We look forward to seeing you in Washington at the AGU annual meeting

Date

 

Pegasus

 

Come to our booth #828 to see the new solution that will revolutionize portable monitoring campaigns

 

 

Customer Appreciation Event

 

Customer appreciation event

 

Poster Presentations 

A novel approach to generate research grade seismic catalog in real time; Machine learning application
Presenting author: Andrew Reynen

Day: Dec 10, 2018
Time: 8:00 AM - 12:20 PM
Section: Seismology, Poster Hall
Session: S11E Extracting Information from Geophysical and Geochemical Signals: Applying Machine Learning Through Data Science Challenges Posters

 

Abstract

 

When it comes to induced seismic risk management, accuracy, completeness and timeliness of generated event catalogs are critical to the utility and practicality of the seismicity attribute forecasts. Due to the vast amount of seismic data being collected, the construction of such catalogs can become time and labor intensive. Hence an accurate automated process is required to reduce the workload involved in catalog production.


Here we present a new technique, Feature Weighted Beamforming (FWB), which can be applied in near real-time to increase the accuracy of automatically generated catalogs, while maintaining the array sensitivity. In this approach, features are computed from 3-component seismograms utilizing spectral content, and common characteristic functions (STA/LTA, Kurtosis). Models relating the features to phase likelihood are formed using machine learning techniques. Likelihood values are referenced to P-S phase pairs which are stacked on a 4D grid representing event location and origin time. This method has been tested on multiple surface arrays and the results in comparison to conventional approaches, show a significant reduction in the distance between automatic solutions and their corresponding manually reviewed counterparts. The results from an induced seismic monitoring array over the Duvernay Formation in Western Canada (Duvernay Subscriber Array) are given here. As compared to standard STA/LTA picking with subsequent associations, FWB reduced the number of false positives by 75% as well as reducing the average difference in the event location between automatic and manually picked solutions by 82%.

 

Assessment of Earthquake Early Warning Methods for Complex Fault Ruptures
Presenting author: Emrah Yenier

Day: Dec 12, 2018
Time: 1:40 PM - 6:00 PM
Section: Seismology, Poster Hall
Session: S33E New Frontiers in Global Seismic Monitoring and Earthquake Research Posters

 

Abstract

 

Early warning systems should be able to automatically recognize seismic radiations and estimate shaking intensity of not-yet-arrived waves from early phase arrivals to maximize notification time. The accuracy of intensity estimates is as important as the warning lead time. However, timeliness and accuracy of issued warnings generally trade-off with each other due to time-dependent growth of seismic data. This trade-off adds further challenges to achieve reliable early warning systems, particularly for complex fault ruptures. In some cases, timeliness may be given the priority with an exchange of tolerable accuracy reduction for the initial warning. This tolerable level of accuracy reduction can differ from one recipient to another (e.g., public vs. critical infrastructure).

 

In this study, we examine currently used early warning approaches to identify their strengths and limitations from a perspective of different recipients, with focus on complex fault ruptures. The evolutionary accuracies of estimated source parameters and shaking intensities are assessed based on pseudo real-time data playbacks. We explore potential improvements in conventional early warning approaches by integration of ground-motion based methods.
 

 

A Direct Bury Deployment in Alaska of A New Low Noise Broadband
Presenting author: Tim Parker

Day: Dec 13, 2018
Time: 1:40 PM - 6:00 PM
Section: Seismology, Poster Hall
Session: S43E: Seismology Contributions: Advances in Instrumentation and Installation I Posters 

 

Abstract

 

The Nanometrics Trillium Horizon is a new and smaller low-noise broadband sensor purpose-built for both dry vault and direct bury installations in wet environmental conditions.  We installed a Horizon near an Alaska Earthquake Center station that was adopted by the Earthscope Transportable Array in 2014 with the installation of a 100-inch cased borehole. The site is on a ridge above the northern town of Nenana where AC power and telemetry are available. The direct bury sensor installation technique, which we used for the Horizon, is a method of installing a sensor by simply digging a hole and then ensuring adequate coupling by compacting the soil, sand or crushed rock around the sensor and having enough thermal mass to limit the diurnal temperature changes to the sensor.  The site NEA2 was chosen as a reasonable representative of the station noise performance of the regional Transportable Array stations. NEA2 has good performance metrics for comparison, and it has convenient access by road from Fairbanks.  We hope to give an early performance report using IRIS DMC type standard station metrics.

 

Qualification of Nanometrics Trillium 120QA Seismometers and Centaur CTR4-3A for Use in the International Monitoring System
Presenting author: Nicholas Pelyk

Day: Dec 14, 2018
Time: 1:40 PM - 6:00 PM
Section: Seismology, Poster Hall
Session: S53E Recent Progress in Nuclear Test Monitoring Capability Posters

 

Abstract

 

As part of Natural Resources Canada’s (NRCan) program of modernizing its seismic network, it is upgrading the instrumentation at stations that it operates in support of the International Monitoring System (IMS) of the Comprehensive Test Ban Treaty Organization (CTBTO). NRCan, through a competitive process, has selected Nanometrics Trillium 120QA seismometers, Centaur digitizers, and Titan accelerometers for both its national network and the IMS sites it supports. In addition, to achieving high reliability, data quality, and availability, a critical requirement is that the equipment meets IMS specifications.


NRCAN worked closely with Nanometrics to develop the new Authenticating Centaur datalogger that has built-in DSA and ECDSA data authentication, CD1.1 streaming, precision calibration signal generation, tamper detection, microbarometer and digital weather station support, and PTP/NTP network timing. The three or six channel Authenticating Centaur is fully self-contained so no external auxiliary boxes or computers are needed. Sandia National Labs tested the Centaur under NRCAN and CTBTO supervision to ensure CTBTO requirements are fully met and can be operationally deployed in the IMS. NRCan has been testing the instrumentation at three IMS locations to ensure compliance with specifications and consistency of data.