Sand on Salt - dune subsidence into a mobile substrate (PDMS)

This collection contains time-lapse photographs from experiments conducted by A. Piliouras and W. Kim, the results of which are published in Piliouras et al., (2014) in Lithosphere: http://dx.doi.org/10.1130/L323.1. More detailed methodologies can be found in the manuscript.

Seismic data from the Gulf of Mexico showed evidence of large lenticular sand bodies (linear dunes) partially subsided into the underlying Louann salt. The dunes were preserved after a marine transgression, and they had variable preserved topographies. We performed experiments to determine what controlled dune subsidence rates and the amount of subsidence, such that we might produce variable subsided dune topographies. The dune here is intended to be a cross section through a linear dune, so it is essentially a triangular pile of sand (silica) deposited relatively instantaneously on top of PDMS (polydimethylsiloxane), which we use as a proxy for salt (see references within Piliouras et al., (2014)). Run 1 has a sand to salt thickness ratio of 1 (sand thickness = salt thickness = 14.5 cm), while Run 2 has a ratio of 0.5 (sand thickness = 7.5 cm, salt thickness = 14.5 cm). Here we supply the original time lapse images and corresponding movies, as well as images corrected for camera lens distortion. Run 1 time lapse photos were every 5 minutes, and Run 2 time lapse photos were every 3 minutes. The lens corrected photos have 1 pixel = 1 mm. Flume dimensions can be found in the manuscript listed above to resize and/or process the raw photos.

本数据集包含A. Piliouras与W. Kim开展的实验延时摄影照片，相关实验成果已发表于Piliouras等人2014年刊载于《Lithosphere》（岩石圈）的论文，链接为http://dx.doi.org/10.1130/L323.1。更详尽的实验方法可参阅该手稿。
墨西哥湾的地震数据显示存在大型透镜状砂体（线性沙丘），此类砂体部分沉降至下覆卢安盐层（Louann salt）中。海侵作用后这些沙丘得以保存，且其保存的地形具有多样性。我们开展实验以明确控制沙丘沉降速率与沉降量的关键因素，进而实现可变的沉降后沙丘地形。本研究中的沙丘指代线性沙丘的横截面，本质上为瞬时沉积在聚二甲基硅氧烷（polydimethylsiloxane）基底之上的三角状二氧化硅砂堆，我们以PDMS作为盐岩的替代介质（详见Piliouras等人2014年论文中的参考文献）。
实验1的砂层与盐层厚度比为1（砂层厚度=盐层厚度=14.5 cm），实验2的该比值为0.5（砂层厚度=7.5 cm，盐层厚度=14.5 cm）。本数据集提供原始延时摄影图像及对应视频，同时包含经相机镜头畸变校正后的图像。实验1的延时摄影照片拍摄间隔为5分钟，实验2的拍摄间隔为3分钟。经镜头校正后的图像分辨率为1像素对应1毫米。水槽尺寸可参阅上述手稿，以用于原始照片的尺寸校正与/或后期处理。