(—THIS SIDEBAR DOES NOT PRINT—)

DESIGN GUIDE

This PowerPoint 2007 template produces a 44”x44”

presentation poster. You can use it to create your research

poster and save valuable time placing titles, subtitles, text,

and graphics.

We provide a series of online tutorials that will guide you

through the poster design process and answer your poster

production questions. To view our template tutorials, go

online to PosterPresentations.com and click on HELP DESK.

When you are ready to print your poster, go online to

PosterPresentations.com

Need assistance? Call us at 1.510.649.3001

QUICK START

Zoom in and out As you work on your poster zoom in and out to the

level that is more comfortable to you. Go to VIEW >

ZOOM.

Title, Authors, and Affiliations Start designing your poster by adding the title, the names of the

authors, and the affiliated institutions. You can type or paste text

into the provided boxes. The template will automatically adjust the

size of your text to fit the title box. You can manually override this

feature and change the size of your text.

TIP: The font size of your title should be bigger than your name(s)

and institution name(s).

Adding Logos / Seals Most often, logos are added on each side of the title. You can insert

a logo by dragging and dropping it from your desktop, copy and

paste or by going to INSERT > PICTURES. Logos taken from web sites

are likely to be low quality when printed. Zoom it at 100% to see

what the logo will look like on the final poster and make any

necessary adjustments.

TIP: See if your school’s logo is available on our free poster

templates page.

Photographs / Graphics You can add images by dragging and dropping from your desktop,

copy and paste, or by going to INSERT > PICTURES. Resize images

proportionally by holding down the SHIFT key and dragging one of

the corner handles. For a professional-looking poster, do not distort

your images by enlarging them disproportionally.

Image Quality Check Zoom in and look at your images at 100% magnification. If they look

good they will print well. If they are blurry or pixelated, you will

need to replace it with an image that is at a high-resolution.

ORIGINAL DISTORTED

Corner handles

Go

od

pri

nti

ng

qu

alit

y

Bad

pri

nti

ng

qu

alit

y

QUICK START (cont. )

How to change the template color theme You can easily change the color theme of your poster by going to

the DESIGN menu, click on COLORS, and choose the color theme of

your choice. You can also create your own color theme.

You can also manually change the color of your background by going

to VIEW > SLIDE MASTER. After you finish working on the master be

sure to go to VIEW > NORMAL to continue working on your poster.

How to add Text The template comes with a number of pre-

formatted placeholders for headers and text

blocks. You can add more blocks by copying

and pasting the existing ones or by adding a

text box from the HOME menu.

Text size Adjust the size of your text based on how much content you have to

present. The default template text offers a good starting point.

Follow the conference requirements.

How to add Tables To add a table from scratch go to the INSERT menu and

click on TABLE. A drop-down box will help you select

rows and columns.

You can also copy and a paste a table from Word or

another PowerPoint document. A pasted table may need

to be re-formatted by RIGHT-CLICK > FORMAT SHAPE,

TEXT BOX, Margins.

Graphs / Charts You can simply copy and paste charts and graphs from Excel or

Word. Some reformatting may be required depending on how the

original document has been created.

How to change the column configuration RIGHT-CLICK on the poster background and select LAYOUT to see

the column options available for this template. The poster columns

can also be customized on the Master. VIEW > MASTER.

How to remove the info bars If you are working in PowerPoint for Windows and have finished your

poster, save as PDF and the bars will not be included. You can also

delete them by going to VIEW > MASTER. On the Mac adjust the

Page-Setup to match the Page-Setup in PowerPoint before you

create a PDF. You can also delete them from the Slide Master.

Save your work Save your template as a PowerPoint document. For printing, save as

PowerPoint or “Print-quality” PDF.

Print your poster When you are ready to have your poster printed go online to

PosterPresentations.com and click on the “Order Your Poster”

button. Choose the poster type the best suits your needs and submit

your order. If you submit a PowerPoint document you will be

receiving a PDF proof for your approval prior to printing. If your

order is placed and paid for before noon, Pacific, Monday through

Friday, your order will ship out that same day. Next day, Second day,

Third day, and Free Ground services are offered. Go to

PosterPresentations.com for more information.

Student discounts are available on our Facebook page.

Go to PosterPresentations.com and click on the FB icon.

© 2015 PosterPresentations.com 2117 Fourth Street , Unit C

Berkeley CA 94710

posterpresenter@gmail.com RESEARCH POSTER PRESENTATION DESIGN © 2015

www.PosterPresentations.com

NWA 856: (Djel Ibone)

• Basaltic shergottite

• Discovered in South Morocco in April, 2001 [1]

• Found as single stone of 320 gm [1]

• Fresh, fine grained

• Covered with thin black-fusion crust

• Highly fractured

• Terrestrially less weathered as a desert find [1]

• Crystallization age:

150 ± 32 Ma (Rb-Sr isotope system) and 186 ± 24 Ma (Sm-Nd isotope system) [2]

• Bulk rock oxygen isotope:

δ17O = +3.09 ‰, δ18O = +5.03 ‰, Δ17O = +0.47 ‰ [1]

Introduction

The purpose of this study is to constrain the crystallization history of NWA 856 using textural observations, crystallization sequence modeling and in-situ trace element analysis in order to understand differentiation in shergottite magmatic systems.

Objective

A polished thick section (15 x 13 x 2 mm) was used for EDX-elemental mapping by scanning electron microscope (SEM JEOL 7600F). An electron microprobe (EMP) Cameca SX100 was used to obtain in situ major element concentrations of each phase. Both instruments are located in the ARES division of NASA-Johnson Space Center.

Major, minor and trace element abundances in minerals were measured using a Varian 810 inductively coupled plasma mass spectrometer connected to a CETAC LSX-213 laser ablation system (LA-ICP-MS) in the department of Earth and Atmospheric Sciences of the University of Houston. The sizes of the analyzed spots were 20-100 µm in diameter. The software GLITTER was used to calculate concentrations. Analyses were normalized to CaO contents obtained from EMP analyses. Basalt glass BHVO-2G (USGS standard) was used for calibration while BIR-1G (USGS standard) was used as an external standard to monitor accuracy and reproducibility.

Analytical Techniques • Highly fractured

• Maskelynization

• Pyroxene dislocations and twins [3]

• Abundant impact melt pockets [4]

• Presence of stishovite and high silica glass [1, 4]

Mineralogy

Discussion and Conclusion

The results of petrography, EMP, LA-ICP-MS analyses and MELTS simulations are consistent with the findings of [1]. Pyroxene and spinel began to crystallize first. This was followed by a multistage crystallization sequence with plagioclase formation and final crystallization of phosphates and ilmenite. Pyroxene cores are not disturbed by alteration or shock but plagioclase was shocked into maskelynite with local incorporation of phosphates. NWA 856 closely resembles Shergotty and Zagami, but the lack of mesostasis, larger grain size, an abundance of impact melt pockets and minimal terrestrial weathering separate NWA 856 from any other basaltic shergottites.

References

[1] Jambon et al. (2002), MAPS, 37, 1147-1164.

[2] Brandon et al. (2004), LPSC XXXV, #1931.

[3] Leroux et al. (2004), MAPS, 39, 711-722.

[4] Leroux and Cordier (2006), MAPS, 41, 913-923.

[5] Asimow and Ghiorso (1998), AM, 83, 1127-1131.

Crystallization Sequence

1University of Houston, Houston TX 77204, USA, jferdous@uh.edu, 2Jacobs, NASA-Johnson Space Center, Mail Code X13, Houston TX 77058, USA, 3Dept. de Géologie, Université Libre de Bruxelles, 1050 Brussels, Belgium.

J. Ferdous1, A. D. Brandon1, A. H. Peslier2 and Z. Pirotte3

Basaltic Shergottite NORTHWEST AFRICA 856: Differentiation of a

Martian Magma

Figure 1: NWA 856 showing thin fusion crust and

interior basaltic texture. (Photo Courtesy: Bruno

Fectay and Carine Bidant)

Figure 3: Multi-element (Si, Mg, Fe, Ca, Ni, S) map of NWA 856 obtained from Energy Dispersive X-ray (EDX) analysis.

In-Situ Trace-Elements

Figure 11: Crystallization sequence based on MELTS simulation of isobaric equilibrium and fractional crystallization.

Figure 12: CI-chondrite normalized measured REE-patterns of zoned clinopyroxenes, maskelynites, phosphates and bulk composition.

Figure 13: CI-chondrite normalized REEs, LILE, HFSE and transitional metals of zoned clinopyroxenes, maskelynites, phosphates with increasing compatibility from left to right.

Figure 4: BSE-images of different mineral phases: major phases a) zoned pigeonite (Pgt) b) zoned augite (Aug) c) maskelynite (Mask) and minor phases d) ulvöspinel (Ulvo), ilmenite (Ilm) and amorphous K-feldspar (FK) e) phosphates (P) f) sulfides (S).

Figure 5: Triangular diagram of pyroxene compositions of NWA 856 compared to Shergotty and compositional evolution of NWA 856 obtained from MELTS.

Figure 6: Range of of minor element compositions versus Mg# (Mg/(Mg+SFe2+)) in pyroxenes of NWA 856. All oxides are in wt%. Here, red squares are pigeonites and blue diamonds are augites.

Figure 7: Triangular plotting of the feldspar compositions of NWA 856 with compositional evolution obtained from MELTS.

Figure 8: Maskelynite compositions show localized Si-enrichment indicating contribution from evolved phases such as K-feldspar and SiO2.

Figure 9: Shock features of NWA 856: pyroxene dislocation and twins, shocked impact melt (IM) and late stage crystalized melt pocket (MP) (from left to right).

The crystallization sequence of NWA 856 is derived from textural relationships and compared to results from MELTS simulations [5] using NWA 856 bulk composition from [1] as initial composition. MELTS simulation, result in the same crystallization sequences at 4 kbar and 5 kbar and those run under fractionation conditions are most consistent with our textural analysis.

Shock Features

NWA 856 is an enriched basaltic shergottite with flat rare earth element (REE)-pattern similar to Shergotty and Zagami [1]. The absence of positive Ce-anomalies and lower contents of Cs, Ba and Sr in all phases when compared to other desert finds indicate that NWA 856 is the least affected by terrestrial weathering and alteration.

Figure 10: Crystallization sequence based on textural and compositional observations.

45% (pigeonte)

23% (augite)

23% plagioclase

1% phosphate

2% melt pocket 6% other phases

Figure 2: Major phases and modal abundances of

NWA 856 [1].

0.1

1

10

100

1000

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Sam

ple

/CI-

cho

nd

rite

REEs Pigeonite core

Pigeonite rim

Augite core

Augite rim

High-P Maskelynite

Low-P Maskelynite

Merrillite

Apatite

Bulk rock (Jambon,2002)

0.0001

0.001

0.01

0.1

1

10

100

1000

Rb Ba Th U Nb Ta La Ce Pr Sr Nd Zr Hf Sm Eu Ti Gd Tb Dy Y Ho Er Tm Yb Lu Co Sc Cr Ni

Sam

ple

/CI-

Ch

on

dri

te

Trace elements (increasing compatibility)

Pigeonite core

Pigeonite rim

Augite core

Augite rim

High-P Maskelynite

Low-P Maskelynite

Merrillite

Apatite

700 800 900 1000 1100 1200 1300 1400

T (⁰C)

Ulvöspinel

Clinopyroxene

Plagioclase

Phosphate

Ilmenite

Silica+glass

Sulfide

900 1000 1100 1200 1300 1400

T (⁰C) Equilibrium at 4 kb

Ulvöspinel

Clinopyroxene

Feldspar

Silica

Ilmenite

Olivine

1000 1100 1200 1300 1400

T (⁰C)

Fractionation at 4 kb 88% crystallized

Ulvöspinel

Clinopyroxene

Feldspar

Silica