Paleontology

Pumice is Extrusive after it has been envelop from the volcanoes eruption! it can somehow be a intrusive but very "rare". It is however very light and bumpy felling!

Corals have existed for the greatest length of time according to the fossil record, dating back over 500 million years.

Fossils of an organism that lived relatively recently would be expected to be found in younger layers of rock, as they would not have had sufficient time to become buried and fossilized in older layers. Fossils of older organisms tend to be found in deeper, older layers of rock.

It is surmised that the supercontinent of Pangea formed during the Early Permian Period about 270 million years ago. It began breaking up during the Jurassic Period.

The Devonian period lasted for approximately 60 million years, from about 419 million years ago to 359 million years ago.

Key political issues during the New South era included the post-Civil War reconciliation between North and South, the rise of Jim Crow laws leading to segregation, industrialization and modernization efforts in the South, and the shift in power dynamics within the Democratic Party in the region. These issues reflected the broader social and economic changes that were transforming the South in the late 19th and early 20th centuries.

During the Precambrian Era, bacteria and archaea dominated as the most abundant life forms. These early microorganisms laid the foundation for the development of more complex life forms that emerged later in the geological time scale.

Plants can be divided into two large groups: vascular plants, which have tissues specialized for transporting water and nutrients, and nonvascular plants, which do not have these specialized tissues. Another way to classify plants is into gymnosperms, which produce seeds that are not enclosed in a fruit, and angiosperms, which produce seeds that are enclosed in a fruit.

The longer that magma is able to cool, the larger the crystals will be. Intrusive rocks will have larger crystals than extrusive rocks. For example granite (intrusive) has larger grains than rhyolite (extrusive).

The shortest division in the geologic time scale is an Epoch. Epochs are subdivisions of a period and are typically tens of millions of years long.

The Phanerozoic eon began around 541 million years ago, following the Precambrian eon. It is characterized by the proliferation of diverse complex life forms and is divided into three eras: the Paleozoic, Mesozoic, and Cenozoic.

Volcanic glass is an extrusive igneous rock. It forms when molten lava cools quickly on the Earth's surface, preventing the formation of crystals.

Deck chairs first appeared at the seaside in the early 19th century, around the 1880s. They were initially designed to provide visitors a comfortable and portable seating option while enjoying the beach and ocean views.

If a rock has large crystals, it is an intrusive rock. Intrusive rocks form underneath the Earth's surface. Magma cools slowly so it has time to form large crystals. An example is granite, where you can see the crystals with your naked eye. Rocks that have small crystals are extrusive rocks. Extrusive rocks are ones that form from lava (blasted out of a volcano) so they cool very quickly, not allowing large crystals to form. An example is obsidian, where you cannot visibly see the small crystals; it just looks like one black, glassy rock.

No, cavemen are not 1 billion years old. The first known appearance of hominids, which includes early human ancestors, dates back to around 6 to 7 million years ago, not 1 billion years ago. The term "cavemen" typically refers to prehistoric human ancestors who lived in caves during the Stone Age, which began around 2.6 million years ago and lasted until about 10,000 years ago.

Yes. The only exceptions would be if tectonic forces either overturned the rock layers through folding or if older layers were thrust on top by a thurst fault. A thrust fault would be apparent if you see the same layers repeat.

A rock.

E.g.

Conglomerate-Quartz(sometimes)

Gabbro-Augite, Mica

Limestone-calcite(made up of dead underwater creatures)

Relict features in carbonates are known as allochems and can be lithics or fossils. Minerals are the building blocks of rocks, like elements are the building blocks of minerals, that said rocks can be made up of entirely one element or mineral. Known as native ore deposits you would call something native - e.g. native copper.

The Jurassic period is named after the Jura Mountains in Switzerland where significant geological strata from this time period were first studied. These rocks contain abundant fossils from the Jurassic period, which lasted from approximately 201 to 145 million years ago.

Geologists have divided Earth's history into manageable units called eons, eras, periods, and epochs. These divisions help scientists study and understand the Earth's geological and biological history over millions of years.

1. Cubic: crystals have 6 sides.
2. Tetragonal: crystals have 4 sides.
3. Orthorhombic: crystals have 3 unequal sides.
4. Hexagonal: crystals have 6 sides.
5. Monoclinic: crystals have 4 sides.
6. Triclinic: crystals have no set number of sides.

You can date rock layers by radioactive dating using half-life in the igneous rock layers that contain radioactive isotopes like uranium or potassium. These isotopes decay at a known rate to stable daughter isotopes, allowing scientists to determine the age of the rock based on the ratio of parent to daughter isotopes present. Sedimentary rock layers cannot be dated directly using radioactive dating due to the possibility of contamination and the absence of radioactive isotopes in the rock itself.

From youngest to oldest:

1. Permian

2. Pennsylvanian

3. Mississippian

4. Devonian

5. Silurian

6. Ordovician

7. Cambrian

Scientists can learn about the evolution and distribution of clam species throughout different time periods by studying clam fossils. Fossilized clams can also provide insight into past environments, such as water temperatures and oxygen levels, as well as help determine the age of rocks and sediment layers in which they are found. Additionally, clam fossils can offer information on past biodiversity and ecological interactions.

Radiometric dating is least useful for dating sedimentary rocks because they are formed from the accumulation of sediments, making it difficult to determine the original isotopic composition.

The heavy bombardment period, known as the Late Heavy Bombardment, is estimated to have occurred about 4.1 to 3.8 billion years ago. This period was characterized by intense asteroid and comet impacts on the inner planets of the solar system, including Earth.