Seismicity changes associated with the 2000 earthquake swarm in the Izu Island region

Abstract During the summer of 1993, the residents in the Norris Lake community, Lithonia, Georgia, were bothered by an incessant swarm of earthquakes. The largest, a magnitude 2.7 on September 23, showed a normal aftershock decay and occurred after the main swarm. Over 10,000 earthquakes have been detected, of which perhaps 500 were felt. The earthquakes began June 8, 1993, with a 5-day swarm. The residents, accustomed to quarry explosions, suspected the quarries of irregular activities. To locate the source of the events, a visual recorder and a digital event recorder were placed in the epicentral area. Ten to 20 events were detected per day for the next three weeks. The swarm then escalated to a peak of over 100 per day by August 15, 1993. Activity following the peak died down to about 10 events per day. The magnitude 2.7 event of September 23 was followed by a normal aftershock sequence. The larger events were felt with intensity V within 2 km of their epicenter, and noticed (intensity II) to a distance of 15 km. Some incidents of cracked wallboard and foundations have been reported, but no significant damage has been documented. Preliminary locations, based on data from digital event recorders, suggest an average depth of 1.0 km. The hypocenters are in the Lithonia gneiss, a massive migmatite resistant to weathering and used locally as a building stone. The epicenters are 1 to 2 km south-southwest of the Norris Lake Community. The cause of the seismicity is not yet known. The earthquakes are characteristic of reservoir-induced earthquakes; however, Norris Lake is a small (96 acres), 2 to 5m deep recreational lake which has existed since the 1950s.

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Wildlife Use of Drainage Structures Under 2 Sections of Federal Highway 2 in the Sky Island Region of Northeastern Sonora, Mexico

Air Soil and Water Research ◽

10.1177/1178622120988721 ◽

2021 ◽

Vol 14 ◽

pp. 117862212098872

Author(s):

Mirna Manteca-Rodríguez ◽

Ricardo E Félix-Burruel ◽

Cecilia Aguilar-Morales ◽

Juan Carlos Bravo ◽

Myles Traphagen ◽

...

Keyword(s):

Quality Index ◽

Black Bear ◽

Island Region ◽

Wildlife Use ◽

Field Assessment ◽

Federal Highway ◽

Wildlife Migration ◽

Trail Cameras ◽

Sky Island ◽

Wildlife Mortality

Roads and highways are 1 of the most significant obstacles affecting wildlife movement by fragmenting habitat, altering wildlife migration and use of habitat, while also being a danger to wildlife and humans caused by wildlife-vehicle interactions. To mitigate wildlife mortality on highway sections and to minimize death and injury to motorists as well, road ecologists have proposed structures adapted for the safe passage of wildlife across roads. In this study, photographic sampling was conducted using trail cameras to quantify wildlife activity and use of existing culverts, bridges, and drainages within 2 separate sections of Mexico Federal Highway 2 where previous field assessment had observed high levels of activity. These sections are important areas for the conservation of wildlife, and they are known to be biological corridors for rare species of concern such as jaguar, black bear, and ocelot. The trail cameras were operated for 1 year to document the annual cycle of wildlife movement through the area. With the photographs obtained, a database was created containing the information from each wildlife-culvert interaction. Prior to sampling, an inventory of existing culverts was conducted that measured height, width, volume, and surrounding habitat to assign a hypothesized use quality index. After testing for significant differences in use index among culverts, we recognized that all culverts were equally important for moving wildlife, and that there were no significant differences in the use of culverts by the quality index.

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Protected areas and extractive hegemony: A case study of marine protected areas in the Qikiqtani (Baffin Island) region of Nunavut, Canada

Geoforum ◽

10.1016/j.geoforum.2021.01.011 ◽

2021 ◽

Vol 120 ◽

pp. 208-217

Author(s):

Warren Bernauer ◽

Robin Roth

Keyword(s):

Protected Areas ◽

Marine Protected Areas ◽

Baffin Island ◽

Island Region

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Analyzing Meteorological and Chemical Conditions for Two High Ozone Events Over the New York City and Long Island Region

IGARSS 2020 - 2020 IEEE International Geoscience and Remote Sensing Symposium ◽

10.1109/igarss39084.2020.9324470 ◽

2020 ◽

Author(s):

Yuhong Tian ◽

Margaret LaFarr ◽

Jeongran Yun ◽

Kevin Civerolo ◽

Winston Hao ◽

...

Keyword(s):

New York ◽

New York City ◽

York City ◽

Long Island ◽

Island Region ◽

Chemical Conditions

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Reflections on the L’Aquila trial and the social dimensions of disaster risk

Disaster Prevention and Management An International Journal ◽

10.1108/dpm-01-2018-0030 ◽

2019 ◽

Vol 28 (4) ◽

pp. 434-445 ◽

Cited By ~ 4

Author(s):

Angelo Jonas Imperiale ◽

Frank Vanclay

Keyword(s):

Local Community ◽

Social Issues ◽

Local Level ◽

Earthquake Swarm ◽

Disaster Risk ◽

Community Empowerment ◽

Court Case ◽

Civil Protection ◽

Content Type ◽

The Social

Purpose The purpose of this paper is to reflect on what can be learned about disaster risk reduction (DRR) from the L’Aquila trial of scientists. The court case was initiated because of a controversial meeting on 31 March 2009 of the Major Risks Committee (MRC), held under the auspices of the Italian Department of Civil Protection. The purpose of the meeting was to consider (prior to the fatal earthquake of 6 April 2009) disaster risk in the L’Aquila area, which was being affected by an earthquake swarm since October 2008. Design/methodology/approach The authors undertook a document analysis of trial materials, and a review of academic and media commentary about the trial. Findings The legal process revealed that disaster governance was inadequate and not informed by the DRR paradigm or international guidelines. Risk assessment was carried out only in a techno-scientific manner, with little acknowledgement of the social issues influencing risks at the local community level. There was no inclusion of local knowledge or engagement of local people in transformative DRR strategies. Originality/value Most previous commentary is inadequate in terms of not considering the institutional, scientific and social responsibilities for DRR as exposed by the trial. This paper is unique in that it considers the contents of the MRC meeting as well as all trial documents. It provides a comprehensive reflection on the implications of this case for DRR and the resilience of peoples and places at risk. It highlights that a switch from civil protection to community empowerment is needed to achieve sustainable outcomes at the local level.

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The Extreme Wind Events in the Ross Island Region of Antarctica

Weather and Forecasting ◽

10.1175/waf-d-15-0125.1 ◽

2016 ◽

Vol 31 (3) ◽

pp. 985-1000 ◽

Cited By ~ 1

Author(s):

Nicholas J. Weber ◽

Matthew A. Lazzara ◽

Linda M. Keller ◽

John J. Cassano

Keyword(s):

Structural Damage ◽

Ross Sea ◽

Enso Event ◽

Central Pacific ◽

Island Region ◽

Back Trajectories ◽

Extreme Wind ◽

Mcmurdo Station ◽

Wind Events ◽

Upper Level

Abstract Numerous incidents of structural damage at the U.S. Antarctic Program’s (USAP) McMurdo Station due to extreme wind events (EWEs) have been reported over the past decade. Utilizing nearly 20 yr (~1992–2013) of University of Wisconsin automatic weather station (AWS) data from three different stations in the Ross Island region (Pegasus North, Pegasus South, and Willie Field), statistical analysis shows no significant trends in EWE frequency, intensity, or duration. EWEs more frequently occur during the transition seasons. To assess the dynamical environment of these EWEs, Antarctic Mesoscale Prediction System (AMPS) forecast back trajectories are computed and analyzed in conjunction with several other AMPS fields for the strongest events at McMurdo Station. The synoptic analysis reveals that McMurdo Station EWEs are nearly always associated with strong southerly flow due to an approaching Ross Sea cyclone and an upper-level trough around Cape Adare. A Ross Ice Shelf air stream (RAS) environment is created with enhanced barrier winds along the Transantarctic Mountains, downslope winds in the lee of the glaciers and local topography, and a tip jet effect around Ross Island. The position and intensity of these Ross Sea cyclones are most influenced by the occurrence of a central Pacific ENSO event, which causes the upper-level trough to move westward. An approaching surface cyclone would then be in position to trigger an event, depending on how the wind direction and speed impinges on the complex topography around McMurdo Station.

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