1st term exam 150 points

1st term exam 150 points

• 1st term exam 150 points

• Midterm 150 points

• 3rd term 150 points

• Final exam 400 points

• Presentation 150 points

• Total 1000 points

• Extra credit – to be announced in the class - may be emailed

Geology and Other Sciences

Earth Science: The science of Geology Earth System Science

• Geology is the science that pursues an understanding of planet Earth

• Physical Geology - examines the materials composing Earth and seeks to understand the Internal Processes that operate beneath, and External Processes upon its surface.
• Historical Geology - seeks an understanding of the origin of Earth and its development through time

What Do Geologists Do?

• Seek to understand all processes that operate on and inside the Earth and on the Hawaiian Islands

• Study:

• Our planet’s long history and origin of Hawaiian islands and their place on the earth in the ocean
• Landforms: volcanoes, reefs, water bodies (ocean, rivers and groundwater), mountains, valleys, glaciers, dunes
• Hazardous processes such as earthquakes, volcanic eruptions, tsunamis, floods, and landslides
• Rocks, minerals, water, geothermal resources of the Hawaiian Islands

Geology Involves Study of:

• Earth Materials (rocks, minerals, soils)

• formation, effects on health, as resource or waste

• Natural Hazards

• Volcanoes and volcanic eruptions, earthquakes, tsunamis, floods, landslides, rockfalls
• minimize loss of life

• Natural Resources – Volcanoes, Reefs, Beaches, Geothermal energy

• Hydrologic Processes of surface/ground water

• Water resources, pollution

• Geologic Process

• Atmospheric, hydrologic, and lithospheric

Earth formed as a planet in the Sun’s Solar system from a nebula: 4,600,000,000 years ago, 4.6 billion years, 4,600 million years

• Earth formed as a planet in the Sun’s Solar system from a nebula: 4,600,000,000 years ago, 4.6 billion years, 4,600 million years

• Life on Earth began: 3,800,000,000 years

• Geology: Science of processes related to:

• Composition, structure, history and life of Earth
• Processes on the earth, landforms and islands

• Geology of Hawaiian Islands:

• Studies entire spectrum of Hawaiian Islands physical environment, Birth and Life of the Isles

• It is geology applied to:

• Islands origin, volcanic formation and life stages
• Awareness of unique geologic environment
• Understand the geologic processes on the islands

Origin and evolution of Earth

• Origin of planet Earth 4,600,000,000 years before present

• Nebular hypothesis – Sun and Solar System
• While this theory incorporates more basic physics, there are several unsolved problems. For example, a majority of the angular momentum in the Solar System is held by the outer planets. For comparison, 99% of the Solar System's mass is in the Sun, but 99% of its angular momentum is in the planets. Another flaw is the mechanism from which the disk turns into individual planets

• Layered structure developed by chemical segregation early in the formation of Earth

Earth is Unique

• No other planet in the solar system currently has the right chemical and physical mix needed to support life

• No conclusive evidence of life existing elsewhere in the universe has yet been discovered as far as we know

A view of Earth Planetary System

• Earth is a planet that is rocky and self-contained – Earth System and Spheres

• Earth’s spheres

• Hydrosphere – water, oceans, lakes, rivers
• Atmosphere - air
• Biosphere – life and environment, ecosystem
• Lithosphere - Solid Earth
• Pedosphere – soil
• Cryosphere – ice sheets, Antarctica, Greenland
• Anthrosphere – Human built environment

Our Planet’s “Five Spheres” or Subsystems

• The Atmosphere:

• Nitrogen, oxygen, argon, carbon dioxide, and water vapor

• The Hydrosphere:

• Oceans, lakes, streams, underground water, snow, and ice

• The Biosphere: Ecosphere, Sphere of Life

• All of Earth’s organisms, as well as any organic matter not yet decomposed, Anthrosphere is Human Living Environment

• The Geosphere – Crust, Lithosphere, Mantle and Core

• The solid Earth from core to surface crust-
• Crust composed principally of rock, minerals, sediments, ores and soils
• Soils are in Pedosphere

The science of Geology

• Some historical notes about geology

• The nature of Earth has been a focus of study for centuries
• Catastrophism
• Uniformitarianism and the birth of modern geology

Uniformitarianism

• Continuity of Cause and Effect

• Apply Cause and Effect to Future - Prediction

• Apply Cause and Effect to Present - Technology

• Apply Cause and Effect to Past - Uniformitarianism

Uniformitarianism does not mean:

• Catastrophes never occur

• Physical Conditions on Earth never Change

• Earth has always been the same

• Physical processes always occur at the same rate or intensity

• Laws of Physics have always been the same

Uniformitarianism does mean:

• Using our knowledge of physical laws, we can test:

• Whether catastrophes have occurred

• Whether physical conditions on earth have changed, and if so, how (climate change, ice ages, warm periods, high or low sea level, etc.)

• Whether physical laws themselves have changed in time, or elsewhere in the universe.

Geologic time

• Geologists are now able to assign fairly accurate dates to events in Earth history

• Relative dating and the geologic time scale

• Relative dating means that dates are placed in their proper sequence or order without knowing their age in years

Geologic time

• The magnitude of geologic time

• Involves vast times – millions or billions of years
• An appreciation for the magnitude of geologic time is important because many processes are very gradual

The nature of scientific inquiry

• Science assumes the natural world is consistent and predictable

• Goal of science is to discover patterns in nature and use the knowledge to make predictions

• Scientists collect “facts” through observation and measurements

The nature of scientific inquiry

• How or why things happen are explained using a

• Hypothesis – a tentative (or untested) explanation
• Theory – a well-tested and widely accepted view that the scientific community agrees best explains certain observable facts

The nature of scientific inquiry

• Scientific methods

• Scientific method involves gathering facts through observations and formulation of hypotheses and theories

• There is no fixed path that scientists follow that leads to scientific knowledge

Earth as a system

• Earth is a dynamic planet with many interacting parts or spheres

• Parts of the Earth system are linked

• Characterized by processes that

• Vary on spatial scales from fractions of millimeter to thousands of kilometers
• Have time scales that range from milliseconds to billions of years

Earth as a system

• The Earth system is powered by the Sun that drives external processes in the

• Atmosphere
• Hydrosphere
• At Earth’s surface

Earth as a system

• The Earth system is also powered by the Earth’s interior, Internal Processes.

• Heat remaining from the formation and heat that is continuously generated by radioactive decay powers the internal processes that produce volcanoes, earthquakes, and mountains

The rock cycle: part of the Earth system

• The loop that involves the processes by which one rock changes to another

• Illustrates the various processes and paths as earth materials change both on the surface and inside the Earth

The face of Earth

• Earth’s surface has two principal divisions

• Continents
• Ocean basins

• Significant difference between the continents and ocean basins is their relative levels

The face of Earth

• Continents

• Most prominent features are linear mountain belts
• Shields

• Ocean basins

• Ocean ridge system – the most prominent topographic feature on Earth
• Deep-ocean trenches

Early evolution of Earth

• Origin of planet Earth

• Most researchers believe that Earth and the other planets formed at essentially the same time from the same primordial material as the Sun
• Nebular hypothesis

• Layered structure developed by chemical segregation early in the formation of Earth

Earth’s internal structure

• Earth’s internal layers can be defined by

• Chemical composition
• Physical properties

• Layers defined by composition

• Lithosphere, Crust
• Mantle
• Core

Dynamic Earth – Plate Tectonics

• Theory of Plate Tectonics

• Involves understanding the workings of our dynamic planet
• Began in the early part of the twentieth century with a proposal called continental drift – the idea that continents moved about the face of the planet
• Seafloor Spreading

Dynamic Earth

• The theory of plate tectonics

• Theory, called plate tectonics, has now emerged that provides geologists with the first comprehensive model of Earth’s internal workings

• Plate boundaries

• All major interactions among individual plates occurs along their boundaries

Dynamic Earth

• Plate boundaries

• Divergent boundary – two plates move apart, resulting in upwelling of material from the mantle to create new seafloor
• Convergent boundary – two plates move together with subduction of oceanic plates or collision of two continental plates

Dynamic Earth

• Plate boundaries

• Transform boundaries - located where plates grind past each other without either generating new lithosphere or consuming old lithosphere
• Changing boundaries - new plate boundaries are created in response to changes in the forces acting on the lithosphere