Page 2 - Interplay_1995

2 S. C/oetingh et al./ Tectonophysics 252 (1995) 1~5

tion of a number of research initiatives, such as the evolution. Delvaux et al. (this volume) demonstrate
lntegrated Basin Studies Project (Cloetingh et al., the importance of quantifying the connection be-
1995a), involving exchange of modelling concepts tween pre-rift evolution and the paleostress evolution
and data sets between industry and academia. of the Baikal region. Mindszenty et al. (this volume)
Regional studies carried out to test new models link in their paper the development of transient
have led to the decision to organize the Task Force regional unconformities to changing stress fields,
workshops at sites located in basins and to focus on presenting novel approaches to separate effects of
a particular aspect of basin formation. Benevento, tectonics and eustasy.
the site of the workshop well located within the
Southem Apennines forelandjfold-and-thrust belt in 2.2. Rheology and basin formation
the vicinity of the Tyrrhenian Sea, offered an out-
standing opportunity to study the interplay of exten- Rheology forms a controlling element in the basin
sion and compression. Well exposed sections and formation models (Vilotte et al., 1993; Quinlan et al.,
offshore data from detailed marine studies of the 1993; Bassi, 1995). The incorporation of a finite
Tyrrhenian Sea enable a careful examination of the strength of the lithosphere during extension in these
fine structure of the basin record (D' Argenio et al., models (Kooi et al., 1992; Spadini et al., 1995)
1993). In addition to its association with field expo- strongly affects predictions of rift shoulder develop-
sures, the meeting offered an excellent platform to ment and basin architecture. Spadini et al. (this
discuss recent research and new data from the Apen- volume) demonstrate the importance of a better un-
nines and Tyrrhenian Sea. derstanding of basin rheology for the stratigraphic
An important aspect of the Task Force meetings, development of the Tyrrhenian Sea. These forward
reflected also in the papers in this volume, is the modelling approaches can now be combined with
participation of PhD students and young researchers. backstacking of eroded sediments from rift shoul-
Further integration of different aspects of basin re- ders, constrained by fission track data and modelling
search will be useful both in a research career as (V an der Beek et al., 1994, 1995) to obtain quantita-
well as in future employment within the petroleum tive insights in the coupling between sediment
industry. sources and fills.
A better understanding of the rheological aspects
of extensional basin evolution is also an important
2. Themes of the Task Force and highlights of ingredient towards better models for basin inversion,
recent developments as demonstrated by modelling studies of Centrai
lberian basins (Van Wees and Stephenson, this vol-
2.1. Stresses and basin evolution ume) and the Polish Trough (Dadlez et al., this
volume).
On a basinwide scale, stresses are an important Pre-existing structures exert a key contro] on the
tectonic factor in the contro] on basin stratigraphy mode of extension (Buck, 1991; Bassi, 1995; Cloet-
and fluid flow (Van Balen and Cloetingh, 1993, ingh et al., 1995a, b). The paper by Mogensen (this
1995). As shown by Ziegler et al. (this volume), volume) demonstrates the structural relationships be-
changes in stress regime play a crucial role in the tween basin deformation and basin development
dynamics of large-scale basin deformation. The de- along the Danish segment of the Tomquist zone.
termination of stresses in basins through industry Causai relationships can also be explored on the
well breakouts (e.g., Muller et al., 1992) and mea- subbasin scale, where the role of faulting has been
surements in deep continental drill holes (Zoback et modelled by the application of, for example, flexural
al., 1993) will be further developed by the Task cantilever models (Kusznir et al., 1991). The inter-
Force (Zoback and Burke, 1993). Documenting spa- play of faulting and sedimentation in an extending
tial and temperai changes in paleostress fields in and deforming basin is discussed in the paper by
basins (e.g., Hippo1yte et al., 1993; Hibsch et al., this Grunalleite and Gabrielsen (this volume) on the More
volume) is vita] for a better understanding of basin Basin of offshore Norway.