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From Fires to Volcanoes: USGS at the American Geophysical Union 2004
Understanding and Reducing the Risks from Hazards

Released: 12/13/2004

Contact Information:
U.S. Department of the Interior, U.S. Geological Survey
Office of Communication
119 National Center
Reston, VA 20192
Catherine Puckett 1-click interview
Phone: 707-499-1210

Stephanie Hanna
Phone: 206-331-0335

AGU meets in San Francisco, California, from Dec 13-17, 2004. For information on any of these newstips, please call the contacts listed above.

MONDAY, December 13

Urban Development and Water Quality: USGS is studying urban basins in the Piedmont of North Carolina to determine the relation between urban development and water quality. Scientists collected data on water chemistry, hydrologic stage, discharge, water temperature, benthic algae, invertebrate and fish communities for 30 basins. They analyzed this data against an Urban Index that includes information about land cover, infrastructure, population, and socioeconomic characteristics. A preliminary review of the stream water-chemistry data indicates distinct relations between ionic composition and the Urban Index. Doug Harned (B11B-0150) and Thomas Cuffney (B11B-0146), Monday, 8:00 a.m.-noon, MCC Level 1

Press Conference: Landslides (on Land and Undersea) as a Source of Tsunamis: Evidence is accumulating that submarine and subaerial landslides pose a major tsunami hazard, particularly if the landslide is associated with oceanic volcanoes. In this press conference, scientists will discuss new research on Hawaiian Giant Submarine Landslides, including run-out modeling up to 2,600 feet above sea level. Monday, 2 p.m., Room 2012, Moscone West NOTE: This press conference is associated with Sessions OS21E-05, Peter Cervelli, 9 a.m., Tuesday (The Silent Earthquakes of Kilauea’s South Flank and Catastrophic Failure), MCC 3011, and OS23B (Tuesday 1:40 p.m.) MCC Level 2

TUESDAY, December 14

No Green Martians but Other Life on Mars? It’s Possible: The Mars rovers found evidence for water, not life. Yet in a column published Dec 3 in Science Magazine, USGS scientist Jeffrey Kargel noted that these rover missions, the European Space Agency’s discovery of methane on the planet, and other exciting finds have led to the conclusion that Mars surely was, and most likely still is, a water world and may have been or perhaps still is a living world. The planet clearly possessed a potentially habitable environment at Meridiani Planum. Fine, rhythmic layers, polygonal cracks, and other features observed by the Opportunity rover resemble similar features normally found in wet sedimentary environments on Earth. The mineralogical characteristics further specify a highly acidic watery environment on Mars. The presence of methane is consistent with the possible current existence of subsurface life. Because of this possibility, Kargel noted that future exploration of the planet must be approached with redoubled caution. "We are dealing with a whole new planet," says Kargel, "and it is one that has been isolated from Earth since the origin of the Solar System." Because of this, researchers, engineers, and policy makers must thoroughly review and test planetary protection methods that have been adopted to safeguard both Earth and Mars from biological contamination from each other. Kargel says, "Because of the possibility of life on Mars, the issues of safety for both planets are the ultimate reason to ensure that we do not short-circuit planetary protection techniques." The possibility of life on Mars is also a prime motivation to proceed with exploration of Mars. Jeffrey Kargel (P21A-0205), Tuesday, 8 a.m., MCC Level 1

PAGER: Prompt Assessment of Global Earthquakes for Response: A combined death toll of 30,000 for the earthquakes in Iran (2003), Algeria (2003), and Morocco (2004) stresses the importance of improving the world’s ability to respond to and mitigate earthquake disasters. At present, it takes several hours to days for the media and other organizations to provide an assessment of a damaging earthquake, an unacceptable delay when rapid mobilization of rescue and aid workers can save lives. To reduce this delay, USGS scientists at the National Earthquake Information Center, in cooperation with U.S. Agency for International Development, are developing a system to rapidly assess societal impact immediately after significant global earthquakes. The system, called PAGER (Prompt Assessment of Global Earthquakes for Response), will rapidly and accurately assess the severity of damage caused by an earthquake and alert emergency responders, government agencies, and the media to the scope of the potential catastrophe. The system is triggered by real-time earthquake locations from the USGS and supplies its users with valuable information beyond location and magnitude to help emergency agencies mount effective responses. When applied in a non-real-time mode to scenario earthquakes, PAGER can identify populations of the world that are highly susceptible to earthquake-induced devastation and provide motivation to improve their earthquake resistance. Paul Earl (S21A-0259), 8 a.m., Tuesday, MCC Level 1

Seasonal Earthquake Activity Associated with Active Volcanoes in the Western United States: USGS scientists have examined volcanic areas in the western United States for evidence of seasonal earthquake activity by studying data sets covering a 20-year period for the large caldera areas of Long Valley caldera and Yellowstone National Park, and the Cascade Range stratovolcanoes: Mts Lassen, Hood, St. Helens, and Rainier. The scientists developed a method to identify and remove large earthquake swarm events associated with magmatic intrusion to better detect annual seasonal trends and to test for annual seismic patterns associated with seasonal changes. Seven of the ten study areas show statistically significant seasonality, with exceptions in two Long Valley Caldera study areas and at Mount St. Helens. Elsewhere in the Cascade Range and in the other Long Valley study area peaks in annual seismicity occur in the late summer and autumn, whereas in Yellowstone National Park seismicity peaks earlier during late spring and summer. Possible mechanisms that could induce seasonal seismicity in these areas include barometric pressure changes, solid earth tides, snow unloading (associated with annual snowmelt), and groundwater recharge processes; the most probable triggers are snow unloading and groundwater recharge. Lizet Christiansen (S21B-0276), Tuesday, 8 a.m., MCC Level 1

Arsenic and Old Bugs? The rapidly growing suburbs west of Washington, D.C. once were covered by apple orchards that farmers sprayed with lead- and arsenic- based pesticides. These chemicals are now a source of arsenic in agricultural soil and in groundwater in the Mid-Atlantic region. After feeding on plant roots underground for 17 years, Brood X cicadas emerged at densities of 30,000 or more individuals per hectare throughout the area. With a very limited dispersal, even as adults, could they be a monitor for local contamination? If they contain arsenic, could cicadas be a threat to birds and other wildlife that feed on them? Rob Robinson (H21C-1034), Tuesday, 8 a.m., MCC Level 2

Southern California Earthquake Likelihood Models: Recent scientific studies have demonstrated that dramatic improvements in seismic hazards analysis will require an approach based more on the input of physics into the system being used for creating models. At the same time, however, proper seismic hazards analysis requires that all kinds of viable models be included. To meet these challenges, the Southern California Earthquake Center (SCEC) has established a working group to develop a variety of Regional Earthquake Likelihood Models for different areas which involve highly possible fault rupture scenarios. Earthquake models under development range from simple ones (based on smoothed historical seismicity) to sophisticated ones that use physical earthquake simulators that track stress changes throughout a particular system. The earthquake-rupture forecast models will be tested against available geophysical observations and will evaluate the seismic hazard implications in the related geographic areas. One example of a model is the SCEC Earthquake Rupture Forecast, which will be a logical extension of the consensus models developed by previous Working Groups on California Earthquake Probabilities. This model will be improved to allow various components to be added when available, and will be entirely flexible to account for the influence of any significant seismic events in real-time. Edward (Ned) Field (S21C), Tuesday, 8 a.m., MCC 3006

Press Conference: Update on the Continuing Eruption of Mount St. Helens: Mount St. Helens in southwest Washington state reawakened in late September with earthquake swarms, localized ground deformation and several explosions, which continued through mid-October. Now the volcano has settled into a prolonged period of lava-dome growth. The news conference will highlight key aspects of the eruption, including new information about the lava and earthquake patterns and discussion of new methods and innovative tools to monitor the eruption. The new lava dome’s location, mode of growth and hazards prompted development of new monitoring tools, including packages of instruments that can be slung in by helicopter and do not require on-the-ground installation, a first in monitoring erupting volcanoes. Scientists also will discuss increasing risks as winter snowpack builds up in the crater and the dome continues to grow. Continued growth increases the risk of partial dome collapse, which could trigger moderate explosions and possibly significant lahars (volcanic mudflows) from the crater. USGS and University of Washington, Tuesday, 2 p.m., Moscone West, Room 2012 NOTE: This press conference is associated with Mount St. Helens special session V31E, Seth Moran et al, Wednesday, 8 a.m. to noon, MCC3009

Kilauea’s Silent Earthquakes and Their Possible Link to Catastrophic Slope Failure: The south flank of Kilauea volcano is one of the most actively deforming regions on the planet. GPS measurements taken since the early 1990s show a persistent seaward migration at rates exceeding 5 centimeters per year, and large earthquakes occur there with alarming frequency. In the last few years an intermediate form of south flank deformation has been observed that results in slip rates of about 10 centimeters per day. This type of deformation is attributed to "silent earthquakes" which are much slower to cause displacement than the nearly instantaneous brittle failure of normal earthquakes, but vastly faster than the creep that moves the south flank of Kilauea relentlessly toward the sea. Offshore, numerous submarine debris fields are thought to represent ancestral flank collapses of the volcano. If these collapses were to have occurred catastrophically, they almost certainly would have created tsunami events large enough to inundate nearby islands and perhaps affect coastal areas around the Pacific basin. Prehistoric evidence of such inundation consists of anomalously elevated coral deposits at several locations, interpreted as having resulted from a tsunami wave. Kilauea, being the youngest and most active Hawaiian volcano, is a likely suspect for future catastrophic slope collapses. Network deformation monitoring has detected several silent earthquakes creating elastic deformation fields large enough to model. The modeling shows that these events occurred as part of a structure that can be plausibly interpreted as one that accommodates gravity-driven block rotation and could account for the steady creep rate and occasional large earthquakes. If so, the current active deformation within Kilauea’s south flank probably promotes stability rather than catastrophe and is not a likely location for catastrophic or even large flank collapse at its current stage of growth. Peter Cervelli (OS21E-05), 9 a.m., Tuesday, MCC 3011


Mount St. Helens Special Session V31E, 8 a.m. to noon, MCC3009 (for more information, see "press conference tip" from Tuesday).

Newly Recognized Santa Clara Valley Faults and Earthquake Hazards: USGS scientists, using combined subsurface reflection and refraction imaging from the San Andreas Fault to the central Santa Clara Valley, have identified complex structures associated with Santa Cruz Mountains tectonics that have a rather dramatic influence on the western Santa Clara Valley. Seismic imagery shows numerous faults within the Santa Cruz Mountains that are consistent with surface geologic mapping and are interpreted as being steeply dipping features within basement rocks in the Santa Cruz Mountains. Within the Santa Clara Valley, the imagery suggests that multiple faults lie beneath the alluvium of the western Santa Clara Valley, and recorded earthquakes over the past 30 years provide documentation that these faults are considered to be still active. Some of these faults extend to relatively shallow depths of around 20 meters, which includes the base of the groundwater aquifer system, suggesting at least post-Pliocene movement on faults at shallow depths. Imaging appears to show that the principal fault zone beneath the western Santa Clara Valley is about six kilometers wide in the uppermost crust but tapers to about 4 km in width at 5 km depth, as observed in other known structures in similar environments. The high population density within the Santa Clara Valley and the proximity of these buried faults makes the earthquake hazard in the western portion of the Valley potentially high. This potential hazard is compounded by the thick sequence of sediments within the Cupertino Basin that can amplify seismic waves generated by movement on regional and/or local faults. Rufus Catchings (S-31A-1031), Wednesday, 8 a.m., MCC Level 2

William T. Pecora Awards: This award is presented annually to recognize outstanding contributions by individuals or groups toward understanding the earth by means of remote sensing. USGS scientist Wayne Thatcher will receive the Charles A. Whitten Medal - For outstanding achievements in research on the form and dynamics of the Earth and planets. This award is presented not more often than every other year in odd-numbered years. Sponsored by the U.S. Department of the Interior and the National Aeronautics and Space Administration., 6:30 p.m., Wednesday, San Francisco Marriott Hotel (open to all registrants)


Assessing Southern California Post-Wildfire Debris-Flow Hazards: The increased incidence of catastrophic wildfires in the western United States, as well as the increasing encroachment of development into fire-prone ecosystems, have created a critical need for new and improved methods to quantify potential hazards posed by debris flows produced from burned watershed areas. Such debris flows are one of the most hazardous consequences of rainfall on recently burned hillsides. Statistical models developed to estimate the probability and magnitude of post-wildfire debris flow activity were used to generate debris flow hazard maps for watershed basins burned by the devastating October 2003 southern California wildfires. Probability maps describe the chance of debris-flow production from an individual basin as a function of area burned, soil properties, basin gradients, and total storm rainfall. Peak discharge maps estimate debris-flow peak discharge at a drainage basin outlets as a function of basin gradient, area burned, and storm rainfall totals. Together, these maps identify those drainage basins that are most prone to large debris-flow events and provide information for mitigation and evacuation planning. Evaluation of the response to the Christmas Day, 2003 rainstorm event that triggered debris flows and flooding from recently burned basins allows for an assessment of the mapping approach effectiveness and provides guidance for refinement of future watershed modeling. Susan Cannon (H43G-05), Thursday, 2:40 p.m., MCC 3005

Earlier Spring Blooms in the Western United States: a harbinger of large-scale climate change? USGS scientists, together with partners from the University of Utah and Montana State University, have documented the advanced onset of spring over a broad region of the western United States since the late 1970s. Scientific studies measuring the timing of snowmelt runoff from seasonal snowpack areas in the Sierra Nevada mountain range and elsewhere, together with annual observations of the onset of the first spring blooms of lilac and honeysuckle, indicate that the onset of spring has advanced by about one to three weeks in many areas throughout the western United States. The scientists have documented that fluctuations in lilac and honeysuckle bloom dates have a high correlation with similar fluctuations in the spring snowmelt pulse, and that anomalous temperatures exert the greatest influence upon changes in the onset of spring within these measurable networks. Earlier spring onsets since the late 1970s are a remarkable feature in the climate records and reflect the unusual spell of warmer-than-normal springs in western North America during this period. Such observations of evidence for warmer springs may point to a relationship between these recorded measurements and large-scale climate change. Daniel Cayan (B41A-0098), Thursday, 8 a.m., MCC Level 1

Keeping an Eye on the Three Sisters: Just down the road a bit from Mount St. Helens, the Three Sisters volcanic center had been quietly and unobtrusively inflating since somewhere between the summers of 1996 and 1998. The most likely cause of this growth is a pulse of magma intrusion into the upper crust at a depth between 2.5 and 5.5 miles. In 2001, however, USGS scientists used a specialized kind of radar called InSAR that detected the deformation, which most likely would have otherwise escaped notice unless accompanied by an unusual amount of seismicity. InSAR, or interferometric synthetic aperture radar, allows researchers to peer beneath the earth’s surface in their mind’s eye by mapping subtle movements of the ground surface. The new technique is proving an essential tool in the kit of volcanologists. The deformation is centered about 3 miles west of the summit of South Sister, which last erupted between 2,200 and 2,000 years ago. The deforming area is about 12 miles in diameter and extends across much of the western part of the Three Sisters Wilderness. In March 2004, more than 300 small, shallow volcano-tectonic earthquakes (up to magnitude 1.9) occurred in the northeast part of the deforming area; it was the first notable seismicity in the area for more than two decades. The likelihood that the current episode at Three Sisters will culminate in an eruption in the near term is low, but the impact of an eruption could be great because the area is one of the most popular wilderness destinations in the western United States and the potential hazards from lahars (volcanic mudflows) and ash fall extend beyond the wilderness boundaries. In response to the unrest, a volcano hazard assessment has been completed, safety and other concerned agencies and the public have been notified, and an emergency coordination and communications plan is being prepared to use in the event of an eruption. Daniel Dzurisin (G42A-04), Thursday, 11:15 a.m., MCC 3010

Press Conference: The Best-Instrumented Earthquake Ever: The September 28, 2004, Parkfield Earthquake: One of the most significant earthquakes in the history of seismology struck along the San Andreas Fault in central California on the morning of September 28, 2004. The data that was captured for this strong magnitude 6.0 earthquake is advancing the understanding of how earthquakes occur, cause damage, and perhaps may help reveal if earthquakes can be predicted in the future. The Parkfield earthquake had been anticipated by the U.S. Geological Survey, California Geological Survey and their partners in 1984, and instrumentation had begun in 1986. The coordinated efforts of these partners led to a dense network of instruments poised to capture anticipated earthquakes and reveal the earthquake process in unprecedented detail. Located just 3 miles northwest of the Parkfield 2004 rupture, the San Andreas Fault Observatory at Depth (SAFOD) is a component of the National Science Foundation’s Earthscope Project. Participants in this press conference will discuss some of the spectacular data obtained from the Parkfield 2004 earthquake. USGS; University of California, Berkeley; California Geological Survey, Thursday, 1 p.m., Moscone West, Room 2012

NOTE: This press conference is associated with sessions:
S51C, Friday, 8 a.m., MCC Level 1
S53D, Friday, 1:40 p.m., MCC 3001
S54B, Friday, 4:00 p.m., MCC 3001
Animal Farm:
U.S. animal agriculture has undergone major changes. Although the total livestock population has remained relatively unchanged, the number of producers has declined dramatically, and the average size of the remaining operations has increased substantially. A pronounced trend toward spatial concentration of farm animals is the result. These changes raise important questions about the overall national effects on water quality. Richard Smith (H43B-0371), Thursday, 1:40 p.m. to 5 p.m., MCC Level 1

FRIDAY, December 16

Checking Up on Puerto Rico’s Reefs: Sediment and nutrient discharge have likely contributed to widespread degradation of Puerto Rico’s coral reefs during the past century. Sediment deposition reduces the area of sea floor suitable for growth of new coral, diminishes the amount of light available, and in extreme cases, buries coral colonies. Better land management has significantly improved the quality of water since the 1980s. Nitrogen and phosphorous concentrations in river waters are now well within regulatory limits, although current concentrations are as much as 10 times the estimated pre-settlement levels. Concentrations of pathogens also are improved but continue to be near or above regulatory limits. Matt Larsen (H51C-1133), Friday, 8 a.m. to noon, MCC Level 2

3-D Hayward Fault Geology and Its Influence on Fault Behavior: USGS scientists have studied the relationships between fault behavior and geology along the Hayward Fault using a three-dimensional geologic model of the Hayward Fault and vicinity. The model, derived from geologic, geophysical, and seismicity data, has provided the necessary information to construct the relationships between geologic units on both sides of the surface trace of the fault, providing maps of units that truncate against the fault surface. The geologic maps that resulted were compared with seismic data and documented creep measurements using 3-D visualization software. The seismic behavior of the Hayward Fault correlates well with rock unit contacts along the fault, rather than in rock types across the fault. This suggests that fault activity is, in part, controlled by the physical properties of rocks abutting against the fault plane and not by properties of the fault zone itself. Preliminary study results comparing fault behavior with the inferred three-dimensional geology adjacent to the Hayward Fault suggests that any attempt to understand the detailed distribution of earthquakes or creep along the fault should include consideration of the rock types abutting against the fault surface, and would benefit greatly from incorporating the physical properties of rock types along the fault into the three-dimensional geologic model. The scientists provide examples of fault behavior along different segments of the Hayward Fault and explain the correlation to the local geology. David Ponce (S51A-0132), Friday, 8 a.m., MCC Level 1

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