Geology of Ireland Geology of Ireland The geology of Ireland consists of the study of the rock formations in Ireland. The island contains rocks from every age from Proterozoic to Holocene and a large variety of different rock types is represented. The basalt columns of the Giant's Causeway together with geologically significant sections of the adjacent coast have been declared a World Heritage Site. The geological detail follows the major events in Ireland's past based on the geological timescale. The oldest known Irish rock is about 1.7 billion years old and is found on Inishtrahull Island off the north coast of Ulster. Outcrops
S-type star S-type stars are intermediate between carbon stars and normal giants. They can be grouped into two classes: "intrinsic" S stars, which owe their spectra to convection of fusion products and s-process elements to the surface; and "extrinsic" S stars, which are formed through mass transfer in a binary system. The intrinsic S-type stars are on the most luminous portion of the asymptotic giant branch, a stage of their lives lasting less than a million years. Many are long period variable stars. The extrinsic S stars are less luminous and longer-lived, often smaller-amplitude semiregular or irregular variables. S stars are relatively