The crust occupies less than 1% of Earth's volume. The oceanic crust of the sheet is different from its continental crust.
The oceanic crust is 5 km (3 mi) to 10 km (6 mi) thick and is composed primarily of basalt, diabase, and gabbro.
A theoretical protoplanet named "Theia" is thought to have collided with the forming Earth, and part of the material ejected into space by the collision accreted to form the Moon.
As the Moon formed, the outer part of it is thought to have been molten, a “lunar magma ocean.” Plagioclase feldspar crystallized in large amounts from this magma ocean and floated toward the surface. The upper part of the crust probably averages about 88% plagioclase (near the lower limit of 90% defined for anorthosite): the lower part of the crust may contain a higher percentage of ferromagnesian minerals such as the pyroxenes and olivine, but even that lower part probably averages about 78% plagioclase. The underlying mantle is denser and olivine-rich.
FOREWORD The pursuit of economic development by humanity over the centuries has led to a devastating impact on our environment and all living things. AGRICULTURE CROP AND ITS CLASSIFICATION 214 CROPPING SYSTEM AND PATTERN 218 FARMING SYSTEM SUSTAINABLE AGRICULTUR E 220 221 INTEGRATED FARMING SYSTEM 222 SOIL SCIENCE 225 PARTY 22.•••••••••••••••••• 1f4.
Since the last two decades the international community has been witnessing various challenges. this book "ENVIRONMENT" has been designed in order to bring about an understanding on basic issues of Environment Ecology. This scenario has forced global leaders to find a balanced solution. INSTITUTION AND MEASURES 237-243 NATIONAL WIDE LIFE ACTION PLAN 237 NATIONAL AFFORESTATION AND ECO-DEVELOPMENT BOARD 237 CAMPA 238 JOINT FOREST MANAGEMENT 238 SOCIAL FORESTRY 239 NATIONAL BAMBOO MISSION 240 CEPI 240 LIGHTING A BILLION LIVES 240 ECO-MARK 241 USERS 241 BCRLIP 241 NATIONAL CLEAN ENERGY FUND 241 NATIONAL MISSION FOR ELECTRIC MOBILITY 242 SCIENCE EXPRESS .
The oldest continental crustal rocks on Earth have ages in the range from about 3.7 to 4.28 billion years  and have been found in the Narryer Gneiss Terrane in Western Australia, in the Acasta Gneiss in the Northwest Territories on the Canadian Shield, and on other cratonic regions such as those on the Fennoscandian Shield.
Some zircon with age as great as 4.3 billion years has been found in the Narryer Gneiss Terrane.
The primordial crust was very thin and was probably recycled by much more vigorous plate tectonics and destroyed by significant asteroid impacts, which were much more common in the early stages of the solar system. These issues are a major concern for policy makers across the world and more so in a developing. student community and the general public on Environment. The SHRNKRR KRS RCIRDEMY has left no stone unturned in bringing this edition on our environment. 231-236 WILD LIFE PROTECTION ACT 1972 231 ENVIRONMENTAL PROTECTION ACT 1986 232 NATIONAL FOREST POLICY 1988 233 BIOLOGICAL DIVERSITY ACT 2002 233 SCHEDULE TRIBES AND OTHER FOREST DWELLERS ACT 2006 234 COASTAL REGULATION ZONE 235 WETLAND RULES 2010 236 NATION GREEN TRIBUNAL 236 THE OZONE DEPLETING SUBSTANCES RULES 236 23.=.