The Bantimala Complex of South Sulawesi, Indonesia is an assemblage of northeastdipping tectonically stacked slices. The slices consist mainly of high pressure metamorphic rocks, radiolarian chert, breccia, sandstone and shale, and melange. In order to understand the tectonic evolution of the Bantimala Complex, we have investigated the lithology, age, stratigraphy, structure and relationships of the components. The K-Ar ages of high P-low T metamorphic rocks suggest that an oceanic plate subducted beneath the Sundaland continent during the Late Jurassic or earliest Cretaceous. The subduction ceased during the Albian, and the high pressure schists were exhumed and eroded at the surface before and during the deposition of middle Cretaceous radiolarian chert. The exhumation of the schists was related to the collision of microcontinents derived from Gondwanaland. The Jurassic shallow marine sedimentary rocks in the Bantimala Complex are possibly remnant fragments of the collided microcontinent. Tectonic stacking of the Bantimala Complex was caused by Neogene subduction and collision of another continental fragment further to the east.

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The Bantimala Complex of South Sulawesi consists mainly of mklange, chert, basalt, ultramafic rocks and high pressure type metamorphic rocks. Well-preserved radiolarians were extracted from 10 samples of chert, and K-Ar age dating was done for muscovite from five samples of schist of the Bantimala Complex. The radiolarian assemblage from chert is assigned middle Cretaceous (late Albian-early Cenomanian) age, while the K-Ar age data from schist range from 132 Ma to 114 Ma except for one sample with rare muscovite. The radiolarian chert is unconformably underlain by schist in the Bantimala Complex. The stratigraphic relationship and the time lag of these two kinds of age data from chert and underlying schist suggest short-time tectonic events immediately followed by a quick waning tectonism in this region during the Albian-Cenomanian transgression.

Rocks of the Lok Ulo Complex crop out over a small area in the vicinity of Karangsambung in central Java. They are part of a belt of Cretaceous accretionary-collision complexes that appear sporadically in an arc extending from Java to Kalimantan and Sulawesi. The complex consists of dismembered ophiolites, sedimentary rocks, and crystalline schists and gneisses occurring as tectonic slabs in a black-shale matrix tectonic mélange. High-pressure rocks such as eclogite, glaucophane rock and blueschist crop out in a thin zone between the low-grade schists and a serpentinite zone along the Muncar and Gua rivers. Some of the eclogite blocks contain tourmaline, which is restricted to the outer shells of-and veins in-such blocks.The early metamorphic stage (stage I) of the Lok Ulo eclogites comprises garnet (core) and omphacite + Ca-Na amphibole + phengite + rutile + epidote inclusions in the garnet core. Stage II is characterized by garnet (rims of porphyroblasts) + omphacite + rutile + phengite + Ca-Na amphibole. The matrix constituents, which are similar to those of stages I and II, are related to stage III (late or "peak" eclogitic stage). The blueschist overprint of the eclogites occurred during stage IV. The corresponding assemblage is Na amphibole + chlorite + albite + epidote + quartz + titanite + ilmenite. Subsequently, poikiloblastic tourmaline and apatite grew at the expense of chlorite, epidote, and other minerals in some eclogites (stage V).The P-T path of tourmaline-bearing eclogites is characterized by rising pressures at decreasing temperatures (stage I to stage III: P = 22.5 kbar and T = 365°C), whereas the normal eclogites show rising temperatures at increasing pressure (stage III: P = 20.5 kbar and T = 410°C). Thus, these eclogites were subducted to ~70 km depth at a geothermal gradient of ~6 C°/km. Stage IV is limited to the P-T range of 8-10 kbar and 350-400°C for both eclogite types. The different P-T paths (counterclockwise and clockwise) are explained by metamorphism within a subduction channel. The low geothermal gradient is probably due to a high rate of subduction of a cold oceanic plate.