Why are index fossils important in correlating rock layers?

Certain fossils, called index fossils, help geologists match rock layers. To be useful as an index fossil, a fossil must be widely distributed and represent a type of organism that existed for a brief time period. Index fossils are useful because they tell the relative ages of the rock layers in which they occur. Why

What is the structure of igneous rock?

The structure of an igneous rock is normally taken to comprise the mutual relationships of mineral or mineral-glass aggregates that have contrasting textures, along with layering, fractures, and other larger-scale features that transect or bound such aggregates. What are the structure and texture of igneous rock? The texture of igneous rocks depends on the composition

What is the mineral content of vesicular rhyolite?

The mineralogical composition of rhyolite is defined as containing mostly quartz and feldspar with a total silica content of more than 68%. What minerals are in vesicular rhyolite? Rhyolite is extrusive equivalent of granite magma. It is composed predominantly of quartz, K–feldspar and biotite. It may have any texture from glassy, aphanitic, porphyritic, and by

Which layers of the earth is solid?

The solid, outer layer is called the crust. Below the crust lies a layer of very hot, almost solid rock called the mantle. Beneath the mantle lies the core. The outer core is a liquid mix of iron and nickel, but the inner core is solid metal. What are the 4 layers that are solid?

Which era is the longest?

The longest geologic era was the Precambrian. It began with the formation of the earth about 4.53 billion years ago, and ended about 542 million years… Which era lasted the longest? The Precambrian era lasted the longest. This era lasted from the formation of the earth about 4.5 billion years ago to the start of

Where are Magma cubes in Minecraft?

the Nethernear Nether Fortresses and Basalt Deltas. When they move, they jump and momentarily unravel into eight layers, giving them the appearance of a spring while revealing a yellow core inside. Where can I find a magma cube spawner? There is always a magma cube spawner in each bastion remnant of the treasure room type.

What animals were in the Quaternary Period?

These steppes supported enormous herbivores such as mammoth, mastodon, giant bison and woolly rhinoceros, which were well adapted to the cold. These animals were preyed upon by equally large carnivores such as saber toothed cats, cave bears and dire wolves. What animals first appeared in the Quaternary Period? The Quaternary Period: A Time Of Giant

What are the advantages of strip mining?

On a production basis, comparing fatalities per million tons, strip mines are over four times safer than underground mines; and on an exposure basis, comparing fatalities per million man hours, strip mines are approximately twice as safe. This disparity in numbers is due to the higher productivity of the strip mine.4 дек. 1971 What is

What are ocean currents 7?

Ocean currents are streams of water flowing constantly on the ocean’s surface in definite directions. They are caused by differences in the temperature and salinity of water, by wind, solar heating and gravity. The winds majorly responsible for creating ocean currents are the Westerlies and the Trade winds. What are ocean currents Grade 7? Answer:

When did Kostal Cone last erupt?

1550 (?) Kostal Cone Geology Age of rock Holocene Mountain type Cinder cone Last eruption 1550 (?) When did the last cinder cone volcano erupt? Cinder Cone and the Fantastic Lava Beds Cinder Cone Geology Mountain type Extinct Cinder cone Volcanic arc Cascade Volcanic Arc Last eruption 1666 How often does a cinder cone volcano

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