Earthquake An earthquake is the shaking or trembling of the earth, which may be natural or man-made (e.g., due to atomic explosion) in origin. An earthquake is a sudden, strong movement or slipping of the earth’s crust that result in a sudden release of energy. Earthquakes occur at certain locations where the tectonic plates which form the earth’s crust, coincide. Populations that live near the...

Estimates of the chemical composition of the bulk (entire) Moon fall into two drastically different categories. One group of estimates claims that the Moon is enriched in refractory elements (those that boil at high temperatures, such as calcium and aluminum) by about 50% compared to Earth. The other group claims that the abundances of refractory elements are the same in the Earth and Moon. Two...

one of the most intensive occurrences of magmatism in iran was in the middle jurassic period. among the granitoid intrusions in this period as discrete bodies or complexes can be pointed to aligoodarz, alvand, astaneh, boroujerd, malayer, and chah-dozdan in the sanandaj-sirjan zone; shir-kuh and ayrakan in the central iran zone; shah-kuh, sorkh-kuh and kalateh-ahani in the lut block. these gran...

The earth dynamic system is one of the key scientific questions on the earth science. The thermodynamic behavior and gravity force of the earth and the rheology nature of the mantle prove that mantle convection is the main power source leading the lithosphere to break and move. Yet the directivity of both the structures in the crust and plate movement reminds of the earth rotation. Here we demo...

This paper looks at the challenges confronting plate tectonics— the ruling paradigm in the earth sciences. The classical model of thin lithospheric plates moving over a global asthenosphere is shown to be implausible. Evidence is presented that appears to contradict continental drift, seafloor spreading, and subduction, as well as the claim that the oceanic crust is relatively young. The proble...

Samarium-neodymium isotopic data on whole rocks and minerals of the Sudbury Complex in Canada gave an igneous crystallization age of 1840 +/- 21 x 10(6) years. The initial epsilon neodymium values for 15 whole rocks are similar to those for average upper continental crust, falling on the crustal trend of neodymium isotopic evolution as defined by shales. The rare earth element concentration pat...

T h e Ear th ' s man t l e , core , a n d crus t com­ prise 9 9 . 9 8 % of its mass . T h e man t l e , m a k i n g u p t he bulk of t he mass at 70% a n d com­ posed of h i g h e r densi ty rocks (rich in m a g n e ­ sium silicates, p lus some i ron silicates), ex­ t ends an average of 1 5 2 9 0 0 km d e e p . T h e core is the cen te r of t he Ea r th , 2 9 0 0 6 3 7 0 km d e e p , c o m p o ...