TROPICS

Figure 13. A geologic map of Costa Rica and a schematic depiction of locations for various
sampling and mapping campaigns, and morphotectonic studies
4. Overview of the Research Plan
New observations are a key component of our research plan, and are vital for
testing the hypotheses set out in Section II. Key observables include: bulk
composition of the crust; crustal thickness; thickness of the lithosphere;
composition and physical state of the upper mantle; the history of magmatism,
unroofing and surface uplift.
Our research plan integrates geophysical, geochemical and geomorphological
methods relevant to each observable, and has major observational efforts in each
of these three areas:
1. Extensive sampling and analysis (geochemical, petrological, mineralogical)
of crustal rocks, and where available, lower crustal and mantle xenoliths;
2. A passive seismic array targeting the structure of poorly studied southern
and eastern Costa Rica;
3. Geomophological studies of landforms that constrain uplift history.
Knowledge of the bulk composition of the crust, and its geographic variation, is
key to defining the degree to which it has become continent-like. Seismic
C-20
TPI 6838742