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In this article, the author talks about freelance photographer, Arlene Edwards watching volcanic eruption from underneath Mount St. Helens in Washington on May 18, 1980 for predicting deadly eruptions. Topics discussed include seismic station around the mountain recording the trembling of earthquakes and jolts of buried explosives on distant shorelines, rock directly beneath Mount St. Helens too cold for producing magmas, and exceptionally dense material indicated from seismic waves.

The article discusses the connection between earthquakes and oil and gas production. Topics covered include the sixfold increase in earthquakes in the Dallas-Fort Worth (DFW) area in Texas, the observation by geologist David Evans that the volume and pressure of hazardous waste injections into the oil well at a chemical weapons plant outside Denver, Colorado corresponded with earthquake rates, and the rise of wastewater injection wells due to the emergence of horizontal drilling.

The article examines human-induced earthquakes. Particular focus is given to man-made solutions for these quakes. Additional topics discussed include the frequency of quakes in states including Oklahoma, Texas, and Kansas, how the quakes are caused by oil and gas production, and research from Stanford University.

The article discusses earthquake detection systems that can detect the earliest stages of an earthquake and sound an alarm to warn people of the danger. According to the author, earthquakes are unique natural disasters because they provide no warning before they strike. He notes that scientists have searched for precursory signs that would allow them to pinpoint where an earthquake will strike, but have yet to find any. Topics include how most traditional systems operate to detect earthquakes, the use of a network of seismometers to identify an earthquake's epicenter quickly, as well as improve predictions of a earthquake's magnitude, and a proposed statewide system in California, called the ShakeAlert System, that would help protect the population and business. INSET: Worldwide Warnings.

The article presents the discussion on innovations and discovery. Topics include helping seismologists finding the ways of discriminating between underground explosions and earthquakes; compressing the bellows forces air through an iron windpipe into an artificial glottis; and microscope discovered in the miasmatic air a multitude of living things.

This article discusses silent earthquakes. In early November 2000 the Big Island of Hawaii experienced its largest earthquake in more than a decade. Some 2,000 cubic kilometers of the southern slope of Kilauea volcano lurched toward the ocean, releasing the energy of a magnitude 5.7 shock. Part of that motion took place under an area where thousands of people stop every day to catch a glimpse of one of the island's most spectacular lava flows. Yet when the earthquake struck, no one noticed--not even seismologists. The chances of catastrophic flank failure are slim, and the instruments that record silent earthquakes might make early warnings possible. Kilauea's network of more than 20 GPS stations, for example, has already revealed that the volcano experiences creep, silent earthquakes as well as large, destructive typical earthquakes. Geologists have long known that water leaking into faults can trigger earthquakes, and nine days is about the same amount of time that they estimate it takes water to work its way down through cracks and pores in Kilauea's fractured basaltic rock to a depth of five kilometers-where the silent earthquake occurred. If future study reveals silent earthquakes to be a common feature of most large faults, then scientists will be forced to revisit long-held doctrines about all earthquakes.

For decades, earthquake experts dreamed of being able to divine the time and place of the world's next disastrous shock. But by the early 1990s the behavior of quake-prone faults had proved so complex that they were forced to conclude that the planet's largest tremors are isolated, random and utterly unpredictable. Most seismologists now assume that once a major earthquake and its expected aftershocks do their damage, the fault will remain quiet until stresses in the earth's crust have time to rebuild, typically over hundreds or thousands of years. At the heart of this hypothesis--known as stress triggering--is the realization that faults are unexpectedly responsive to subtle stresses they acquire as neighboring faults shift and shake. Drawing on records of past tremors and novel calculations of fault behavior, my colleagues and I have learned that the stress relieved during an earthquake does not simply dissipate; instead it moves down the fault and concentrates in sites nearby. Contradicting the nearly universal theory that major earthquakes strike at random was challenging from the start-especially considering that hundreds of scientists searched in vain for more than three decades to find predictable patterns in global earthquake activity, or seismicity. That big leap in probability explains why no one was initially surprised in June 1992 when a magnitude 6.5 earthquake struck near the southern California town of Big Bear only three hours after a magnitude 7.3 shock occurred 40 kilometers away, near Landers. By mapping the locations of Landers, Big Bear and hundreds of other California earthquakes, my colleagues and I began to notice a remarkable pattern in the distribution not only of true aftershocks but also of other, smaller earthquakes that follow a main shock by days, weeks or even years. INSETS: Forecasting under Stress;STRESSED OUT;EARTHQUAKE CLUSTERS.

Focuses on the occurrence of earthquakes in stable crust. Reasons for earthquakes away from familiar earthquake zones at the edges of tectonic plates; Tectonic activity driven by plate interactions.

Studies the occurrence of large earthquakes on blind faults under folded terrain in the U.S. Presence of an anticline reflects crustal compression; Features of the earthquakes in California; Factors causing the tendency of fault tips to propagate; Slow rupture time caused by the high fluid pressures registered in boreholes.

Examines the depths of earthquakes. International Seismological Centre's study of earthquakes; Impact of deep events in geophysics; Japanese seismologist Kiyoo Wadati's demonstration of the existence of deep events; Types of body waves; H.H. Turner's proposal that earthquakes occurred in three depth ranges.

Discusses the use of seismic tomography in analyzing earthquake waves. Facts about earthquake waves and how they behave; Categories of body waves; Velocity of shear and seismic waves; Development of detailed images of the earth's seismic-velocity structure through the application of tomography; Advantages of medical tomographers over seismologists.

The article determines the major earthquake zone along Mississippi embayment during the 18th century and early 19th century. It emphasizes that three of the greatest earthquakes in American history occurred hundreds of years ago near the loop of Mississippi River between the Kentucky and Missouri. There were major earthquakes happened in Ohio and Virginia.

The article discusses the evidence that will show the existence of methane on the gases released during earthquakes. One evidence is the presence of large concentration of dissolved methane in waters overlying on the plate boundaries and rift zones. Another evidence is the correlation between the major oil gas and gas regions and the primary zones of past and present seismic activity. It is noted that almost all known natural seeps of oil and gas are found along active or ancient fault lines.

The article provides information concerning the ground motion of the earthquakes. The way the ground is bent and the nature of the seismic waves that radiate during the earthquake provide basic information about the earthquake source. The location of an earthquake can be ascertained by a procedure akin to triangulation. The ground motions are influenced by the details of the rupture process, such as speed a the which the rupture travels over the fault surface.

The article focuses on the collision between the Indian subcontinent and the Eurasian land mass. Due to this collision, severe earthquakes and diverse land forms have risen. There are conjectures of continental drift that led to sea-floor spreading. The concept of plate tectonics provided a simple mechanism for large scale horizontal motion.

The article presents information on earthquake predication. Though short-term prediction could mobilize disaster-relief operation, a problem in earthquake predication is how one communicates to the public and the consequences of such warnings. With the advent of the theory of plate tectonics, the lithosphere is divided into a dozen plates that move with respect to one another.

The article describes quick clay as a natural aggregate made up of very fine mineral particles and water. Quick clay can be changed from solid to fluid by an earthquake, an explosion or even the jar of a pile driver. It will then flow rapidly along any slope or almost no slope at all. Quick clay can slide like an avalanche over flat land, with a slope of less than one degree, rafting along heavy structures in its path.

The article determines the composition of the earth's mantle that has an important function on tectonic process. In 1926, seismologist Beno Gutenberg attributed his observation that earthquake waves slow down when it travel through a zone approximately 100 to 200 kilometers below the surface of the earth, to a decreasing rigidity of the materials in the zone compared with what above and below it. Hugo Benioff, researcher at California Institute of Technology, has also studied several earthquakes in the Pacific Ocean, which led him to discover a remarkable indication of discontinuity at the level of top of the low-velocity zone.

The article focuses on the submarine mountain range running for 40,000 miles across the bottom of all the ocean and covering an area which is equal to all of the continents. The mid-ocean ridge is the locus of a crack in the crust that runs twice around the earth. Earthquakes of the mid-ocean rift occur at a depth of 30 kilometers below the earth's surface, while, deep earthquakes are associated with the area of seismic submarine trenches and island chains surrounding the Pacific Ocean.

The article discusses the study of seismologist about earthquake waves to record earth motions and features. Seismology measures the frequencies of earthquake waves in seconds per cycle. The long earthquake waves travel at .9 to 2.8 miles per second, they range in length from 10 miles up to the 8,000-mile length of the diameter of the earth.

The article presents how to build of conventional seismographs to record seismic events. It analyzes the recorded waves of the Aleutian quake in Hawaii from a seismograph created by A. E. Banks, owner of stationery store in Santa Barbara, California. Seismograph operates under Isaac Newton's first law, which states that a body freely suspended and at rest will remain in that position until something gives it a push.

The article focuses on the trenches of the Pacific Ocean which are clues to the history of the earth's crust. All deep trenches seem to be generally V-shaped in cross section. Direct exploration of the trenches is difficult because their depth and extreme narrowness present formidable obstacles. The zone of trenches is the scene of the earth's most intense earthquake activity which suggests that the seat of the trench-producing forces lies far below the earth's surface.

The article discusses on the importance of seismology in expounding human knowledge regarding the interiority the earth. Seismology deals with internal characteristics of the earth from the realm of wild speculation to the stage of scientific measurement. Through the combination of geological information about surface rocks, laboratory experiments on rocks, and several astronomical observations, seismology offers a foundation for learning about the various conditions in the deep interior of the earth.

The article focuses on seismic research for in Nepal concerning the lack of significant earthquakes in the western part of the country using sedimentary cores from the bottom of Rara Lake. It mentions concerns over the lack of significant earthquakes recorded in western Nepal since 1505 which suggested a catastrophic earthquake could occur in the near future. It states sediment cores found evidence of at least eight avalanches since 1505 which were likely caused by moderate to large earthquakes.

The article presents the scientists measuring ocean warming. Topics include warming contributes to sea-level rise, imperiling marine species, and influencing weather patterns; speeds of sounds producing by undersea earthquakes for detecting ocean warming over wider areas; and raising concerns about disturbing marine animals.

Reports on a drilling vessel constructed by Japan that is designed to bore through the earth's crust and into the mantle. Hopes to study the convection processes linked with tectonic plate motion and earthquakes; Comments from Asahiko Taira, director general of the Center for Deep Earth Exploration (CDEX) of the Japan Agency for Marine-Earth Science and Technology, on the dangers of living in one of the most geologically active places in the world. INSET: GOING DOWN FOR LIFE.

The article offers global news briefs. Wilbur Wright, a man who broke all the previous records because of a continuous flight he made at Auvours, France of 76.5 miles in 2 hours 9 minutes 33 seconds, at a speed of 35.5 miles per hour. A Stupendous earthquake hit Southern Italy and Sicily that destroyed a large number of lives. A successful use of the radiometer in detecting gas pressure of a 50 millionth of an atmosphere by James Dewar.

The article discusses the risk of earthquake-related dam bursts in the Himalayan Mountains. According to the author, Chinese and Indian dams in geologically active areas could cause significant damage if they experience failure during predicted earthquakes. It is suggested that both China and India have withheld information about the design and robustness of their dams. Other topics include corruption and the Tehri Dam in the Central Himalayas.

A map of California, illustrating how an earthquake early-warning system, called the ShakeAlert system, would work to protect individuals in California from earthquake hazards is presented, including diagrams showing the anatomy of an earthquake.

The article examines the effects and consequences of a major earthquake striking California. The article is part of a special section of the magazine in which factors of change concerning life on Earth are examined. A number of elements are explored including the likelihood of the region being struck by an earthquake by the year 2038, the loss of life such a seismic event would engender, and the impact that earthquake preparation has on California building codes. Geophysicist Robert Yeats of Oregon State University is quoted.

The article reports that researchers are looking into the seismic event that paved Venus over with lava 500 million years ago. The European Space Agency's Venus Express orbiter will detect low-frequency sound waves produced by quakes and amplified by the planet's dense atmosphere. Identifying venusquakes could help researchers determine the ages of various features on the planet.

The article focuses on seismologist Lucy Jones. The author reviews an interview conducted with Jones by the National Geographic Channel. It is the author's view that the media likes to contact Jones regarding natural disasters because she knows how to explain complicated geology and can soothe an anxious audience. The article includes comments regarding Jones's work from Tom Jordan, director of the Southern California Earthquake Center in Los Angeles, California.

This article focuses on the geographical effects of the December 2004 Indian Ocean tsunami. A year of death and destruction wreaked mostly by humans ended with nature flexing her own muscles, to terrifying effect. A section of the earth's crust hundreds of kilometers long tore off its moorings, slamming into the seawater above. The resulting tsunami traveled at 700 kilometers per hour to rear up like a hydra onto shores, sweeping away some 225,000 lives and millions of livelihoods across 12 nations. Now, scientists are scrutinizing the oceanic and island terrain to determine how the crust has changed and to gauge what further horrors the earth may have in store. At the same time the tsunami scoured the planet, the earthquake permanently altered its shape. The earthquake and its aftershocks changed the shape and orientation of virtually the entire Burma plate and the lands it supports. INSET: WHEN OLD WAYS TRUMP NEW WAYS.

The article offers information about various mechanisms used to reduce the impact of earthquakes on buildings. Earthquakes kill thousands of people and cause billions of dollars in damage every year. Mechanisms that actually reduce the shake from an earthquake are still relatively new as of 2004. The leading techniques try to absorb a lot of the ground motion energy so the building does not have to. That often means inserting heavy-duty fixtures between the building and its foundation, such as base isolators, viscous fluid dampers that operate like shock absorbers, or slide bearings that allow the building to sway instead of snap. A few researchers are examining novel technologies, such as actuators that would pull on tendonlike beams to counteract ground motion or electrorheological fluids in a foundation that would turn from liquid to gel to filter out shock waves. In 1999 the National Science Foundation launched the Network for Earthquake Engineering Simulation to research how best to protect structures against earthquakes. INSET: DID YOU KNOW….

The enormous earthquake in November 2002 along Alaska's Denali Fault buckled highways and shook the trans-Alaska oil pipeline. But the magnitude 7.9 shock also set off surprising swarms of small tremors thousands of kilometers to the south. All three quakes affected the same geothermal volcanic fields in Wyoming's Yellowstone National Park, Mount Rainier in Washington State, and several sites in California. Alaska's quake, which was centered about 283 kilometers (176 miles) northeast of Anchorage, sent out a train of seismic waves. In addition, the seismic waves might stir the magma enough to create new bubbles, notes geophysicist Emily E. Brodsky of the University of California at Los Angeles.

Reports on the shake testing of homes at the Powell Structural Research Laboratory in San Diego, California. Use of simulated earthquakes on wood-frame houses; Procedure of the test, including use of a shake table and a hydraulic ram; Statement that a large number of homes were built prior to the introduction of modern construction codes; Inadequacy of foundation anchoring and shear-resistant elements; Danger earthquakes pose to the structure known as the tuck-under apartment building.

Examines the role of stress-transfer analysis, a method used to detect earthquakes. Use of the method in the magnitude 7.4 earthquake in Turkey in 1999; How geologists follow progressing patterns of earthquakes in order to more accurately predict them; Role of United States Geological Survey scientists in predictions; Criticism of stress-transfer analysis.

Focuses on the radio waves that may have signalled the Loma Prieta earthquake in San Francisco Bay Area, California. Lack of premonitory tremors of the earthquake; Damages incurred from the earthquake.

Reports that an investigation into tree-rings provides evidence into an 1812 earthquake on the San Andreas Fault. Effect of an earthquake on trees living near it; Significance of these findings, which show the difficulty of predicting earthquakes based on such evidence; Details of the earthquake.

Reports that folds nears the earth's surface may regions in the United States threatened by earthquakes. Vertical fissures between crustal plates; Seismic data and measurements; Prediction of which folds may rupture.

Examines proposals for the development of programs and initiatives to protect people from natural disasters. Effects of volcanic eruptions, earthquakes and attacks of comets or asteroids; Overview of the Strategic Defense Initiative; Importance of international cooperation to protect the people against natural hazards.

The article discusses the Earthquake Hazards Reduction Act by the Federal Government in the U.S. The Act was prior to the fact that United States has many earthquake-prone places. The President in the U.S. will designate an agency to lead the coordination in the national programs and to work with the states in the mitigation activities under the plan.

A correction concerning the 2011 Tohoku, Japan, earthquake is provided to the article "Journey to the Bottom of the Sea" by Mark Schrope, which appeared in the April 2014 issue.