AlphaDelta

12/14/2022

AlphaDelta is now rewritten in Swift with iOs, PadOS and MacOS apps -Here to download: http://itunes.apple.com/ca/app/id421377528?mt=8

NEW! AlphaDelta Android app can now be downloaded here:
https://play.google.com/store/apps/details?id=ca.ulaval.AlphaDelta.alpha_delta

09/19/2018

Just added to AlphaDelta:

H2O(l)-H2(g) and H2O(l)-CH4(g) form

Horibe Y, Craig H (1995) D/H fractionation in the system methane-hydrogen-water. Geochimica et Cosmochimica Acta 59:5209-5217.

11/29/2017

Just added to AlphaDelta, the theoretical sulfur isotope fractions for the sulfide-sulphate system from:
Eldridge DL, Guo W, Farquhar J (2016) Theoretical estimates of equilibrium sulfur isotope effects in aqueous sulfur systems: Highlighting the role of isomers in the sulfite and sulfoxylate systems. Geochimica et Cosmochimica Acta 195:171-200. doi: http://dx.doi.org/10.1016/j.gca.2016.09.021.

11/28/2017

Just added to AlphaDelta the equations from :

-Chacko T, Deines P (2008) Theoretical calculation of oxygen isotope fractionation factors in carbonate systems. Geochimica et Cosmochimica Acta 72:3642-3660.

&

-van Dijk J, Fernandez A, Müller IA, Lever M, Bernasconi SM (2018) Oxygen isotope fractionation in the siderite-water system between 8.5 and 62 °C. Geochimica et Cosmochimica Acta 220:535-551. doi: https://doi.org/10.1016/j.gca.2017.10.009.

12/28/2016

AlphaDelta updated with new equations:
Pollington AD, Kozdon R, Anovitz LM, Georg RB, Spicuzza MJ, Valley JW (2016) Experimental calibration of silicon and oxygen isotope fractionations between quartz and water at 250 °C by in situ microanalysis of experimental products and application to zoned low δ30Si quartz overgrowths. Chemical Geology 421:127-142.

Fernandez A, van Dijk J, Müller IA, Bernasconi SM (2016) Siderite acid fractionation factors for sealed and open vessel digestions at 70 °C and 100 °C. Chemical Geology 444:180-186. doi: http://dx.doi.org/10.1016/j.chemgeo.2016.10.015.

In addition, the S-isotope fractionations of Sakai (1968) have been recalculated by fitting theoretical data to ln 1000 alpha = a *10^6/T^2+b*10^3/T+c using the lm function of R software.

The oxygen isotope composition of siderites can be used to deduce the paleoenvironmental conditions under which the mineral formed. However, it is not clear whether the published fractionation factors (αCO2-siderite) for the acid digestion of siderites are appropriate for modern “on-line” sample pre...

10/27/2015

AlphaDelta updated today with new equations:
Golyshev SI, Padalko NL, Pechekin SA (1981) Fractionation of stable oxygen and carbon isotopes in carbonate systems. Geochemistry International 18: 85-99.
Carbon isotope fractionations recalculated by fitting a polynominal 1000/T equation (lm function, R software) on 1000 ln B (mineral) - 1000 ln B (CO2).

10/26/2015

AlphaDelta updated today with a new equation:
Saccocia PJ, Seewald JS, Shanks Iii WC (2015) Oxygen isotope fractionation in the portlandite–water and brucite–water systems from 125 to 450 °C, 50 MPa. Geochimica et Cosmochimica Acta 169: 137-151.

08/10/2015

AlphaDelta updated today with a new equation:
Dalou C, Le Losq C, Mysen BO (2015) In situ study of the fractionation of hydrogen isotopes between aluminosilicate melts and coexisting aqueous fluids at high pressure and high temperature – Implications for the δD in magmatic processes. Earth and Planetary Science Letters 426: 158-166.

04/26/2014

AlphaDelta has a new web address!

www2.ggl.ulaval.ca/cgi-bin/alphadelta/alphadelta.cgi

New: computing 1000 ln "alpha" returns a graph vs 10^6/T^2.

04/26/2014

AlphaDelta a une nouvelle adresse web!

www2.ggl.ulaval.ca/cgi-bin/alphadelta/alphadelta.cgi

Nouveauté: le calcul de 1000 ln "alpha" produit un graphique en fonction de 10^6/T^2.

AlphaDelta offre deux possibilités de calcul : 1) calcul du fractionnement isotopique (1000 ln α) à une température donnée (nouveau-avec graphique);2) calcul de la température d'équilibre isotopique pour une différence de composition (Δ). 1) compute the isotope fractionation (1000 ln α) for a given…

08/17/2012

A new version of AlphaDelta is now available on the iTunes Store.

What is NEW!

1) A function to export a .csv formatted file of your last computations and send it by email.
2) A history of your computations, can be managed, deleted.
3) Cool: the new version optimized for the iPad! check it now!

Go to http://itunes.apple.com/ca/app/alphadelta/id421377528?mt=8

or update your app to get the new functionalities!!

Have fun! isotopes are cooooool!

Get AlphaDelta on the App Store. See screenshots and ratings, and read customer reviews.