seismology  Environmental geology  Engineering geology  Mining geology  Petroleum geology © iris.edu  Geomorphology  Planetary geology Seismology is the study of earthquakes and the movement of seismic waves through the Earth. This also includes the study of the sources and effects of earthquakes. Through seismology, geoscientists were able to verify that the Earth had different layers. 19  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Physical Geology  Mineralogy  Petrology  Volcanology  Structural geology  Seismology  Environmental geology  Engineering geology  Mining geology  Petroleum geology  Geomorphology  Planetary geology Environmental geology tackles the application of geologic concepts and principles to solve environmental issues. This also includes the effects of humans to the geologic environment and vice versa. 20  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Physical Geology  Mineralogy  Petrology  Volcanology  Structural geology  Seismology  Environmental geology  Engineering geology  Mining geology  Petroleum geology  Geomorphology  Planetary geology © enggeo.co.nz Similarly, engineering geology is the application of geologic concepts for engineering projects. This includes factoring in of geologic hazards and issues in construction and operation. 21  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Physical Geology  Mineralogy  Petrology  Volcanology  Structural geology  Seismology  Environmental geology  Engineering geology  Mining geology  Petroleum geology © RMGLumongsod  Geomorphology  Planetary geology Mining geology is the study of mining resources, particularly through geologic concepts. 22  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Physical Geology  Mineralogy  Petrology  Volcanology  Structural geology  Seismology  Environmental geology  Engineering geology  Mining geology  Petroleum geology © spectro.com  Geomorphology  Planetary geology Like mining geology, petroleum geology is also a field which applies geologic concepts to resource extraction, specifically for petroleum and related products. 23  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Physical Geology  Mineralogy  Petrology  Volcanology  Structural geology  Seismology  Environmental geology  Engineering geology  Mining geology  Petroleum geology  Geomorphology © RMGLumongsod  Planetary geology Geomorphology, as the name implies, deals with the shape of the Earth (landforms) and how these landforms/features were formed. 24  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Physical Geology  Mineralogy  Petrology  Volcanology  Structural geology  Seismology  Environmental geology  Engineering geology  Mining geology  Petroleum geology  Geomorphology © geology.com  Planetary geology Geologic concepts can also be applied to other earth-like bodies, and this is where planetary geology comes in. This photograph was taken by NASA's Mars Rover Curiosity in 2012 using its mast camera. It shows a portion of an outcrop of a rock similar to the conglomerates found on Earth. The pebbles below the rock are clasts that have been weathered from the rock. The photo on the right is a conglomerate outcrop from Earth to show similarity. 25  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Historical Geology  Paleontology  Stratigraphy  Geochronology © 123rf.com Paleontology – study of fossils We study fossils to understand earth’s past In this picture are trilobites, one of the index fossils of the Paleozoic era 26  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Historical Geology  Paleontology  Stratigraphy  Geochronology © McKnight (GeoCorps), 2012 Stratigraphy, on the other hand, focuses on the different layers of rock (formations) that can be found on Earth’s lithosphere and their succession to understand its history more. The photo on the left is an example of the different rock layers that tell the history of an area. Basically, it is like a slice of the Earth’s crust, if the Earth was cake. :) 27  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Branches of Geology: Historical Geology  Paleontology  Stratigraphy  Geochronology ©cameca.com Lastly, geochronology differs from the other branches since it puts everything in the context of time. Time or dating in this case can be relative, as is shown on the chronostratigraphic chart on the right, or absolute, like on the use of Zircon for numerical dating on the left. 28  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Timeline of the Development of Geology  372 – 287 BCE: Theophratus  Peri Lithon, On Stones  Interpretation of fossils  1031 – 1095: Shen Kua  Land formation, erosion of the mountains, and by deposition of silt  1494 - 1555: Georg Agricola  De re metallica libri XII, 1556  First systematic treatise about mining and smelting works Geology as a field of science is relatively new compared to other branches such as physics, biology, and chemistry. Plate tectonics, the governing principle of Geology, was only popularized during the 1960s when the concept of seafloor spreading was observed due to the advancements of technology. That being said, people has been studying earth even during ancient times. Early studies deal with mining, fossils and formation of land. 29  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Timeline of the Development of Geology  1638 - 1686: Nicolaus Steno  Steno’s Laws of Stratigraphy  1700s: Jean-Etienne Guetard & Nicolas Demerest  Geological maps  Volcanic origins of parts of France Nicolaus Steno, a catholic bishop, formulated the Laws of Stratigraphy, the governing principle of Stratigraphy. There are 4 laws: Law of Original Horizontality, Law of Lateral Continuity, Law of Superposition, and Law of Cross-cutting Relationships. These laws will be discussed further in Chapter 12 (Historical Geology). 30  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Timeline of the Development of Geology  1769 – 1839: William Smith  Principle of Faunal Succession  First Geologic Map of Britain  Father of English Geology ©Natural History Museum William Smith observed that each strata contains set of fossils and these arrangement of strata and succession of fossil groups could be found in many parts of England. From here, he formulated the Principle of Faunal Succession 31  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Timeline of the Development of Geology  1785: James Hutton  Father of Modern Geology  Theory of the Earth  1811: Georges Cuvier and Alexandre Brongniart  Stratigraphic succession  1830: Charles Lyell  Principles of Geology © utc.usf.edu  Uniformitarianism Principle concepts of Modern Geology were proposed during the late 18th century and the 19th century, including the principle of Uniformitarianism. 32  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Timeline of the Development of Geology  1912: Alfred Wegener  Continental Drift Theory  1960s: Harry Hess  Seafloor Spreading  1960s: Theory of Plate Tectonics Wegener was the first to propose that continents where once joined together and only drifted to its current positions a million years ago. Although it was disproved, the advancements of technology helped scientists propose the theory of plate tectonics, the governing principle of geology. 33  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Early School of Thoughts Neptunism  Abraham Werner  Rocks have settled out of a large ocean whose level gradually dropped over time © DA Walton (1957) There are two school of thoughts regarding the origin of rocks. First is Neptunism. This theory got its name from Neptune, the Roman god of the sea. 34  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Early School of Thoughts Plutonism  James Hutton  Rocks were formed by emplacement and solidification of lava from volcanoes © ABC News Second is Plutonism. This theory got its name from Pluto, the Roman god of the underworld. During the 18th and 19th century, neptunists and plutonists debated on the origin of rocks. With the recent findings on the origin of rocks, however, we now know that both principles could be applicable in different rocks. For example, the concept of Neptunism is quite similar to the formation of precipitate rocks such as Rock Salt and Gypsum which formed when water saturated with salt and sulfates evaporated, leaving behind precipitates. On the other hand, the formation of plutonic igneous rocks (intrusive igneous rocks) can be explained by the principle of Plutonism. 35  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Early School of Thoughts Catastrophism  Baron Georges Cuvier  16th century  sudden, worldwide catastrophes are the agents of change that alter the physical features of the Earth over time and that the latter remains unchanged in between these periods of upheavals  widely accepted by theologians in the early © Smithsonian Magazine 1800s due to similarity with Biblical events One of the early ideas of Earth and its formation is Catastrophism. It was proposed by Baron Georges Cuvier in the 16th century. It is basically the idea that sudden, worldwide catastrophes are the agents of change that alter the physical features of the Earth over time and that the latter remains unchanged in between these periods of upheavals. Catastrophism was widely accepted by theologians in the early 1800s since it is very similar with Biblical events. Catastrophes are very common in other cultures and religions as well, and they are actually comparable to historical geologic events (https://www.smithsonianmag.com/science-nature/ten-ancient-stories-and- geological-events-may-have-inspired-them-180950347/) 36  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Early School of Thoughts Uniformitarianism  James Hutton  18th century  the Earth is continuously modified by geologic processes that have always operated throughout time (at different rates)  The physical, chemical, and biological laws that operate today also operated in the © utc.usf.edu past. In the 18th century, James Hutton proposed a contrasting idea: Uniformitarianism, which says that the Earth is continuously modified by geologic processes that have always operated throughout time (at different rates). This basically follow the idea that the physical, chemical, and biological laws that govern the processes that we see today must have also been the same for past processes, which eventually shaped the present Earth. 37  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Early School of Thoughts Actualism Uniformitarianism  “The present is the key to the past”  Coined by William Whewell, Popularized by Charles Lyell  Principles of Geology  The earth has been around for a very long time  Things that took a long time: Continental drift, Formation of the Himalayas, Baguio © wiki.sjs.org uplift, Formation of the Philippines Maging crush ako ng crush ko Accepting this concept means admitting that the Earth has been around for a very long time, as opposed to biblical belief that the Earth is still young. Examples of things that took a long time include continental drift, India’s collision with Eurasia, Baguio’s uplift to its present configuration, and the formation of the Philippine Archipelago. While both Catastrophism and Uniformitarianism has their merits, Uniformitarianism is most adopted today due to its more rational, cyclical ideology. Charles Lyell rebranded this idea as “actualism”, and it was generally accepted later on due to his convincing arguments in his book. (https://www.encyclopedia.com/earth-and- environment/ecology-and-environmentalism/environmental- studies/actualism) 38  GEOL 11 PRINCIPLES OF GEOLOGY 1ST Sem, AY 2024-2025 Early School of Thoughts Actualism  “The present is the key to the past”  Coined by William Whewell, Popularized by Charles Lyell  Principles of Geology  The earth has been around for a very long time  Things that took a long time: Continental drift, Formation of the Himalayas, Baguio © wiki.sjs.org uplift, Formation of the Philippines Charles Lyell rebranded this idea as “actualism”, and it was generally accepted later on due to his convincing arguments in his book. (https://www.encyclopedia.com/earth-and- environment/ecology-and-environmentalism/environmental- studies/actualism) 39  At the end of the lecture, we learned that: Geology is the study of the Earth, its form and composition, and the processes it has undergone and is undergoing. GEOL 11 PRINCIPLES OF GEOLOGY In studying Geology, it is important to take 1ST Sem, AY 2024 – 2025 into account the following: relevance of time, issue of scale, and the complexity of replicating natural phenomena. Introduction to Geology has two main branches: physical geology, which examines the Earth’s materials Geology and the various processes that occur beneath or on its surface, and historical geology, which studies the origin and evolution of the Earth through time. The two early schools of thought that shaped Geology as a discipline are Catastrophism and Uniformitarianism. Catastrophism is the notion that Earth processes are sudden and drastic, while Uniformitarianism is the notion that Earth processes are gradual and repetitive or cyclical. 40