Few subjects in the Earth sciences are as fascinating to the public as dinosaurs. The study of dinosaurs stretches our imaginations, gives us new perspectives on time and space, and invites us to discover worlds very different from our modern Earth. 

From a scientific viewpoint, however, the study of dinosaurs is important both for understanding the causes of past major extinctions of land animals and for understanding the changes in biological diversity caused by previous geological and climatic changes of the Earth. These changes are still occurring today. A wealth of new information about dinosaurs has been learned over the past 30 years, and science's old ideas of dinosaurs as slow, clumsy beasts have been totally turned around. We have learned answers to some frequently asked questions about dinosaurs, with current ideas and evidence to correct some long-lived popular misconceptions. Although much has been discovered recently about dinosaurs, there is still a great deal more to learn about our planet and its ancient inhabitants.

Diamond may well be the world's most versatile engineering material as well as its most famous gemstone.  The superiority of diamond in so many diverse industrial applications is attributable to a unique combination of properties that cannot be matched by any other material.  For example, diamond is the strongest and hardest known material and has the highest thermal conductivity of any material at room temperature.  Diamond that does not meet gem-quality standards for color, clarity, size, or shape is used principally as an abrasive, and is termed "industrial diamond."  Even though it is more expensive than competing abrasive materials, diamond has proven to be more cost effective in numerous industrial processes because it cuts faster and lasts longer than any rival material.  Synthetic industrial diamond is superior to its natural diamond counterpart because it can be produced in unlimited quantities, and, in many cases, its properties can be tailored for specific applications.  Consequently, manufactured diamond accounts for more than 90% of the industrial diamond used in the United States. 

Presently, glaciers occupy about 10 percent of the world's total land area, with most located in polar regions like Antarctica and Greenland. Glaciers can be thought as remnants from the last Ice Age, when ice covered nearly 32 percent of the land, and 30 percent of the oceans. An Ice Age occurs when cool temperatures endure for extended periods of time, allowing polar ice to advance into lower latitudes. For example, during the last Ice Age, giant glacial ice sheets extended from the poles to cover most of Canada, all of New England, much of the upper Midwest, large areas of Alaska, most of Greenland, Iceland, Svalbard and other arctic islands, Scandinavia, much of Great Britain and Ireland, and the northwestern part of the former Soviet Union.

GOLD

Gold is a gleaming symbol of California's bounty and wealth. It was the lure, the promise of California for hundreds of thousands of argonauts who overwhelmed California during the Gold Rush. Gold unleashed the forces that rocketed California to immense growth and development. It sparked a swirl of hopes and dreams, myths and legends, contributions and conflicts. 

But the legacies of the Gold Rush are complex--sometimes triumphant, sometimes troubled. It what seemed the blink of an eye, California's first people were overrun by a world rush. Miners saw nature as a force to be overcome to get at the golden treasure. Other rushes followed gold: agriculture, oil, real estate, motion pictures, military industry, computers. California became the nation's industrial, agricultural, and population leader. But the bounty and beauty of the region have paid a price for these achievements. The scales have not always been balanced. Immigrants still come, but the gold they seek is mostly metaphorical; not precious metal but opportunity.