Answers 2025.
Which lines get closer together as they approach the poles? Lines of latitude of lines of
longitude (circle one)? - Answer Latitude and longitude comprises a grid system of lines
encircling the globe and is used to determine the locations of points on the earth. Lines of
latitude, also called parallels, run east - west. Latitude lines always run parallel to each other,
and hence, they are always an equal distance apart.
What could explain the asymmetry of magnetic stripes on the ocean floor? - Answer The
magnetic stripes represent fluctuating polarity changes of the Earth's magnetic field preserved
in the basaltic ocean crust. The reversals have been dated using K-Ar dating producing a
paleomagnetic time scale
What is the difference between fracture and cleavage for a mineral? How can you distinguish
between them when looking at a sample? - Answer Fracture is the characteristic way a
mineral breaks. The difference between cleavage and fracture is that cleavage is the break of a
crystal face where a new crystal face is formed where the mineral broke, whereas fracture is the
"chipping" of a mineral.
What does mafic mean? What are two mafic minerals? - Answer Mafic is an adjective
describing a silicate mineral or igneous rock that is rich in magnesium and iron, and is thus a
portmanteau of magnesium and ferric. Most mafic minerals are dark in color, and common rock-
forming mafic minerals include olivine, pyroxene, amphibole, and biotite.
What does felsic mean? What are two felsic minerals? - Answer In geology, felsic refers to
igneous rocks that are relatively rich in elements that form feldspar and quartz. ... Felsic refers
to silicate minerals, magma, and rocks which are enriched in the lighter elements such as
silicon, oxygen, aluminium, sodium, and potassium.
What does the Bowen's reaction series represent? - Answer Bowen determined that specific
minerals form at specific temperatures as a magma cools. At the higher temperatures
associated with mafic and intermediate magmas, the general progression can be separated into
two branches.
How do porphyritic-textured igneous rocks form? - Answer Porphyritic rocks are formed when
a column of rising magma is cooled in two stages. In the first stage, the magma is cooled slowly
deep in the crust, creating the large crystal grains, with a diameter of 2mm or more.