Notes, summaries, assignments, exams, and problems for Geology

Diagenesis: Transforming Sediments into Rocks

Diagenesis encompasses the transformation of sediments into sedimentary rocks. It occurs within the Earth's crust and involves physical and chemical changes. There are three main phases:

1. Early Diagenesis (Syndiagenesis)

This phase occurs in the same sedimentary environment where sediment accumulates. It's characterized by intense biological activity, where detritivorous bacteria and organisms consume organic matter, using CO2 and producing oxygen. Key parameters change with increasing depth:

• Oxygen decreases.
• Dissolved CO2 increases.
• Pressure increases.
• Conditions become increasingly reductive and acidic.

2. Deep Diagenesis (Anadiagenesis)

This phase occurs when sediments are buried hundreds or thousands... Continue reading "Diagenesis and Fossilization in Sedimentary Rocks" »

Precipitation

All forms of water that fall to Earth, including rain, snow, hail, sleet, fog, mist, drizzle, and the measured amounts of each.

Rain Shadow

A dry region on the leeward side of a mountain range resulting from a reduction in rainfall.

Runoff

The draining away of water.

Soil

Soil is the medium for plant growth, the principal factor controlling the fate of water in terrestrial environments, nature's recycling system (which breaks down the waste products of plants and animals and transforms them into their basic elements), and a habitat to a diversity of animal life, from small mammals to countless forms of microbial life.

Short-Day Plant

A plant that flowers only after being exposed to light periods shorter than a certain length, typically... Continue reading "Understanding Key Environmental and Soil Science Terms" »

The News: is the account of an event that has recently occurred and is considered to be of public interest.

Headline: is the heading

Lead: captures the essence of the news, the event that occurred, the location, and the time.

Body: develops the subject matter of the news.

Newspaper: is a publication that collects the most recent news on different topics.

Hyperonyms: words whose meaning includes that of others

Hyponyms: words whose meaning is included in that of others

News Era: where the topic it deals with is briefly indicated.

Gigantism: a disease whose body parts are larger than normal.

Oleaginous: oil substance.

Pronouns: are words that are equivalent to a noun or a nominal group.

Demonstrative Pronouns: are words that refer to an object.

Numeral and

Estuaries are where rivers or streams meet the ocean, often bordered by salt marshes or intertidal mudflats. Out of the 32 largest cities in the world, 22 are located on estuaries. These unique habitats are crucial for nesting and breeding of various animals. Additionally, most of the fish and shellfish consumed by humans have spent part of their lives in estuaries. Estuaries also play a vital role in filtering out sediments and pollutants.

However, estuaries are facing numerous threats due to coastal development, introduction of invasive species, overfishing, dams, and global climate change. These factors have made estuaries one of the most threatened ecosystems on earth.

Types of Estuaries

• Salt Wedge: Formed by rivers like the Mississippi, Columbia,

Flood Irrigation - Least Efficient Irrigation Method

Properties of Matter

Well Cementing: Primary and Remedial Operations

Primary Cementing

Primary cementing is the process of placing a cement sheath in the annulus between the casing and the formation. Its objectives include:

• Removing drilling fluid from the casing interior and borehole
• Placing a cement slurry in the annulus
• Filling the casing interior with a displacement fluid (e.g., drilling fluid, brine, water)

A bottom plug separates the cement slurry from the drilling fluid, while a top plug separates it from the displacement fluid. The bottom plug ruptures upon landing at the casing string's bottom, allowing the cement slurry to flow into the annulus.

Remedial Cementing

Remedial cementing occurs after primary cementing to inject cements into strategic well locations... Continue reading "Well Cementing: Primary and Remedial Operations for Well Integrity" »

The Ideal Soil for Farming: Loam

The best type of soil for farming is loam. Its balanced composition of sand and clay particles creates both large and small pore spaces. This structure provides an ideal environment for plant growth by:

• Ensuring a steady supply of air and water.
• Retaining moisture while allowing excess water to drain, preventing waterlogging.

Loamy soils are also rich in nutrients due to their clay content and are relatively easy to work with. Their pH level typically falls between 5.5 and 8.0, making them suitable for a wide range of crops.

Sandy Soils: The Hungry Type

In contrast to loam, sandy soils are often described as “hungry” because their large particle size and loose structure lead to:

• Rapid drainage, resulting in nutrient

The Seismic Method

An indirect method of study that looks at the variations in the propagation speed of seismic waves as they travel through different materials inside the geosphere.

What are Seismic Waves?

Vibrations generated inside the Earth at the point where an earthquake takes place. They propagate in all directions, and the more rigid the material they pass through, the more quickly they travel. There are three types:

• P waves: Cause the material to vibrate, alternating between compression and dilation. These waves propagate through solids and liquids.
• S waves: Cause the material to oscillate perpendicular to the direction of propagation. They are slower and cannot travel through liquids.
• Surface waves: Generated when P and S waves reach the

Key Concepts in Geology

(exam3)1:superposition=the oldest on the bottom, youngest on top/2:original horizontality=sedimentary layers/lava flows are deposited as flat layers/3:lateral continuity=rocks extend in all directions until they reach the edge of a basin or pinch out/4:cross-cutting=faults and fractures are younger than the rocks they cut through/5:unconformities=missing time/6:inclusions=chunks of weathered rock are older than the rock they are contained in/7:continental drift=Alfred Wegener/8:Alfred Wegener=Pangaea/9:not a major tectonic plate/Juan de Fuca Plate/10: lithosphere=composed of crust and upper mantle/11:continental crust=composed of granite and basalt/12:transform boundary=one colliding plate will be forced because of difference... Continue reading "Understanding Geology: Key Concepts and Terms" »