It covers plate-tectonic processes including extensional regimes, subduction zone processes, and collisional processes such as the formation of the Himalaya. The module is intended for those with an understanding of the essentials of igneous and metamorphic rock-formation processes, plate-tectonic theory and structural processes.

This fine-grained basalt comes from the Isle of Staffa, which lies east of the Isle of Mull in the Inner Hebrides of Scotland. The island is perhaps most famous for the rock formation known as Fingal’s Cave, which exhibits striking columnar jointing in a basalt lava flow, and inspired part of the Hebrides Overture by the romantic composer ...

A basalt is a fine-grained basic igneous rock containing essential calcic plagioclase feldspar and pyroxene (usually Augite), with or without olivine. Basalts can also contain quartz, hornblende, biotite, hypersthene (an orthopyroxene) and feldspathoids.

Each rock is systematically discussed under the following headings: definition and classification, photomicrographs of the whole rock under the microscope, rock-forming minerals under the microscope (essential and non-essential minerals), and varieties.

Nov 13, 2015 · Basalt is a fine-grained igneous rock that may exhibit hues of dark green, reddish brown, dark gray, or black. Like other igneous rocks, basalt is associated with volcanoes, forming through the solidification of a molten state. Basalts may vary greatly in composition and form.

Petrography standard test of basalt was performed using petrographic microscope, and petrographic thin sections were observed under cross polarized light (CPL) and plane polarized light (PPL),...

Rocks under the microscope: activity instructions. Geologists sometimes use microscopes to identify the rocks they are looking at. This is a skill that geologists use to help them make observations and draw conclusions from the samples they are analysing.

It covers plate-tectonic processes including extensional regimes, subduction zone processes, and collisional processes such as the formation of the Himalaya. The module is intended for those with an understanding of the essentials of igneous and metamorphic rock-formation processes, plate-tectonic theory and structural processes.

This is a 10X magnification picture of a Basalt, a common Volcanic igneous rock. Volcanic rocks form from Lavas which erupt at the surface and cool rapidly. The lava that erupted to make this basalt is of about the same composition as the magma that cooled to make the Diabase, so the crystallizing minerals are similar.

Sample 10072 is a fine-grained vesicular basalt that crystallised 3.6 billion years ago (measured by Ar/Ar, Rb/Sr and Sm/Nd methods). Its texture is best described as sub-ophitic and intersertal. Plagioclase feldspar, pyroxene and ilmenite are the three main constituents.