Laboratory Specials


Trace Element Analysis & Thermobarometry

TiZrBy combining counts from multiple spectrometers that use 'oversized' PET and LIF crystals (providing high x-ray count rates), we can achieve detection limits in the 20-40 ppm range, suitable for application of the Zr-in-rutile, Zr-in-sphene, and Ti-in-Quartz (TitaniQ) thermometers in a range of rock types.

Wark D. A. and Watson E. B. (2006) TitaniQ: A titanium-in-quartz geothermometer. Contributions to Mineralogy and Petrology 152(6), 743-754.

Watson E. B., Wark D. A., and Thomas J. B. (2006) Crystallization thermometers for zircon and rutile. Contributions to Mineralogy and Petrology 151(4), 413-433.

Thomas, J. B., Watson, E. B., Spear, F.S., Shemella, P. T., Nayak, S. K., and Lanzirotti, A. (2010) TitaniQ under pressure: the effect of pressure and temperature on the solubility of Ti in quartz. Contributions to Mineralogy and Petrology, DOI 10.1007/s00410-010-0505-3.


REE/U/Th Phosphates: Monazite & Xenotime

Our instrument is configured for simultaneous analysis of all rare earth elements plus U, Th, and Pb. This allows precise determination of chemical ages from monazite, and of temperatures of equilibration for monazite-xenotime assemblages.

Pyle J. M., Spear F. S., Rudnick R. L., and McDonough W. F. (2001) Monazite-xenotime-garnet equilibrium in metapelites and a new monazite-garnet thermometer. Journal of Petrology 42(11), 2083-2107.

Pyle J. M., Storm L. C., Spear F. S., Wark D. A., and Daniel C. G. (2005) Contributions to precision and accuracy of monazite microprobe ages. American Mineralogist 90(4), 547-577.

Spear F. S., Pyle J. M., and Cherniak D. (2009) Limitations of chemical dating of monazite. Chemical Geology 266, 218-230.


Cathodoluminescence Imaging & Spectroscopy

TiZrWith Gatan's monoCL3 imaging and spectroscopy system, we can collect high-resolution, cathodoluminescence imagmes and spectra - even from crystals with weak CL emissions, such as quartz.

Wark D. A., Watson E. B., Hildreth W., Spear F. S., and Cherniak D. J. (2007) Pre-eruption recharge of the Bishop magma system. Geology 35(3), 235-238.>

 

EMP Analysis & Imaging

Quick Link: User schedule

Our Cameca SX-100 electron microprobe is used for chemical analysis and for electron or cathodoluminescence imaging of geological, metallurgical, ceramic, glass, and other materials.

SX-100SX-100

As seen on the National Geographic Channel's "Naked Science: Stone Age Apocalypse"

Laboratory Policies & Procedures (pdf)

Access

• This instrument was funded in part by the National Science Foundation and is available to all Rensselaer faculty, staff, and students as well as external academic and industry collaborators and researchers after approval by the Laboratory Manager.

• Non-Rensselaer users generally will only be able to access the facilities and instrumentation during regular business hours (M-F 8am-5pm) unless pre-approved for after-hours work by the Laboratory Manager. A list of our spectrometer crystals and rates are available here:

RPI Crystals.pdf

Rates shown are for FY 2013 and are subject to change without notice:

Academic Users: $45/hour
Operational Assist: + $25/hour
24 hours: $540 (50% discount)

Non-Academic Rates: $150/hour
Operational Assist: + $50/hour
24 hours: $1500

If you would like to use our facility, please fill out the authorization form and return it to the Lab Manager:

User Authorization Form.pdf

Training

• Users must receive proper training before being permitted access to the equipment. Training is provided by the Laboratory Manager.

• Untrained users may use the equipment if assisted by the Laboratory Manager (Additional fee applies).

• Unsupervised use of equipment by advanced users is permitted pending approval of the Laboratory Manager and passing a written exam based on the in-house ‘User Guide’.

Scheduling

• Advanced reservations are required prior to instrument usage. Times are reserved by contacting the Laboratory Manager. The user-schedule calendar is available below.

• Two time slots are available for any given day:
Slot 1: 0900 – 1700 (5 pm)
Slot 2: 1700 – 0900 (the following morning)

• Cancellations must be made at least 24 hours in advance or a $200.00 cancellation fee will be charged.

• Users shall have a grace period of 30 minutes from the scheduled start time to use the equipment. Failure to begin usage after 30 minutes will result in a forfeited timeslot and a $200.00 cancellation charge.

• Users may request both time slots (24 hour usage), but use must start at the beginning of Slot 1 (0900) or Slot 2 (1700) in order to avoid a forfeited timeslot and cancellation fee.

Cleaning Up

• Users are responsible for keeping the equipment areas safe and clean. Failure to do so will result in loss of usage privileges.

• Users are responsible for removing samples from the instrument. Samples should also either be stored outside BC09A (in the sample preparation area) or removed from the lab entirely when not in use.

Billing

• Users must fill out a User-Authorization Form and submit it to the Laboratory Manager prior to equipment use unless otherwise instructed: User Authorization Form.pdf


Questions about the facilities, capabilities or scheduling should be directed to the Laboratory Manager, Dr. Jared Singer. View the user-schedule here.

How does it work?

The electron microprobe uses a focused electron beam to generate characteristic x-rays from a flat, polished, solid material. The intensity of these x-rays is compared to those produced on well-characterized materials in order to determine composition.

We can characterize the concentrations of elements heavier than boron (Z=5), in some instances to concentrations as low as 10's of parts per million.

We can also generate two dimensional maps showing the relative changes in intensity resulting from differences in composition. The example below shows the distribution of fluorine in a mica

F in Mica

 

Unfamiliar with these techniques? Click here for a general introduction.

 

Contact Dr. Jared Singer (Ph: 518.276.4095) to sign up for probe time: