Archaeology News Online

An international team of scientists digging in a sea cave in Indonesia has discovered the world's most pristine record of tsunamis, a 5,000-year-old sedimentary snapshot that reveals for the first time how little is known about when earthquakes trigger massive waves. Researchers stand in the trench of a sea cave [Credit: Earth Observatory of Singapore] "The devastating 2004 Indian Ocean tsunami caught millions of coastal residents and the scientific community off-guard," says co-author Benjamin Horton, a professor in the Department of Marine and Coastal Sciences at Rutgers University-New Brunswick. "Our geological record from a cave illustrates that we still cannot predict when the next earthquake will happen." "Tsunamis are not evenly spaced through time," says Charles Rubin, the study's lead author and a professor at the Earth Observatory of Singapore, part of Nanyang Technological University. "Our findings present a worrying picture of high...

In the shallow waters of a sea in northern China 500 million years ago, a dazzling new array of creatures was swimming: part of an explosion of animal diversity that would forever change the course of life on Earth. Quietly, in the seabed beneath them, another revolution was underway. Close-up view of fossilized branching burrows preserved in rock formed from an ancient seabed  in what is now northern China [Credit: University of Saskatchewan] For perhaps the first time, tiny creatures were pushing their way through the sediment to create complex mazes of burrows, slowly but profoundly altering the environment around them. Evidence of these early "ecosystem engineers" was published in Scientific Reports by researchers from the University of Saskatchewan (USA) and Henan Polytechnic University in China. The floors of Earth's ancient oceans looked very different than they do today, said Luis Buatois, a professor in the US Department of Geological Sciences and one of the st...

Using a combination of fossils and chemical markers, scientists have tracked how a period of globally low ocean-oxygen turned an Early Jurassic marine ecosystem into a stressed community inhabited by only a few species. Before the low oxygen period, bivalves were larger and more numerous [Credit: The University of Texas at Austin/ Rowan Martindale] The research was led by Rowan Martindale, an assistant professor at The University of Texas at Austin Jackson School of Geosciences, and published in print in Palaeogeography, Palaeoclimatology, Palaeoeconology . The study was co-authored by Martin Aberhan, a curator at the Institute for Evolution and Biodiversity Science at the Natural History Museum in Berlin, Germany. The study zeroes in on a recently discovered fossil site in Canada located at Ya Ha Tinda Ranch near Banff National Park in southwest Alberta. The site records fossils of organisms that lived about 183 million years ago during the Early Jurassic in a shallow sea that once co...

Why did life on Earth change from small to large when it did? Researchers from the University of Cambridge and the Tokyo Institute of Technology have determined how some of the first large organisms, known as rangeomorphs, were able to grow up to two metres in height, by changing their body size and shape as they extracted nutrients from their surrounding environment. Artist's impression of rangeomorphs [Credit: Jennifer Hoyal Cuthill] The results, reported in the journal Nature Ecology and Evolution , could also help explain how life on Earth, which once consisted only of microscopic organisms, changed so that huge organisms like dinosaurs and blue whales could ultimately evolve. Rangeomorphs were some of the earliest large organisms on Earth, existing during a time when most other forms of life were microscopic in size. Some rangeomorphs were only a few centimetres in height, while others were up to two metres tall. These organisms were ocean dwellers that lived during the Ediaca...

The results, which include information during the last glacial and interglacial periods, showed that relief from the current dry spell across the interior of the Middle East is unlikely within the next 10,000 years. Graphs showing data measured from two stalagmites from QK Cave in Iran in comparison with other proxy records.  A: Blue line is δ18Oc from QK14 and green line is QK8. Both are from the same came but ~75m apart from one  another. Primary driver for long scale climate change is orbital configuration.  Colored diamonds represent U-Th  age tie points with their associated error bars. B: Orange line is δ18Ow measured in the NGRIP ice core.  C: Purple line is δ18Oc measured in Sanbao Cave, China, part of the Hulu Cave record (Wang et al., 2008).  D: Dark blue line is δ18Oc measured in Soreq Cave, Israel (Bar-Matthews et al., 2003). E: Light blue line is δ18Oc measured in foraminifera collected from deep sea sediment cores (Lisiecki et al., 2005) ...

A peat bog in Romania provides a new insight into our knowledge of when the Sahara began to transform from grassland into the desert we know today, and the impact this had on dust deposition within Eastern Europe. Saharan dust over the Mediterranean Sea [Credit: Northumbria University] Using carbon dating and chemical analysis, researchers from Northumbria University, Newcastle have shown that significant changes in dust levels occurred in Romania around 6,100 years ago, despite the climate in Eastern Europe being relatively wet at this time, indicative of an extraregional source of such dust, most likely to be from the Sahara. This discovery is valuable new evidence of the impact changes in the climate and vegetation of North Africa may have on dust in Europe and may allow climate modellers to better understand the movement of dust and the impact of desertification, both in the past and the future. The research was led by Jack Longman, a Geography PhD student at Northumbria. His resul...

Scientists have identified patterns in Earth's magnetic field that evolve on the order of 1,000 years, providing new insight into how the field works and adding a measure of predictability to changes in the field not previously known. Supercomputer model of Earth's magnetic field [Credit: NASA] The discovery also will allow researchers to study the planet's past with finer resolution by using this geomagnetic "fingerprint" to compare sediment cores taken from the Atlantic and Pacific oceans. Results of the research, which was supported by the National Science Foundation, were recently published in Earth and Planetary Science Letters . The geomagnetic field is critical to life on Earth. Without it, charged particles from the sun (the "solar wind") would blow away the atmosphere, scientists say. The field also aids in human navigation and animal migrations in ways scientists are only beginning to understand. Centuries of human observation, as well as the g...

Climate evolution shows some regularities, which can be traced throughout long periods of earth's history. One of them is that the global average temperature and the carbon dioxide concentration in the atmosphere usually go hand-in-hand. To put it simple: If the temperatures decline, the CO2 values also decrease and vice versa. Model of an island volcano. During the last transition to glacial conditions the decreasing pressure  at the seafloor could have induced increased lava- and carbon dioxide emissions  [Credit: Jorg Hasenclever] However, there are exceptions. An international team of scientists led by the GEOMAR Helmholtz Centre for Ocean Research Kiel and the Alfred-Wegener-Institute Helmholtz Centre for Polar and Marine Research has now discovered a possible cause for such irregularities. An example is the last transition to glacial conditions. At approximately 80,000 years ago the temperatures declined, but the amount of carbon dioxide in the atmosphere remained relati...

Some good scientific sleuthing by an undergraduate at The University of Texas at Austin has helped rewrite one of the earliest chapters in the planet's evolutionary history. The research, led by the UT Jackson School of Geosciences, has shown that the millipede thought to be the world's oldest known air-breathing land creature is in fact about 14 million years younger than previously thought and cannot be the original land breather. Examples of zircon grains used in a University of Texas at Austin study that showed the animal thought to be the oldest  land-based air breather is younger than thought. Grain numbers and ages are indicated by the numbers  [Credit: University of Texas Jackson School of Geosciences] The paper was published in the journal PLOS ONE . The study focuses on a species of millipede called Pneumodesmus newmani, which was thought to have been breathing air on solid ground during the late Silurian period some 428 million years ago. All other animal fossils di...

In the shallow waters of a sea in northern China 500 million years ago, a dazzling new array of creatures was swimming: part of an explosion of animal diversity that would forever change the course of life on Earth. Quietly, in the seabed beneath them, another revolution was underway. Close-up view of fossilized branching burrows preserved in rock formed from an ancient seabed  in what is now northern China [Credit: University of Saskatchewan] For perhaps the first time, tiny creatures were pushing their way through the sediment to create complex mazes of burrows, slowly but profoundly altering the environment around them. Evidence of these early "ecosystem engineers" was published in Scientific Reports by researchers from the University of Saskatchewan (USA) and Henan Polytechnic University in China. The floors of Earth's ancient oceans looked very different than they do today, said Luis Buatois, a professor in the US Department of Geological Sciences and one...

An international team of scientists digging in a sea cave in Indonesia has discovered the world's most pristine record of tsunamis, a 5,000-year-old sedimentary snapshot that reveals for the first time how little is known about when earthquakes trigger massive waves. Researchers stand in the trench of a sea cave [Credit: Earth Observatory of Singapore] "The devastating 2004 Indian Ocean tsunami caught millions of coastal residents and the scientific community off-guard," says co-author Benjamin Horton, a professor in the Department of Marine and Coastal Sciences at Rutgers University-New Brunswick. "Our geological record from a cave illustrates that we still cannot predict when the next earthquake will happen." "Tsunamis are not evenly spaced through time," says Charles Rubin, the study's lead author and a professor at the Earth Observatory of Singapore, part of Nanyang Technological University. "Our findings present a worrying picture of high...

Using a combination of fossils and chemical markers, scientists have tracked how a period of globally low ocean-oxygen turned an Early Jurassic marine ecosystem into a stressed community inhabited by only a few species. Before the low oxygen period, bivalves were larger and more numerous [Credit: The University of Texas at Austin/ Rowan Martindale] The research was led by Rowan Martindale, an assistant professor at The University of Texas at Austin Jackson School of Geosciences, and published in print in Palaeogeography, Palaeoclimatology, Palaeoeconology . The study was co-authored by Martin Aberhan, a curator at the Institute for Evolution and Biodiversity Science at the Natural History Museum in Berlin, Germany. The study zeroes in on a recently discovered fossil site in Canada located at Ya Ha Tinda Ranch near Banff National Park in southwest Alberta. The site records fossils of organisms that lived about 183 million years ago during the Early Jurassic in a shallow sea that once co...