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报道了粤北梅州地区霞岚杂岩的SHRIMP锆石U-Pb年龄,花岗岩(196±2)Ma,辉长岩(195±1)Ma,为中国东南部缺少200~180Ma期间的岩浆岩报道增添了新资料,又表明了滨太平洋构造域至少在195Ma左右已经开始作用于中国东南部.野外揭露的新鲜露头上,辉长岩与花岗岩之间有岩浆部分混合作用现象.辉长岩局部发育20~30cm的细粒边,从辉长岩往花岗岩方向逐渐变细;花岗岩中发育大量暗色细粒-微粒闪长质岩浆包体,形态多样、大小不一,边部有暗色矿物集中现象,部分界线呈截然、模糊或过渡关系;包体中出现针状磷灰石;辉长岩类与花岗质岩石的稀土配分模式基本一致,其微量元素特征也具有明显的一致性;二者年龄十分接近,且基性岩略晚于花岗岩形成.这些特征均表明,早侏罗世基性岩浆注入引起了深部陆壳物质的熔融,并形成了酸性岩浆,然后二者发生混合产生了霞岚杂岩.
The SHRIMP zircon U-Pb age, granite (196 ± 2) Ma and gabbro (195 ± 1) Ma are reported for the Xialan complex in Meizhou, northern Guangdong, and are reported as magmatic rocks in the southeastern part of China for a period of 200-180 Ma Added new data, and showed that the Pacific Ocean tectonic domain has started to act on southeastern China at least about 195 Ma.On the exposed fresh outcrops, there is a magmatic mixing phenomenon between gabbros and granites.Development of gabbro Fine granule edge of 20 ~ 30cm, from gabbro to granite direction tapering; granite in the development of a large number of dark-colored fine-particle diorite magma inclusions, the shape and diversity, the size of the edge of dark mineral concentration, Part of the boundary showed a sharp, fuzzy or transitional relationship; acicular apatite appeared in the inclusions; the gabbros of gabbro and granite were basically the same, and their trace element characteristics were also obviously consistent; both age Are very close and the basic rocks are slightly later than the granite.These characteristics indicate that the Early Jurassic basic magmatic injection caused the melting of the deep continental crustal material and formed the acidic magma which then mixed to produce Xialan Complex .