I have organized my three papers. These are in a state of flux and I hope to submit them to my committee shortly.
Here is the draft of my first paper, I will be submitting this to Geosphere shortly. Here is a direct link to the pdf:
Here is my second paper. Here is a direct link to the pdf:
Here is the draft of my third paper, I will be submitting this to Geophysical Journal International shortly. Here is a direct link to the pdf:
Monthly Archives: August 2013
M 7.0 on the Aleutian subduction zone
Here is another pretty big earthquake. Those on the islands of Adak and Atka probably got shook pretty strongly.
The moment tensor shows a compressional earthquake and this is consistent with this setting on a subduction zone. If this EQ lies on the subduction zone fault, then it shows the dip of the subduction zone is about 22 degrees +-.
here is a map
Here is a cool animation for the earthquake from NOAA PMEL. This earthquake is highly unlikely to generate a tsunami, but these scientists do this for all earthquakes that could generate a tsunami.
http://earthjay.com/earthquakes/20130830_aleutians/andr1.mpeg
here is a map with the USGS shakemap overlay:
here is a map with historic earthquakes plotted as grey circles:
Here is the USGS page: http://earthquake.usgs.gov/earthquakes/eventpage/usb000jdt7#summary
Here is the USGS map for the region:
This is a map of modeled tsunami sea surface elevations.
People have been promoting ignorance and I am exhausted at explaining to each of them regarding this.
The ongoing nuclear disaster at Fukushima Power Plant in northeast Japan is horrible. However, we as a society could want to be the most well informed we can about those things that matter to us most, whatever those things might be. People have been using the wrong map as a graphic to show radiation spread across the Pacific. There is no such map. There are maps of ocean circulation model derived estimates of radiation. BUT there are no maps that actually show radiation floating across the Pacific. They do not exist.
Here is a great source of information for the ongoing nuclear disaster in northeast Japan: National Geographic
Here are the data from northeast Japan and from Fukushima itself, unabated by political or corporate filtering.
IAEA FMD
Here are the IAEA reports regarding Fukushima.
IAEA Fukushima Disaster
People have been using a map that shows potential sea surface elevations as a result of the subduction zone earthquake offshore Japan on 11 March, 2011. People make the claim that this is a map of radiation. Please do not be so ignorant to share this facebook post. We must have higher standards than this.
I memed up this graphic to help inform those who do not know what this map really is. Here it is:
Here is their source web page:
http://nctr.pmel.noaa.gov/honshu20110311/
Here is the original as provided by NOAA:
Here is a “Travel Time” map for the Tohoku-Oki Tsunami:
http://www.ngdc.noaa.gov/hazard/honshu_11mar2011.shtml
Here is that map of Travel Time for the Tohoku-Oki Tsunami:
Here is another original as provided by NOAA:
Here is the reddit page where someone posted my image.
Here is the imgur page where someone posted my image.
Latest Paper on Cascadia Seismoturbidites is now released
Our paper has recently been published online and open source. Please find this here.
This paper is part of a Natural Hazards and Earth System Sciences special issue on submarine paleoseismology.
Spatially Limited Mud Turbidites on the Cascadia Margin: Segmented Earthquake Ruptures?
C. Goldfinger1, A. E. Morey1, B. Black1, J. Beeson1, C. H. Nelson2, and J. Patton1
1Oregon State University, College of Oceanic and Atmospheric Sciences, 104 Ocean Admin. Bldg., Corvallis, Oregon 97331, USA
2Instituto Andaluz de Ciencias de la Tierra (IACT), CSIC-Univ. de Granada, Campus de Fuentenueva s/n, 18002 Granada, Spain
Abstract. A series of 23 thin, mostly mud-silt turbidites are found interspersed between larger, well-dated and regionally correlated paleoseismic sandy turbidites that extend along most of the Cascadia margin, northwestern United States. Investigation of the structure, distribution, and sedimentology of these thin mud-silt units supports the interpretation of these units as turbidites originating on the continental slope. Interpretation of mud turbidites is inhibited by bioturbation and lower response to analytical and imaging techniques; nevertheless most of the 23 interpreted beds exhibit most of the characteristics of coarser turbidites. These characteristics include sharp bases, fining upward sequences, darker color, increased gamma and CT density and magnetic susceptibility relative to the hemipelagic background, sparse microfossils, high lithic content, and evidence of transport from marine sources on the continental slope. New core data from sites south of Rogue Apron indicate that sandy and muddy turbidites may be correlated at least 150 km south to Trinidad Plunge Pool for the period ~ 4800 yr BP to present. Many of the mud turbidites initially described at Rogue Apron coarsen southward, becoming sandy turbidites. High-resolution Chirp seismic profiles reveal that turbidite stratigraphy along the base of the southern Cascadia continental slope is continuous, with little variation for at least 240 km along strike. The Chirp data show that turbidites along the Cascadia base of slope are ubiquitous, and likely not sourced solely from submarine canyon mouths, but may also have been delivered to the proximal abyssal plain as sheet flows from the open continental slope and coalescing local sources. Regional stratigraphy reveals that hemipelagic sedimentation rates and total Holocene turbidite thickness and mass are similar at widely separated sites, yet the total thickness of the Holocene section is greater by a factor of two in southern Cascadia. This difference is primarily due to the presence of the 21 mud and two additional sandy turbidites. We conclude that the Cascadia mud turbidites are ubiquitous along southern Cascadia only, with only one likely example of a correlated turbidite limited to the northern margin. Eight onshore sites including three marsh sites and five lakes include potential seismogenic correlatives of the southern Cascadia turbidites. In all, the onshore sites may have recorded > 80% of the events attributed to plate boundary earthquakes offshore during the period 0–6000 yr ago. Slope stability calculations suggest that earthquakes of Mw = 7.0 or greater should generate ground accelerations sufficient to destabilize open slopes and canyon heads with or without excess pore fluid pressure. Estimates of Mw for segmented ruptures are in the range of 7.4–8.7, exceeding the slope stability criteria for typical slopes by at least a factor of ~ four.
Citation: Goldfinger, C., Morey, A. E., Black, B., Beeson, J., Nelson, C. H., and Patton, J.: Spatially limited mud turbidites on the Cascadia margin: segmented earthquake ruptures?, Nat. Hazards Earth Syst. Sci., 13, 2109-2146, doi:10.5194/nhess-13-2109-2013, 2013.
Update on Sumatra Correlations
Here are two figures that go together. The first figure displays some cores in the region of the 2004 Sumatra Andaman subduction zone earthquake. The map shows their locations. The core figure shows the correlations I made using green lines to depict these correlations.
The second figure shows the technique I use to correlate the geophysical signature of these turbidites. I use three turbidite sequences T-4-5, T-5-7, and T-15-18 in 4, 4, and 3 cores. For each sequence, the upper panel shows the core imagery and MST data. The middle panel shows the MST data from each core grouped by geophysical parameter: Gamma density on the left, CT density in the middle (dark blue), and point magnetic susceptibility on the right (red). The upper two panels display all core data in the same vertical scale. The lower panel shows the MST data scaled (aka “flattened”) to stratigraphic horizons (e.g. the turbidites).
M 6.8 on the South Island of New Zealand
here is a big earthquake! M = 6.8, now a 6.5 depth = 10km pretty shallow (may change). it ruptured part of the Marlborough fault zone (part of the Alpine fault system).
the moment tensor fits the fault map, a right lateral strike slip earthquake on northeast striking fault (most likely).
looks like the eel river valley, but in New Zealand: USGS kml file
there was a smaller quake swarm just to the east in the last 2 weeks (they are in orange in my map). it caused landslides (lateral spreads i saw in some photos). this EQ may indeed be related, but i have no direct information about that (tho triggering that does happen proceeds in a short time following the trigger quake). ill need to look that last one up.
here is the usgs page:
http://comcat.cr.usgs.gov/earthquakes/eventpage/usb000j4iz#summary
here is an article on the damage:
http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=10913399
here is a map
here is a map with the USGS shakemap overlay:
here is a map with historic earthquakes plotted as grey circles (note epicenters near Christchurch on the lower part of the map):
here is a low angle oblique view, looking south-west along the axis of the south island. the Marlborough fault system forms the mountain ranges you are looking at (they are largely pointed at you). the main M=6.5 epicenter is the large orange dot above the red dot (“…just below the main port” in star wars). the Alpine fault is the red line off in the distance (though it is not placed well due to the scale of those data).
here is a map made by Mike Norton:
here is the usgs page on the tectonics of the region:
4.5 MB pdf