Paper alert – Molybdenum isotopes in basalts, and potential constraints on the redox state of subducted slabs

It's fresh off the press, Qasid Ahmad and co-authors (including yours truly) just published  a short paper at GPL ( here ) providing some constraints on the redox state of subducted slabs, using molybdenum isotopes. And yes, articles in Geochemical Perspective Letters are fully open-access, thanks to the EAG support.  Qasid's paper is titled "Molybdenum isotopes in plume-influenced MORBs reveal recycling of ancient anoxic sediments" Using this new work to re-activate this page, but note that i 've posted a short thread on twitter, check it out below. How do molybdenum isotope constrain the redox state of subducted slabs? Qasid Ahmad just published a short paper providing some constraints. Fully open access thanks to @EAG_ . Quick thread — Jabrane Labidi (@JabraneLabidi) October 20, 2022 The studied objects here are basalts dredged up on the South-Atlantic mid-ocean ridge. These basalts record well-known interactions between the sub-oceani

Jabrane Labidi - DEI effort at the EAG

I enthusiastically joined the Diversity, Equality, and Inclusion sub-group at the European Association of Geochemistry. Our goal will be to  "promote DEI initiatives that cultivate welcoming, kind, inspiring, and actively anti-discriminatory scientific cultures as well as safe, healthy, and supportive working environments. As such, the EAG DEI initiative shall serve as a model for STEM in optimizing participation of historically excluded and underrepresented peoples across all sectors, levels of employ, and positions of community leadership." This is an initiative to tackle racism and other biases in our academic circles. We hope to not only raise awareness on how gated geochemistry appears to be for underrepresented folks, but also to produce content describing key aspects of our problem at hand. We intend on discussing the intricate aspects of social reproduction within academia on a worldwide scale, but also with a special target on European institutions. We will host a n

Jabrane Labidi - Panorama nostalgia

  Doug Rumble, Ed Young, Lina Taenzer, myself, and Will Leavitt. circa 2018. Good old times. 

Jabrane Labidi - The black lives matter movement - challenging anti-black racism in academia

BLACK LIVES MATTER -  challenging the status quo in academia  In the wake of the murder of George Floyd and Breonna Taylor, academics must challenge their bias against our black peers. In this excellent, gut-wrenching piece,  here (absolute read), Charles D. Brown II shows that less than 2% of earth science bachelor's degrees in the US went to black students in 2017, the lowest rates among all STEM fields. The statistics do not exist in Europe due to a regressive legislation, but it would be reasonable to assume the numbers are comparable, at best, or probably even less favorable to black folxs in academia.  The geochemical society, through the leadership of Roberta Rudnick, decided to take a stand, which i commend. For the online goldschmidt of 2020, a town hall about racism was organized, and i had the privilege to say a few words about our issues in academia, and specifically in our field. I was joined by three brilliant early career scientists: Emily Cooperdock (USC), James Do

Jabrane Labidi - methane clumped

Lina Taenzer, Ed young, Will Leavitt and others (including yours truly) just published a nice article in GCA! we show that the methane clumped isotopologue signatures of biological methane is the result of an effect coined "combinatorial effect" by others. Basically, we conventionally calculate deviations of clumped signatures with respect to a stochastic distribution. We show that is some instances, the stochastic distribution is a poor representation of the isotopic budget in a given molecule. When that happens, the stochastic abundance of doubly-substituted isotopologues is over-estimated. This causes anomously low signatures in natural samples.  This doesn't prevent interpreting the negative anomalies in  CH 4 clumped signatures as tracers of biogenic methane, but this yields new information on the genesis of such peculiar deficits.  Hit me up for a pdf version of the article!  or find it here:

Nitrogen isotopologues - only at UCLA - Jabrane Labidi

The isotopologue 15N15N of di-nitrogen could be measured in natural samples only at UCLA, in Edward Young's laboratory, with the Panorama mass spectrometer (see picture below). Only a large-radius mass spectrometer such as the Panorama, unique in the world, may allow resolving 15N15N from other compounds. This work's success is entirely due to the beauty of this instrument! Will upload a picture of the Panorama at UCLA!

Nitrogen isotopologues reveal the origin of nitrogen in our planetary interior - Jabrane Labidi

Hi All,  We've published our work in the journal Nature. We show that we can eliminate the confounding effect of air contamination in volcanic and hydrothermal gases, for the specific case of nitrogen. By substracting air contamination, we derive the di-nitrogen (N 2 ) molecular weight in various mantle sources.  A new finding here is that various mantle sources, with variable 15N/14N ratios, have a near-constant N2/3He ratio. Because 3He is in the deep Earth is not recycled, the constant N2/3He ratios argue against nitrogen addition via subduction in various mantle sources.  We built a 2-box model to show how over 4.5 Ga, the mantle and air may have exchanged considerably less nitrogen than previously suggested. In other words, the possibility that mantle nitrogen is primordial can no longer be excluced. In this theory, nitrogen would have been inherited from the time the Earth was being built via planetary accretion.  proud of this work! Here is a link to vi