An alliance to address the Red Sea's record of past global climate and earthquakes

沙漠气候的蒸发导致红海优先失去同位素O-16而不是O-18，因此红海水域倾向于富集O-18。这种趋势在全球海平面较低的时候尤其明显，因为红海与印度洋的连接非常小（在曼德海峡）。由远洋生物壳形成的沉积物记录了这种氧同位素信号。在海洋学模型的帮助下，研究人员利用这一点来计算过去50万年海平面是如何波动的。与此同时，其他信息（地震反射图像）显示，红海内的沉积物在上新世（可以追溯到530万年前）被洋流移动。这种情况在今天一般不会发生，因为红海的深水流动非常缓慢。与卡明斯基教授的新伙伴关系将使我们能够确定20世纪70年代深海钻探项目收集的遗留岩心中沉积物的年代，这些沉积物从那时起就没有使用过。我们将在贝壳未被严重改变的地方测量氧同位素，弄清楚贝壳是否记录了变化的洋流信息，并测量来自大陆的更细颗粒的大小，这也是测量洋流速度的潜在指标。氧同位素将用于帮助评估上新世和更新世早期海平面的变化。与卡米尼斯基教授的合作对于确定这些变化的时间以及利用贝壳来确定电流至关重要。海平面的变化也会影响红海海床上沉积物的强度，因为更极端的盐度往往会导致文石（碳酸钙的一种形式）直接从水中沉淀下来。与Jonsson教授一起，我们将利用这种趋势来确定地震反射图像中分层的时间，这些图像是由一个深拖曳在海床附近的设备收集的（深拖曳使该设备收集的图像比我们通常从海面收集的图像清晰得多）。这将使我们第一次能够评估红海海床下的巨大断层目前活动的程度和/或它们上次滑动的时间。这一点很重要，因为许多沿海城市靠近对人口构成威胁的主要活动断层，这是约翰逊教授利用卫星方法研究的另一个重点。如果我们能计算出地震发生的频率，这将有助于灾害规划。在红海演示这种方法可能会引起人们对在其他一些地方使用这种方法的兴趣，从而产生更广泛的效益。

Evaporation in the desert climate causes the Red Sea to lose the isotope O-16 preferentially over O-18 and as a result Red Sea waters tend to be enriched in O-18. This tendency is particularly enhanced at times when global sea-levels were lower because the connection of the Red Sea with the Indian Ocean is very small (at Bab el Mandeb Strait). The sediments formed of the shells of pelagic organisms record this oxygen isotope signal. Researchers have used this, with the help of oceanographic models, to work out how sea-level has fluctuated for the past 500 thousand years. Meanwhile, other information (seismic reflection images) has revealed that the sediments within the Red Sea were being moved around by currents in the Pliocene, a period extending back to 5.3 million years. This generally does not happen today, as the Red Sea deep waters are very slow moving.A new partnership with Prof. Kaminski will allow us to date the sediments in legacy cores collected in the 1970s by the Deep Sea Drilling Project and left unused since then. We will measure oxygen isotopes where shells have not been badly altered, work out if the shells record information on the varying currents and measure the sizes of finer particles originating from the continents, also a potential measure of current speeds. Oxygen isotopes will be used to help evaluate the variability of sea-level in the Pliocene and earlier Pleistocene. The work with Prof. Kaminiski will be essential for working out the timing of these changes, as well as the use of shells to determine currents.Changes of sea-level also affect the strength of the sediments on the bed of the Red Sea because more extreme salinity tends to lead to aragonite (a form of calcium carbonate) precipitating directly from the water. With Prof. Jonsson, we will exploit this tendency to date the layering in seismic reflection images due to be collected with a device that is towed deeply near the seabed (towing deeply allows the device to collect much sharper images than we would normally get by collecting them from the sea surface). This will allow us, for the first time, evaluate the extent to which giant faults underlying the bed of the Red Sea are presently active and/or when they last slipped. This is important, as many coastal cities lie close to major active faults that present a threat to their populations, another focus of Prof. Jonsson's work with satellite methods. If we could work out the frequency with which earthquakes occur, this could help with disaster planning. Demonstrating the method in the Red Sea could create interest in using it in some of these other locations and thus be of broader benefit.