Navigation Links
A thesis characterizes marine conditions of Aralar mountain range of 120 million years ago

This release is available in Spanish.

The Early Aptian (120 million years ago) was an age of intense volcanic activity on Earth, eruptions that emitted large amounts of CO2 into the atmosphere, thus causing a revolution in the carbon cycle. As a consequence, great changes happened in the whole of the terrestrial system. Researcher Mara Isabel Milln has studied how these changes happened in the marine environment of the Aralar mountain range (at that time it was under the sea) in the Basque Country, and found more than one surprise. She presented her conclusions in her PhD thesis at the University of the Basque Country (UPV/EHU).

Ms Milln's thesis is entitled Record of Palaeoceanographic changes during the Early Aptian of the Aralar mountain range. Given its geological characteristics, Ms Milln suspected that the changes that took place in the Early Aptian period must have left traces in the sediments of the Aralar mountain range, which straddles the Basque provinces of Gipuzkoa and Navarre. She began to study the outcrops in detail. The researcher observed that the materials representing this period in Aralar are more significant than those studied to date, and this was the first surprise of this thesis. While in other parts of the world the sedimentary series of the Early Aptian that can be studied are some 20 metres thick, Ms Milln found up to 1,000 metres in Aralar.

An unparalleled event

One of the principal global changes that took place in the oceans of the Early Aptian was that known as OAE1a (Oceanic Anoxic Event 1a); that is, a sudden reduction in maritime oxygen at the ocean beds. In order to show that this phenomenon also occurred in Aralar, Ms Milln employed a number of methodologies. On the one hand, she used ammonite fossils, which give very precise dates and which have been found in abundance in these sediments. She also made use of analytical techniques for identifying rock enriched with organic material. In fact, when something important happened in the atmosphere or in the ocean during that period, rocks known as black shales were deposited at the bottom of the sea. These rocks were enriched with organic material, leaving remains thereof in the sedimentary layers. Ms Milln also made use of stable isotopes of carbon, as their proportion depends on the origin and concentration of CO2 present at the time. It is precisely in the Early Aptian that a huge increase of volcanic-origin CO2 took place. She found evidence amongst the sedimentary rocks which were significant in terms of an OAE1 event, thus demonstrating that this phenomenon also had taken place in Aralar.

While looking for the OAE1, Ms Milln also came across another event which, to date, has only been found on Aralar. The point here is that she discovered an interval of rock enriched with organic material, which indicates an enormously significant geological event. However, the ammonites found in this interval show that this event does not correspond exactly to the period in which the OAE1 event occurred, but is a somewhat later (younger) event; from the Upper Early Aptian to be exact. Ms Milln believes it could be a sub-event within the more wide-ranging OAE1 one. It would be, therefore, a regional or local event, given that nothing similar has been found anywhere else to date, and it remains to be seen if anything equivalent does, in fact, exist.

Sudden collapse of the reef platform of Madotz

The biocalcification crisis is another of the representative phenomena of the changes in the Early Aptian. Specifically, in Madotz, in the south-east of the mountain range, there was a reef platform, equivalent to, for example, what is found in the coral reefs of Australia today. As the researcher explained, the biocalcification that commonly occurred on the reefs suddenly collapsed on this platform, coinciding with the OAE1a event and probably responding to an acidification of the oceans (as is happening today due to industrial-origin CO2). This, according to Ms Milln, is a clear reflection of the biocalcification crisis, given that the carbonated composition of the platform was drastically modified.


Contact: Amaia Portugal
Elhuyar Fundazioa

Related biology news :

1. Scientists unlock mystery in important photosynthesis step
2. Ancient remains put teeth into Barker hypothesis
3. Scientists find quantum mechanics at work in photosynthesis
4. High-throughput analysis of gene regulation, DNA synthesis in Cold Spring Harbor Protocols
5. Scripps Research team wins global race to achieve landmark synthesis of perplexing natural product
6. What came first in the origin of life? A study contradicts the metabolism first hypothesis
7. Extreme genes shed light on origins of photosynthesis
8. Light, photosynthesis help bacteria invade fresh produce
9. Facile synthesis of nanoparticles with multiple functions advanced in Singapore
10. Advance in understanding cellulose synthesis
11. Pliable proteins keep photosynthesis on the light path
Post Your Comments:
(Date:11/18/2015)... PHILADELPHIA , Nov. 18, 2015  As new ... in children, doctors and other healthcare providers face challenges ... counsel families and patients. In addition, as more children ... into a patient,s adulthood and old age. ... The Children,s Hospital of Philadelphia (CHOP) . ...
(Date:11/17/2015)... Paris from 17 th until ... from 17 th until 19 th November ... has invented the first combined scanner in the world which scans ... Until now two different scanners were required: one for passports ... on the same surface. This innovation is an ideal solution ...
(Date:11/17/2015)... LIVERMORE, Calif. , Nov. 17, 2015  Vigilant ... has joined its Board of Directors. ... Vigilant,s Board after recently retiring from the partnership at ... owning 107 companies with over $140 Billion in revenue.  ... performance improvement across all the TPG companies, from 1997 ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... ... November 25, 2015 , ... Jessica Richman and Zachary ... in their initial angel funding process. Now, they are paying it forward to ... early stage investments in the microbiome space. In this, they join other ...
(Date:11/24/2015)... ... November 24, 2015 , ... The United States Golf Association (USGA) today announced ... Section Award. Presented annually since 1961, the USGA Green Section Award recognizes an individual’s ... , Clarke, of Iselin, N.J., is an extension specialist of turfgrass pathology ...
(Date:11/24/2015)... DIEGO , Nov. 24, 2015 Halozyme Therapeutics, Inc. ... Healthcare Conference in New York on Wednesday, ... Helen Torley , president and CEO, will provide a corporate ... New York at 1:00 p.m. ET/10:00 a.m. PT ... and investor relations, will provide a corporate overview. --> ...
(Date:11/24/2015)... Mass. (PRWEB) , ... November 24, 2015 , ... ... to maintain healthy metabolism. But unless it is bound to proteins, copper is ... of Health (NIH), researchers at Worcester Polytechnic Institute (WPI) will conduct a systematic ...
Breaking Biology Technology: