Unravelling the Gordian Knot: Integrating Advanced Portable Technologies into the Analysis of Rock-Art Superimposition

数千年来，在地球仪上，人类在洞穴和其他石头表面上绘制图像。一些绘画的地点后来被人们重新访问，他们在旧的上面添加了新的绘画。这些地点可以是非常丰富多彩的，复杂的绘画组合，一个放在另一个上面，以至于很难辨别很长一段时间内的绘画顺序。虽然考古学家已经开发了许多复杂的理论来解释这些绘画，并且已经脱落的绘画碎片可能会在实验室中进行分析，但直到最近，当绘画留在岩石表面时，使用强大的科学设备来分析绘画一直非常困难。然而，技术的进步已经产生了小型的可移动设备，现在可以进行详细的现场分析，而不会损害绘画。这些非破坏性的便携式技术可以扫描洞穴，岩石表面和绘画三维;可以使用X射线技术来确定用于制作绘画颜料的化学元素;激光仪器来识别绘画的有机成分;并可以使用便携式数字摄影来揭示隐藏的层通常人眼几乎察觉不到。解开戈尔迪之结项目将应用所有这些方法来分析壮观和丰富多彩的绘画在网站所谓的普莱托，发现在加州，美国。Pleito是世界上最复杂的彩绘遗址之一。它有数百幅色彩各异的个人画作，包括不同色调的红、黑、白色、黄、橙子、绿色和蓝色。这是北美任何已知遗址中最广泛的调色板，重要的是，它有多个面板，其中绘画被放置在早期的面板上。这种被称为叠加的过度绘画，对岩石艺术研究人员来说是最大的挑战，因为他们试图理解在风景中发现的绘画艺术。尽管如此复杂的绘画具有挑战性，但它们为能够解开序列的考古学家提供了了解绘画发展的最大机会。在Pleito遗址内，研究人员称之为“Gordian Knot”的面板是那里发现的最精致的面板，使其成为世界上任何地方发现的最复杂的史前面板之一。这个项目的名字来自这个面板，因此Pleito及其以各种颜色执行的复杂序列是解开绘画事件历史的理想案例。所采用的方法将整合一系列便携式技术，包括便携式X射线荧光，便携式拉曼光谱，高光反射变换，dStretch数字摄影和便携式数字激光扫描，以解开绘画序列，构成世界上最复杂的网站之一。这些技术将有助于解决有关颜料使用传统的问题，并深入了解艺术在土著社会中的作用。该项目包括一个最先进的网站与三维娱乐将被安置在加州州立大学，海峡群岛，提供替代网站访问作为一种手段，体验该网站没有损坏古代绘画的风险。此外，一项新的条件评估将比较该网站的退化与2003年的基线报告，看看有多少绘画最近被侵蚀了：最后，一系列实验将不同的颜料与不同类型的粘合剂结合起来，将为我们提供材料，以测试实验室和便携式设备在创建光谱数据库：这将为我们提供一系列不同的化学读数，以与实际绘画进行比较，并允许世界各地的研究人员将他们的发现结果与戈尔迪结光谱数据库进行比较

For thousands of years and across the globe, humans have painted images in caves and on other stone surfaces. Some painted sites were later revisited by people who added new paintings on top of the older. Such sites can be very colourful, complex assemblages of paintings placed one on top the other, so much so that it can be very difficult to discern the sequence of painting over very long periods of time. While archaeologists have developed many sophisticated theories to interpret these paintings, and pieces of the paintings that have fallen off may be recovered to analyze in a laboratory, until recently it has been very difficult to analyse the paintings using powerful scientific equipment while the paintings remain on the rock surface. However, technolgoical advances have produced small transportable devices which now allow for detailed on site analyses that do not harm the paintings. These non-destructive portable technologies can scan the cave, rock-surface, and paintings in 3-Dimensions; can use X-ray technology to determine the chemical elements used to make the pigment that makes the painting; laser instruments to identify organic components of the paintings; and can use portable digital photography to reveal hidden layers normally barely perceptible to the human eye. Unravelling the Gordian Knot Project will apply all of these methods to analyze the spectacular and colourful paintings at the site called Pleito, found in California, USA. Pleito is one of the most complex painted sites in the world. It has hundreds of individual paintings with many colours, including different shades of red, black, white, yellow, orange, green, and blue. This is the widest colour palette of any known site in North American and, importantly, it has multiple panels where paintings have been placed over earlier ones. This kind of overpainting, known as superimposition, presents the greatest challenge to rock-art researchers in their attempts to understand painted art found in the landscape. Even though such complex paintings are challenging, they offer to the archaeologist who can unravel the sequence the greatest chance of understanding the development of paintings through time. Within the site of Pleito, a panel known to researchers as the 'Gordian Knot' is the most elaborate panel found there, making it one of the most complex prehistoric panels found anywhere in the world. The name of this project is derived from this panel, and so Pleito and its complex sequences of overpainting executed in various colours is an ideal case to disentangle the history of painting events. The method employed will integrate a range of portable technologies including portable X-Ray Fluorescence, portable Raman Spectroscopy, Highlight Reflectance Transformation, dStretch digital photography, and portable digital laser scanning to unravel the sequence of painting that makes up one of the most complex sites found anywhere in the world. These techniques will help address questions concerning traditions of pigment use and give insights into the role of the art within Native society. The project includes a state-of-the-art website with a 3-D recreation to be housed at the California State University, Channel Islands, offering an alternative to site visitation as a means to experience the site without risk of damaging the ancient paintings. Also, a new conditional assessment will compare degradation of the site to a 2003 baseline report to see how much of the paintings have recently eroded away: finally, a series of experiments combining different pigments with different types of binding agents will give us material to test with both lab based and portable equipment in the creation of a spectral database: this will give us a series of different chemical readings to compare with the actual paintings and allow researchers across the world to compare results from their discoveries with the Gordian Knot Spectral Databasee