Preface: clay mineral diagenesis and very low-grade metamorphic processes. Proceedings of the 2011 Frey–Kübler symposium
Swiss J Geosci
Preface: clay mineral diagenesis and very low-grade metamorphic processes. Proceedings of the 2011 Frey-Ku bler symposium
Rafael Ferreiro Mahlmann 0 1 2 3 4
Fernando Nieto 0 1 2 3 4
O mer Bozkaya 0 1 2 3 4
Sebastien Potel 0 1 2 3 4
Asuman Gu nal Tu rkmenoglu 0 1 2 3 4
0 O . Bozkaya Department of Geological Engineering, Cumhuriyet Technical University , 58140 Sivas , Turkey
1 F. Nieto Departamento de Mineralog a y Petrolog a and IACT, Universidad de Granada, CSIC , Av. Fuentenueva, 18002 Granada , Spain
2 R. Ferreiro Ma hlmann (&) Technical and Low Temperature Petrology, Institut fu r Angewandte Geowissenschaften, Technische Universita t Darmstadt , Schnittspahnstrae 9, 64287 Darmstadt , Germany
3 A. G. Tu rkmenog lu Turkish National Committee on Clay Science, Department of Geological Engineering, Middle East Technical University , 06531 Ankara , Turkey
4 S. Potel Institut Polytechnique LaSalle Beauvais , Equipe B2R, 19 rue Pierre Waguet, BP 30313, 60026 Beauvais Cedex , France
(i) Geologists who wanted to use low-grade metamorphic petrologic, geochemical, clay mineralogical, isotopic and coal petrographic methods for their specific studies (e.g. in sedimentary geology, basin analysis, hydrocarbon geology, and regional metamorphic geology), (ii) Research scientists interested in methodical and process aspects of diagenesis and low-grade metamorphism, and (iii) Structural geologists with specialization in orogenic research.
1 Introduction
In 2002, after the death of Prof. Bernard Kubler (Univ.
Neuchatel) and Prof. Martin Frey (Univ. Basel), Schmidt
and Ferreiro Mahlmann published a special issue on
Diagenesis and Low-Grade Metamorphism in the Swiss
Bulletin of Mineralogy and Petrology. Most contributions
had been presented during the Symposium on Diagenesis
and Low-Grade Metamorphism at the EUG meeting 2001
in Strasbourg, France, and had been dedicated to the two
most important researchers in that field. The underlying
philosophy of the Diagenesis and Low-Grade
Metamorphism issue, was to provide a compilation of the state of
the art in very low-grade metamorphic (VLGM) and low
temperature petrologic research to:
Frey had strong interest in and have strongly influenced
those specific fields. For this reason, two topics were
selected for the FreyKubler Symposium:
1. Elucidating geothermal evolutions of basins and orogenic wedges using clay mineral indices (regional case studies, tectono-metamorphic studies and metamorphic mapping), and
2. New advances in palaeo-geothermometry: comparing
clay mineral indices with other methods (theoretical
approaches, new methods and improvements in
methodology and calibration methods to determine grade of
diagenesis and metamorphism).
It is a pleasure to realize that nearly all contributors to
the FreyKubler symposium at EUROCLAY in Antalya
2011 have submitted their presentation for publication in
this issue.
2 Content of the issue
The issue starts with a review study by the four chairman of
the symposium together with B. S egvic and R. Le Bayon
(Ferreiro Mahlmann et al.), which gives a historical view of
the pioneer work of Martin Frey and Bernard Kubler and
the evolution of very low-grade studies in the last five
decades. This review covers their research in the Alps,
stressing the Kubler-Index (KI) versus vitrinite reflectance
(VR) and bituminite reflectance (BR) correlation. We
discuss also the progress in understanding the physical
meaning of the KI since the studies of Merriman et al.
(1990); S rodon et al. (1992); Nieto and Sanchez-Navas
(1994) and A rkai et al. (1996).
In comparison with KI, VR and BR data give different
regressions and slope trends depending on the geodynamic
conditions. Finally a critical discussion of the
geo-thermometric use of KI and VR data (including Raman studies)
is presented. For comparison of VR and BR with KI data, a
unified and homogeneous data set of values is necessary.
The study refers to nearly 5,000 values compiled and
correlated with the help of an inter-laboratory calibration
study (Ferreiro Mahlmann and Frey). At the same time the
study is a late result of the data compilation for the
metamorphic maps of the Alps under the leadership of Frey
et al. (1999) and Oberhansli et al. (2004). Problems to
include all published data from the Alps are due to different
preparation and measurement techniques. It is shown in the
review that standardisation and calibration of methods used
to determine grade of diagenesis to incipient
metamorphism are a fundamental pre-condition to successfully
draw VLGM maps (Frey and Ferreiro Mahlmann 1999)
and to reconstruct paleo-geothermal conditions and
geodynamic settings.
The following contributions are arranged according to
the two topics of the FreyKubler symposium starting
with two studies showing the methodical progress to
determine grade of diagenesis to low-grade metamorphism
and methods to calibrate the clay indices (Ferreiro
Mahlmann and Frey; Le Bayon). The first study
(...truncated)