Age and Structure of a Fragment of the Early Cambrian Ophiolite Sequence (North Balkhash Zone, Central Kazakhstan)

A fragment of the ophiolite sequence composed of dunites, wherlites, pyroxenites, gabbro, gabbro-dolerites, and plagiogranites was described within the structure of the North Balkhash Zone of Paleozoides of Central Kazakhstan. This fragment represents a large block enclosed in the serpentinite mélange (Tesiktas massif). The Early Cambrian date ( 206 Pb/ 238 U; 531 ± 1 Ma) was obtained for the first time for plagiogranites of this massif. The age estimate is thought to indicate the termination time of the formation of the plutonic part of the ophiolite sequence.