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The carbon dioxide cycle The carbon dioxide cycle

The seasonal CO2 cycle on Mars refers to the exchange of carbon dioxide between dry ice in the seasonal polar caps and gaseous carbon dioxide in the atmosphere. This review focuses on breakthroughs in understanding the process involving seasonal carbon dioxide phase changes that have occurred as a result of observations by Mars Global Surveyor.
Authors
Philip B. James, Gary B. Hansen, Timothy N. Titus

Ongoing hydrothermal heat loss from the 1912 ash-flow sheet, Valley of Ten Thousand Smokes, Alaska Ongoing hydrothermal heat loss from the 1912 ash-flow sheet, Valley of Ten Thousand Smokes, Alaska

The June 1912 eruption of Novarupta filled nearby glacial valleys on the Alaska Peninsula with ash-flow tuff (ignimbrite), and post-eruption observations of thousands of steaming fumaroles led to the name ‘Valley of Ten Thousand Smokes’ (VTTS). By the late 1980s most fumarolic activity had ceased, but the discovery of thermal springs in mid-valley in 1987 suggested continued cooling of...
Authors
N. Hogeweg, T. E. C. Keith, E.M. Colvard, S. E. Ingebritsen

The May 2003 eruption of Anatahan volcano, Mariana Islands: Geochemical evolution of a silicic island-arc volcano The May 2003 eruption of Anatahan volcano, Mariana Islands: Geochemical evolution of a silicic island-arc volcano

The first historical eruption of Anatahan volcano began on May 10, 2003. Samples of tephra from early in the eruption were analyzed for major and trace elements, and Sr, Nd, Pb, Hf, and O isotopic compositions. The compositions of these tephras are compared with those of prehistoric samples of basalt and andesite, also newly reported here. The May 2003 eruptives are medium-K andesites...
Authors
J.A. Wade, T. Plank, R. J. Stern, D.L. Tollstrup, J.B. Gill, J. C. O’Leary, J.M. Eiler, R. B. Moore, J.D. Woodhead, F. Trusdell, T.P. Fischer, David R. Hilton

Aeolian processes at the Mars Exploration Rover Meridiani Planum landing site Aeolian processes at the Mars Exploration Rover Meridiani Planum landing site

The martian surface is a natural laboratory for testing our understanding of the physics of aeolian (wind-related) processes in an environment different from that of Earth. Martian surface markings and atmospheric opacity are time-variable, indicating that fine particles at the surface are mobilized regularly by wind. Regolith (unconsolidated surface material) at the Mars Exploration...
Authors
R. Sullivan, D. Banfield, J.F. Bell, W. Calvin, D. Fike, M. Golombek, R. Greeley, J. Grotzinger, Kenneth E. Herkenhoff, D. Jerolmack, M. Malin, D. Ming, Laurence A. Soderblom, S. W. Squyres, S. Thompson, W.A. Watters, C.M. Weitz, A. Yen

Locations and descriptions of gravity, box, and push cores collected in San Francisco Bay between January and February, 1990 and 1991 Locations and descriptions of gravity, box, and push cores collected in San Francisco Bay between January and February, 1990 and 1991

A project to study San Francisco Bay sediments collected over 300 sediment gravity cores; six push cores, and three box cores in San Francisco Bay during the years 1990-91. The purpose of the sampling effort is to establish a database on the Holocene sediment history of the bay. The samples described and mapped are the first effort to catalog and present the data collected. Thus far the...
Authors
Roberto J. Anima, H. Edward Clifton, Carol Reiss, Florence L. Wong

Thermal observations of gas pistoning at Kilauea Volcano Thermal observations of gas pistoning at Kilauea Volcano

Data acquired by three continuously recording thermal infrared thermometers situated on the north rim of Pu'u'O' o Crater at Kilauea Volcano during 2002 revealed episodes of periodic thermal pulses originating from a degassing vent on the crater floor. These thermal pulses are interpreted as gas release (jetting events) associated with gas pistoning, a mechanism observed previously at...
Authors
J.B. Johnson, A.J.L. Harris, R. Hoblitt

An updated global earthquake catalogue for stable continental regions: Reassessing the correlation with ancient rifts An updated global earthquake catalogue for stable continental regions: Reassessing the correlation with ancient rifts

We present an updated global earthquake catalogue for stable continental regions (SCRs; i.e. intraplate earthquakes) that is available on the Internet. Our database contains information on location, magnitude, seismic moment and focal mechanisms for over 1300 M (moment magnitude) ≥ 4.5 historic and instrumentally recorded crustal events. Using this updated earthquake database in...
Authors
S.M. Schulte, Walter D. Mooney

The legacy of contaminated sediments in Boston Harbor The legacy of contaminated sediments in Boston Harbor

Scientists at the U.S. Geological Survey (USGS) have assembled a significant body of data that is now in a usable form. The USGS adopted an interdisciplinary approach to begin the pioneering effort at data rescue. This work involved collaboration with the Environmental Protection Agency (EPA), the U.S. Army Corps of Engineers (USACE), the Massachusetts Water Resources Authority (MWRA)
Authors
Frank T. Manheim

Book review: Earth’s magnetism in the age of sail Book review: Earth’s magnetism in the age of sail

For many centuries, the source, behavior, and even the essential nature of geomagnetism were enigmatic. Despite this, the effect of geomagnetism was familiar, by imparting a directional preference on the magnetized needle of the compass and providing a useful, if somewhat annoyingly complicated, reference for navigators. Although the compass seems to have first been invented in China, it...
Authors
Jeffrey J. Love

Evidence from Opportunity’s Microscopic Imager for water on Meridiani Planum Evidence from Opportunity’s Microscopic Imager for water on Meridiani Planum

The Microscopic Imager on the Opportunity rover analyzed textures of soils and rocks at Meridiani Planum at a scale of 31 micrometers per pixel. The uppermost millimeter of some soils is weakly cemented, whereas other soils show little evidence of cohesion. Rock outcrops are laminated on a millimeter scale; image mosaics of cross-stratification suggest that some sediments were deposited...
Authors
Kenneth E. Herkenhoff, S. W. Squyres, R. Arvidson, D.S. Bass, J. F. Bell, P. Bertelsen, B. L. Ehlmann, W. Farrand, Lisa R. Gaddis, R. Greeley, J. Grotzinger, A. G. Hayes, S.F. Hviid, J. R. Johnson, B. Jolliff, K.M. Kinch, A. H. Knoll, M.B. Madsen, J.N. Maki, S. M. McLennan, H.Y. McSween, D. W. Ming, J. W. Rice, L. Richter, M. Sims, P. H. Smith, Laurence A. Soderblom, Nicole Spanovich, R. Sullivan, S. Thompson, T. Wdowiak, C. Weitz, P. Whelley

Comments on potential geologic and seismic hazards affecting coastal Ventura County, California Comments on potential geologic and seismic hazards affecting coastal Ventura County, California

This report examines the regional seismic and geologic hazards that could affect proposed liquefied natural gas (LNG) facilities in coastal Ventura County, California. Faults throughout this area are thought to be capable of producing earthquakes of magnitude 6.5 to 7.5, which could produce surface fault offsets of as much as 15 feet. Many of these faults are sufficiently well understood...
Authors
Stephanie L. Ross, David M. Boore, Michael A. Fisher, Arthur D. Frankel, Eric L. Geist, Kenneth W. Hudnut, Robert E. Kayen, Homa J. Lee, William R. Normark, Florence L. Wong
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