Recent News

PASSCAL provides open-source software, PASSOFT, for downloading seismic data from data recorders, for quality assessment, and for conversion to other data formats for analysis and archiving at the IRIS Data Management Center. The latest version of PASSOFT is now available for general use. It is Python 3 compatible, and can be downloaded here.

The 2020 Polar Technology Conference is planned for 10–12 March 2020 in Boulder, Colorado. This activity is a cooperative effort among the National Science Foundation’s Office of Polar Programs, the Arctic Research Consortium of the United States, and the polar research community.

The IRIS Education and Public Outreach program acquired a Sensors and Software Noggin GPR System with SmartCart configuration to enhance the IRIS PASSCAL equipment pool (see image at left). The system has onboard GPS, data acquisition programming, and preliminary data interpretation capabilities. The system has both line-scan or grid-scan data collection modes. The onboard software allows for quick survey setup, on-the-go viewing of the waveforms collected, and initial waveform depth estimates. Processed onboard data can be visualized as depth versus position along a line, or as a slice view of grid data. The PASSCAL Instrument Center offers additional software for more in-depth post acquisition processing and interpretation of the data.

Magnetotelluric (MT) methods are used to produce conductivity models of the crust and upper mantle through the recording of geoelectric and geomagnetic field variations at the Earth's surface. Depending on the period of the recordings, these methods can provide results from a few hundred meters depth (short period) to 30 km or deeper (long period). Conductivity is a physical property, which is complementary to seismic velocity, and which is very sensitive to the presence of fluids. When seismic and MT data sets are measured together, the additional data can dramatically improve determinations of the structure of the crust and mantle.  

Late 2018 PASSCAL learned of a GPS week rollover event that can affect data logger performance and timing. PASSCAL has acquired a GNSS signal generator that can emulate GPS satellite signals. This satellite emulator allows us to test PASSCAL equipment that relies on GPS timing and to determine how equipment will handle the GPS rollover event. To date, we have determined that some models of GPS engines are affected by the rollover. How the rollover errors manifest is dependent on the data logger’s model and firmware version of the GPS engine.

PASSCAL is pleased to announce the release of Nexus, a simple tool for creating SEED meta-data.

Nexus is a software tool with a graphical interface that allows users to quickly and easily create and modify SEED meta-data. It outputs StationXML, the recently adopted replacement format for Dataless SEED. Nexus greatly simplifies preparing data for archival at the DMC. 

As a response to the seismological community's desire to deploy a larger number of 3-component nodal seismic systems, the IRIS PASSCAL standing committee has guided IRIS management to procure more nodes for the PASSCAL pool. IRIS already has 73 Magseis Fairfield ZLAND 3-component 5Hz nodes in the pool and these have been subscribed for more than 2 years out. We have now begun the procurement of another 460 Magseis Fairfield nodes for general PASSCAL pool use. We expect to receive these new nodes in the fall of 2018. The new nodes should be ready for general pool usage starting in February, 2019 after evaluation and acceptance is complete (bringing the general node pool to 533 units). Please feel free to include the new nodes in instrument requests for experiments with start dates after February 2019.

IRIS/PASSCAL has updated our Data Policy. The new Policy, which was published on November 1, 2017,  can be perused here. It details the archiving requirements for data collected with IRIS PASSCAL equipment through the PASSCAL Instrument Center (PIC)