Geochronology and Geochemistry of the Karadaban Bimodal Volcanic Rocks in the Altyn Area, Xinjiang: Implications for the Tectonic Evolution of the Altyn Ocean

Table 4

Rb-Sr and Sm-Nd isotopic compositions for the Early Cambrian bimodal volcanic rock in the North Altyn Tagh tectonic belt.

Sample	Rock	Age (Ma)				2σ				2σ		(Ga)
KB-26	Rhyolite	512	1.072	0.71677	0.70895	3	0.1225	0.51207	0.51166	2	-6.3	1.81
KB-33	Rhyolite	512	0.1004	0.71380	0.71307	3	0.1260	0.51217	0.51175	2	-4.5	1.70
KB-46	Rhyolite	512	0.9701	0.71785	0.71077	3	0.1362	0.51231	0.51185	2	-2.5	1.66
KB-76	Rhyolite	512	3.2086	0.73287	0.70946	3	0.1276	0.51223	0.51180	1	-3.5	1.63
KB-132	Rhyolite	512	0.0103	0.71140	0.71133	2	0.1440	0.51226	0.51178	1	-4.0	1.95
KB-19	Basalt	512	0.0717	0.70656	0.70604	2	0.1806	0.51277	0.51217	4	3.6	1.75
KB-23	Basalt	512	0.0532	0.70811	0.70772	6	0.1698	0.51269	0.51212	6	2.8	1.59
KB-70	Basalt	512	0.0645	0.70864	0.70817	3	0.1764	0.51271	0.51212	3	2.7	1.79