A sequence of small earthquakes that occurred at the Dallas-Fort Worth Airport between October 30, 2008 and May 31, 2009 were likely triggered by the disposal of brines accompanying natural gas production at a nearby well that had recently been completed, according to research published in the February issue of the Bulletin of the Seismological Society of America (BSSA).
Many residents of the Dallas-Fort Worth area felt small earthquakes, which had magnitudes between 2.2 and 3.3, prompting scientists to investigate. The area, home to more than four million residents, had experienced no previous earthquakes in historic times. A significant increase since 2002 in the number of permits authorizing drilling and hydraulic fracturing to promote natural gas raised the possibility of induced earthquakes.
Researchers from University of Texas at Austin and Southern Methodist University analyzed data captured by regional and temporary seismic networks, which identified more than 180 earthquakes. Because of the absence of previous historical earthquakes, the proximity of the brine disposal well, and the similarity with other documented cases of induced seismicity in Texas, the authors suggest that the injected fluid migrated to a previously inactive fault, reactivating it.
The Dallas-Fort Worth Earthquake Sequence: October 2008 through May 2009, by Cliff Frohlich and Eric Potter of University of Texas at Austin; Chris Hayward and Brian Stump of Southern Methodist University.
Media contact: Cliff Frohlich, firstname.lastname@example.org, 512-471-0460
Identifying large hurricanes through seismology
Storm-generated seismic signals may allow seismologists to detect large hurricanes at sea and track their intensity, adding useful data to the discussion of whether anthropogenic global warming has increased the frequency and intensity of hurricanes and tropical storms, including ones that don't reach land.
Ambient noise, or microseisms, is the pervasive background signal bathing the surface of the Earth and is not produced by earthquakes. These surface waves generated by ocean storms are detected even in continental interiors far from source regions.
Researchers at Northwestern University demonstrate that the August 1992 category 5 Hurricane Andrew can be detected using microseisms recorded at the Harvard, Massachusetts seismic station, even while the storm is as far as 1200 miles away at sea. When applied to decades of existing analog seismograms, this methodology could yield a seismically identified hurricane record for comparison to the pre-aircraft and pre-satellite observational record.
Seismological Identification and Characterization of a Large Hurricane, by Carl W. Ebeling and Seth Stein of Northwestern University.
Media contact: Carl W. Ebeling, email@example.com, 847-467-1639
Southern San Andreas quake expected soon
The Coachella Valley section of the San Andreas fault, between San Gorgonio Pass and the Imperial Valley, is the only portion of the fault which has not ruptured in a major earthquake during historical time. New paleoseismic data suggests an average recurrence cycle of 116 to 221 years, indicating that it is past the expected time for a fault rupture.
Researchers from the University of Oregon and the U.S. Geological Survey have constructed an earthquake chronology for the past 1200 years for the southernmost San Andreas fault based on a new paleoseismic investigation conducted in the city of Coachella, California. Five to seven earthquakes were identified, with the last earthquake occurring at the site approximately 320 years ago. The interval since the last earthquake is as long or longer than every period of previous quiescence in the paleoseismic record.
This long period of quiescence suggests that an unusually large amount of elastic strain has built up along the southern San Andreas segment, making it likely to produce a large to great (Mw7-8) earthquake in the near future.
San Andreas Fault Earthquake Chronology and Lake Cahuilla History at Coachella, California, by Belle Philibosian of Caltech, Thomas Fumal of U.S. Geological Survey and Ray Weldon of University of Oregon.
Corresponding author: Belle Philibosian, firstname.lastname@example.org, 626-395-3811.
Nan Broadbent | EurekAlert!
Northern oceans pumped CO2 into the atmosphere
27.03.2017 | CAGE - Center for Arctic Gas Hydrate, Climate and Environment
Weather extremes: Humans likely influence giant airstreams
27.03.2017 | Potsdam-Institut für Klimafolgenforschung
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
27.03.2017 | Earth Sciences
27.03.2017 | Life Sciences
27.03.2017 | Life Sciences