When Did the Western Anatolian Grabens Begin to Develop?
When Did the Western Anatolian Grabens Begin to Develop?
复制标题
西安纳托利亚地堑何时开始开发？
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
A. Elmas
中科院分区：
文献类型：
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作者：
Y. Yılmaz;Ş. Genç;F. Gürer;M. Bozcu;Kamil Yılmaz;Z. Karacık;Ş. Altunkaynak;A. Elmas
为了解决关于西部安纳托利亚地堑系形成时间和机制的长期争论，在安纳托利亚西部填图项目中收集了新的资料，这些资料表明，最初南北走向的地堑盆地形成于早中新世时期的东西向伸展体制下。与大约南北走向的斜滑断层相关的伸展开口为钙碱性混合岩浆到达地表提供了通道。中新世晚期开始了南北向的伸展体制。在此期间，形成了一个主要的断裂断层。下部板块的一部分后来在博兹达费什、霍斯特隆起并出露，上部板块之上发育了大致南北向的交叉地堑。沿着这些断裂系统，碱性玄武岩熔岩被挤出。在晚中新世末或上新世早期，南北向伸展中断，表现为在新近纪岩石（包括上中新世-下上新世地层）上形成区域性水平侵蚀面。这种侵蚀几乎消除了以前形成的地形不规则，包括BozdaExpense海拔。后来，侵蚀面被破坏，控制中新统下-上统岩石发育的构造被恢复的南北向伸展形成的大致东西向正断层切割。这导致了现今东西向地堑在上新世-第四纪时期的发展。
Abstract To solve a long-lasting controversy on the timing and mechanism of generation of the western Anatolian graben system, new data have been collected from a mapping project in western Anatolia, which reveal that initially north-south trending graben basins were formed under an east-west extensional regime during Early Miocene times. The extensional openings associated with approximately north-south trending oblique slip faults provided access for calc-alkaline, hybrid magmas to reach the surface. A north-south extensional regime began during Late Miocene time. During this period a major breakaway fault was formed. Part of the lower plate was uplifted and cropped out later in the Bozdağ, Horst, and above the upper plate approximately north-south trending cross-grabens were developed. Along these fault systems, alkaline basalt lavas were extruded. The north-south extension was interrupted at the end of Late Miocene or Early Pliocene times, as evidenced by a regional horizontal erosional surface which developed across Neogene rocks, including Upper Miocene-Lower Pliocene strata. This erosion nearly obliterated the previously formed topographic irregularities, including the Bozdağ elevation. Later, the erosional surface was disrupted and the structures which controlled development of the Lower-Upper Miocene rocks were cut by approximately east-west trending normal faults formed by rejuvenated north-south extension. This has led to development of the present-day east-west trending grabens during Plio-Quaternary time.