Model SOILSPY - Multichannel Seismograph
Bringing the past of multichannel seismographs to a new life. SOILSPY is the MoHo’s multichannel digital system for active and passive seismic surveys. A number of unique features make it a very special seismograph. The signal is amplified and digitized where it is produced and not at the end of long cables: this ensures better recording quality and, allied to a lightweight system, forms a novel approach appreciated by geophysicists. SOILSPY does not require external batteries and can record the signals with no time limits, which extends its applications well beyond seismic methods.
SOILSPY is a multichannel seismograph. The seismic signal is amplified and digitized directly at the geophone output and sent to the laptop PC along a digital cable. This ensures higher signal quality (no cross-talk among cables, no noise coupled along the cables) and an unprecedented light weight.
SOILSPY is powered directly from the USB port of any portable or pocket PC and does not require any external battery.
A further exclusive feature is the unlimited recording duration, which makes the system particularly suited for passive seismic surveys and long term monitoring.
P- and S- wave methods
Seismic refraction and reflection methods, including tomographic approaches.
Passive (ReMiTM, SPAC, ESAC, SSAP) and active methods (SASW, MASW, SPAC, FTAN) based on the dispersion of surface waves.
Downhole and cross-hole methods (borehole geophone not provided)
- Better Recording Quality. The signal does not degrade along the cable, signal-to-noise ratio is higher than any corresponding analog system, no cross-talk along the cable, precise synchronization of the channels
- No External Battery. The system is powered directly by the USB port of any portable or pocket PC
- Extreme Lightness. 200 g per module + 5 m cable, i.e. 3.2 kg for a 16 channel system (geophones excluded)
- Unlimited Recording Duration. No compromise among sampling rate, number of active channels and recording length. Record length is limited by the PC storage capacity only
- Radio Triggering Device. No need for a separate trigger cable to perform seismic refraction/reflection surveys
- Stacking / Phase Inversion / Averaging unique routine for the revision of stacks and operations on them
- Integrated Internal Test to verify the functionality of each channel
- Modularity. Several SoilSpy Rosina systems can be linked to form a unique deployment
- POWER SUPPLY: 3.3 V (from 5 V of the PC USB interface)
- POWER CONSUMPTION: 0.55 W (12 channels @128 Hz)
- BATTERY: non existent. Powered from PC/pocket PC
- SAMPLING: 32 kHz per channel in continuous mode
- A/D CONVERSION: 24 bit equivalent
- OUTPUT FREQUENCY: (fs) 256, 512, 1024, 2048, 4096, 8192, 16384, 32768 Hz
- RECORDING LENGTH: continuous - no limits for fs < 2048 Hz stacking mode - selectable, available at all sampling rates
- DYNAMIC RANGE 142 dB, selectable among different levels
- BAND: DC - 360 Hz
- COMMON MODE: REJ. > 90 dB
- CROSS-TALK: non existent (digital transmission among channels)
- MAX CHANNEL NO. 255 (nominal) TRIGGER: each channel can be set as trigger and acquire at the same time. No need for a
- separate trigger cable Classical trigger from the interface and radio trigger
- PRE-TRIGGER: several options (up to 1 s)
- VISUALIZATION: allows for continuous visualization in real time
- STACKING / PHASE INVERSION /AVERAGING: dedicated software routine with unique features
SoilSpy Rosina can perform:
- P and S wave refraction surveys
- reflection surveys
- 1D (e.g., ReMiTM) and 2D (e.g., SPAC, ESAC) passive seismics
- surface wave based active seismics (e.g., SASW, MASW, FTAN)
- down-hole and cross-hole surveys
- long monitorings
Several kinds of passive sensors can be connected to the system.
SoilSpy Rosina software allows to set the acquisition parameters, to view the recordings and pre-process data.
Two acquisition modes are available: 1) continuous (Figure 1) and 2) fixed duration after trigger (Figure2). The software allows to review all the acquired time-segments, to discard the noisy ones, to stack or subtract them (phase inversion routine for S-wave refraction surveys), to pick the various phases. Several options are available for manual and automatic gain setting, trigger setting and to check the system functioning.
The Grilla software stores in a database the recordings acquired by SoilSpy Rosina, allows to determine the surface wave phase velocity spectra (ReMiTM, MASW, ESAC, etc.) and to model surface wave (Rayleigh and Love) phase velocity dispersion curves in the fundamental and higher modes.
Grilla allows to plot virtually infinite velocity spectra from recordings acquired by SoilSpy Rosina in continuous mode and allows joint fitting of H/V and dispersion curves (Figure 2).
Grilla compiles an automatic report in Microsoft Word format, including tables and figures.