For the determination of the exact location and drilling geometry of the ICDP expedition 5071 DIVE (Drilling the Ivrea-Verbano zonE) phase 1 boreholes, we have carried out a series of active seismic experiments to image the subsurface at high resolution (Greenwood et al., 2024). The two drilling sites of DIVE phase 1 are located in the Ossola valley (Figure 1) in the Central part of the Ivrea-Verbano zone, one in Megolo di Mezzo (5071_1_A: IGSN ICDP5071EH10001, Münthener, 2024a) and the other near Ornavasso (5071_1_B: IGSN ICDP5071EH30001, Münthener, 2024a). A total of 4 seismic reflection surveys, one in Megolo, two in Ornavasso (Ornavasso primary and Or-navasso secondary), and a transect crossing from Premosello-Chiovenda south towards Megolo, make up the MicrO-SEIZE (MOS) data base.
The MOS surveys were conducted over a period of 12 days mid to late June 2019, utilizing a 26,000 lb (12,247 kg) EnviroVibe2™ vibrator source. Survey planning utilised existing roads, pathways, and open grass fields to cover as much area as possible around the borehole sites, to reduce the envi-ronmental impact on cultivation, and to ease operation logistics. A full description of the data can be found in Greenwood et al. (2024) and the data description file accessible via the data download link.
The data set was acquired in the framework of the CRC 1211 “Earth – Evolution at the dry limit” which aims to study continuous longterm (Quaternary-Miocene) paleoclimatic/environmental records from the hyperarid core of the Atacama desert / N Chile covering the last up to 10 Ma. As part of this project, three clay pans were investigated in the Coastal Cordillera (Huara 20° 4'32.75"S; 69°55'1.46"W; PAG: 21°32'27.39"S; 69°54'47.21"W; Paranal 24°29'20.53"S; 70° 8'54.63"W). The clay pans are located along a latitudinal transect across the hyperarid core of the Atacama from 20° S to 24.5° S. The seismic survey comprised a couple of crossing 2D high-resolution seismic lines per each of the clay pans, acquired with vertical component geophones, Geode recorders and a PEG-40 accelerated weight drop as source.