Geodynamics and Neotectonic Forearc Deformation: Late Pliocene-Recent Basins, Hellenic Arc (Greece)

9815028 Kleinspehn弧前区域显示出广泛的运动学行为，包括弧前内部的变形。 在全球弧前构造中，平行弧拉张是最常见的内部应变形式，它能产生巨大的弧前快速隆升。 本研究的目的是建立俯冲带动力学和观察到的内部新构造应变的南部和东南部的希腊前弧（希腊）作为岩石圈收敛的功能的结晶度之间的关系。 通过检查年轻盆地沿弧前走向沿着记录的运动学，从会聚几乎正交的克里特岛向东到会聚矢量高度倾斜的Rhodos岛，将讨论关于驱动新构造弧前隆起机制的几个备选假设：（1）弧形平行伸展，（2）放射状伸展，（3）缩短，（4）扭压或扭张作用下的扭动构造。 结合构造制图/运动学分析、构造地层学和年龄关系沿着与弧前地球动力学的三维建模，将解决沿弧走向沿着的运动学变化，并增加收敛的一致性。 通过利用上新世晚期-现代盆地的充填物进行时间和古地理控制，并记录其同沉积期和沉积后变形以及邻近基底运动学，将出现弧前内部的新构造变形。 定量岩石圈斜向会聚响应的能力依赖于结合使用4 OAr/39 Ar地质年代学，磁性地层学和生物地层学的盆地的定年变形。 将研究限于最年轻的盆地限制了推断运动学的年龄，并将利用沉积盆地固有的垂直速度记录。 三维数值模型的结果将比较观察到的构造地层和defon-national模式链接岩石圈地球动力学观察到的应变和比较希腊系统的其他内部变形前弧全球。 拟议的研究将检查陆上构造地层学相当于海上序列很快将在海上钻井计划的一个腿的目标，并将补充目前计划在克里特岛ICDP项目，以评估覆盖板的前缘的力学行为。 由于这项研究涉及现代构造，因此与地震活动，地形变化和海洋海岸线迁移对古代和现代地中海文化的影响的考古学研究有关。 了解驱动这些弧前岛屿的新构造隆起的机制，可以更准确地评估这些有人居住的岛屿附近的地震危险性。

9815028Kleinspehn Fore-arc regions display a wide range of kinematic behaviors, including deformation internal to the fore-arc. Among fore-arcs globally, arc-parallel extension is the most commonly observed internal strain and it can produce substantial rapid fore-arc uplift. The goal of this study is to establish the relationship between subduction-zone dynamics and observed internal neotectonic strain of the southern and southeastern Hellenic fore-arc (Greece) as a function of the obliquity of lithospheric convergence. By examining the kinematics recorded by young basins along strike in the fore-arc going eastward from Crete, where convergence is nearly orthogonal, to the island of Rhodos where the convergence vector is highly oblique, several alternative hypotheses concerning the mechanisms driving neotectonic fore-arc uplift will be addressed: (1) arc-parallel extension, (2) radial extension, (3) shortening, or (4) wrench tectonics under transpression or transtension. Combined structural mapping/kinematic analyses, tectonostratigraphy, and age relations along with threedimensional modeling of the fore-arc geodynamics will address the changing kinematics along the strike of the arc with increasing obliquity of convergence. By using the fill of Late Pliocene-Recent basins for temporal and paleogeographic control and documenting its synand post-depositional deformation as well as adjacent basement kinematics, the neotectonic defon-nation internal to the fore-arc will emerge. The ability to quantify the lithospheric response to oblique convergence relies on dating deformation using combined 4OAr/39Ar geochronology, magnetostratigraphy and biostratigraphy of the basins. Limiting the study to the youngest basins restricts the age of the inferred kinematics and will capitalize on the vertical velocities inherently recorded by sedimentary basins. Three-dimensional numerical model results will be compared to the observed tectonostratigraphic and defon-national patterns to link lithospheric geodynamics to the observed strain and to compare the Hellenic system to other internally deforming fore-arcs globally. The proposed study will examine onshore tectonostratigraphy equivalent to offshore sequences soon to be targeted during a leg of the Offshore Drilling Program and would complement a currently planned ICDP project on Crete to evaluate the mechanical behavior of the leading edge of the overriding plate. Because this study addresses modem tectonics, it is relevant to archeological studies of the impact of seismicity, changing topography and migrating marine shorelines on ancient and modem Mediterranean cultures. Understanding the mechanisms driving neotectonic uplift of these fore-arc islands may enable more accurate evaluation of seismic hazards in the vicinity of these populated islands.