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After five years of survey and the rescue excavation in 1989, large scale excavations started at Sagalassos from July 11th until August 22nd 1990. The work was directed by Professor Marc Waelkens (Dept. of Archaeology, Catholic University of Leuven) and by the Archaeological Museum of Burdur, represented by Ali Harmankaya, temporary director of the museum, who also represented the Turkish Antiquities Department. During the excavation the Council of Ministers granted a full scale excavation permit to Marc Waelkens. The team included 18 scientists and students from the Catholic University of Leuven, three from Britain and four from Turkey. Financial support came from the Research Council of the Catholic University of Leuven, from the Belgian Fund for Collective Fundamental Research, the Flemish Ministry of Education, the Ministry of the Flemish Community (Foreign Relations), the ASLK/CGER Bank, the Belgian tour operator ORION, and from the association “Friends of Sagalassos”. Thanks are due to the Anıtlar ve Müzeler Genel Müdürlüǧü and the Bakanlar Kurulu, who gave permission for the excavation, to the staff of the Emniyet Müdürlüǧü and the Archaeological Museum in Burdur, and to the Belediye officials and the inhabitants of Aǧlasun.

The lower Visean Belle Roche breccia (east Belgium) displays a number of features that indicate brecciation by evaporite dissolution collapse : the sharp lower contact of the breccia, the gradual transition into the overlying strata, the presence of semi-continuous beds within the breccia giving it a crude 'stratification', and the existence of several types of (calcite, dolomite and silica) evaporite pseudomorphs. Furthermore, the majority of the breccia fragments indicates hypersaline to lagoonal sedimentation conditions. Most of these fragments display an interlocking fabric. The interpretation is also supported by the existence of continuous evaporite beds replaced by carbonates (calcite and dolomite) both under-and overlying the breccia.The brecciation history is characterized by gradual subsidence. Multiple brecciation episodes are recognized, and are best seen in the lower breccia which underwent at least two major brecciation episodes. Here, brecciated and veined breccia fragments occur within a microsparite (neomorphosed mud) matrix. Brecciation of these strata was due to the dissolution of interlayered evaporites. The second brecciation event relates to infiltration of meteoric water and to the dissolution of the remaining evaporites. This infiltration was probably triggered by the orogenic event at the end of the Visean (Sudetic orogenic phase). The whole breccia was finally cemented by a blocky calcite.The different lithologies and cements were characterized by their trace element (Mg, Sr, Na, Fe, Mn, K), insoluble residue and organic matter content. Carbon/oxygen isotope data of the cements and replaced evaporite layers helped to place the multiple collapse episodes within a general diagenetic model. Solutionreprecipitation processes within the original aragonite-dominated mud fragments, as well as in the early diagenetic dolomite fragments, have been recognized. The geochemical data show that these transformation processes occurred in equilibrium with the same fluid. These processes may have occurred within a freshwater lens very early in the diagenetic evolution or under shallow burial conditions. Cementation of blocky calcite occurred in a meteoric realm under burial conditions. . 173-180.Ogy, 33,221-241.

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Upper Visean limestones in the Campine Basin of northern Belgium are intensively fractured. The largest and most common fractures are cemented by non‐ferroan, dull brown‐orange luminescent blocky calcite.First melting temperatures of fluid inclusions in these calcites are around ‐57°C, suggesting that precipitation of the cements occurred from NaCl‐CaCl2‐MgCl2 fluids. The final melting temperatures (Tmice) are between ‐5 and ‐33°C. The broad range in the Tmice data can be explained by the mixing of high salinity fluids with meteoric waters, but other hypotheses may also be valid. Homogenization temperatures from blocky calcite cements in the shelf limestones are interpreted to have formed between 45 and 75°C. In carbonates which were deposited close to and at the shelf margin, precipitation temperatures were possibly in the range 70‐85°C and 72‐93°C, respectively.On the shelf, the calcites have a δ18O around ‐9.3‰ PDB and they are interpreted to have grown in a fluid with a δ18O between −3.5 and +1.0‰ SMOW. At the shelf margin, blocky calcites (δ18O∼ ‐ 13.5‰ PDB) could have precipitated from a fluid with a δ18O betweenn ‐4.0 and ‐1.1‰ SMOW. The highest oxygen isotopic compositions are comparable to those of Late Carboniferous marine fluids (δ18O= ‐ 1‰ SMOW). The lowest values are more positive than a previously reported composition for Carboniferous meteoric waters (δ18O= ‐7‰ SMOW). Precipitation is likely to have occurred in marine‐derived fluids, which mixed with meteoric waters sourced from near the Brabant Massif. Fluids with a similar negative oxygen isotopic composition and high salinity are actually present in Palaeozoic formations. The higher temperature range in the limestones near the shelf margin is explained by the upward migration of fluids from the ‘basinal’ area along fractures and faults into the shelf.

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