P. Schmoldt, PhD - MTNet - DIAS

9.1. Profile location
Data collection and processing
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In October and November 2007 magnetotelluric (MT) data are acquired along an approximately
400 km long, north-south oriented profile from a region around 100 km east of
Madrid to the city of Almeria near the Mediterranean Sea, crossing the Tajo Basin and
the Betic Cordillera (cf. Figs. 7.1 and 9.1). North-south orientation of the profile is chosen
in order to intersect the main geological feature, i.e. the Betic Cordillera, as close
to perpendicular as possible and to allow for continuation of the profile on the southern
side of the Mediterranean Sea. Subsequent fieldwork campaigns in Morocco are executed
as part of the PICASSO Phase II and TopoMed projects, as well as a marine survey in
the Alboran Domain by the AMELIE project. As well as being informative in their own
right about the nature of the lithosphere of the central Iberian Peninsula, data from the PI-
CASSO Phase I project can support investigations of these subsequent projects regarding
nature of the putative anomaly beneath the Alboran Domain [e.g. Platt and Vissers, 1989;
Seber et al., 1996; Calvert et al., 2000] and the complex plate tectonic processes involved
in the continental collision between Africa and Europe.
The location of the PICASSO Phase I profile is chosen to avoid sources of electromagnetic
(EM) noise, like highly populated areas and the electric train network, as much as
possible. Along the profile, data are successfully recorded at 20 locations using Phoenix
Geophysics broadband MTU-5 stations and Lviv long-period LEMI-417 stations, with a
station spacing close to 20 km where possible. A description of recording systems and
their installation in the field is given in Chapter 6. Additional broadband recordings are
conducted at four locations along certain parts of the profile, reducing the station spacing
to 10 km in order to increase the resolution in these regions. A complete list of all stations
installed during the PICASSO Phase I fieldwork campaign together with their location
and duration of recording is given in Table 9.1 and in the timeline plot (Fig. 9.2). The
profile can be divided into sections according to the different geological setting (Figs. 7.1,
9.1) as summarised in Table 9.2; see Section 7 for details about local geological settings.
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