Welcome to the Web Page for Hector Neff

Professor of Anthropology and Research Scientist, IIRMES, CSULB.

 

One of my main research interests has been the application of chemistry-based provenance determination in archaeology. Up until June, 2002, I was Senior Research Scientist at the Missouri University Research Reactor (MURR), where I was involved in a program that does instrumental neutron activation analysis (INAA) for archaeological projects. The program is still going strong under the direction of my colleague, Michael D. Glascock. Mike has a very informative web page that describes INAA, the MURR Archaeometry program, and all of the productive research that has been done there (click here).

 

Here at Cal State Long Beach, my attention has shifted to using ICP-MS for chemical characterization. CSULB ICP-MS instruments are housed within IIRMES (the Institute for Integrative Research in Materials, Environments, and Societies), and include a Perkin-Elmer 6100 DRC and a brand new GBC Optimass time-of-flight (TOF) instrument. There is also a New Wave UP-213 laser ablation system dedicated primarily to archaeological applications.

 

The TOF is the ideal ICP-MS instrument to connect to a laser-ablation sampling system, which produces an input sample stream that is less stable than a liquid stream. The TOF samples whole packets of ions coming out of the ICP torch, 30,000 times per second, then integrates these samples over some period of time. Initial experiments indicate reasonably good replicability with integration times as low as 0.2 seconds. That means that we can measure almost every element in the periodic table in a sample so small that it is consumed by a laser blast that last only one fifth of a second. Applications involving very small particles or very thin pigment layers on ceramics are some of the exciting analytical applications possible with LA-TOF-ICP-MS. 

 

Here are some highlights of our archaeological science programs at CSULB:

 

·        We recently received a NSF grant that funds short-term visits by academic researchers and subsidizes analyses for archaeological purposes. For more details, take a look at the announcement on the IIRMES web page. Please contact me (hneff@csulb.edu) if you have a potential application and would like to arrange to visit IIRMES. I have a table that lists some of the LA-ICP-MS projects completed or ongoing through the IIRMES lab.

 

·        We have a nascent obsidian source database for California and will use LA-TOF-ICP-MS to determine sources of California obsidian artifacts for CRM or other research purposes. One of the exciting possibilities with LA-TOF-ICP-MS is the ability to determine sources for microdebitage down to less than 0.5 mm in size. At the other end of the size spectrum, we can put artifacts up to about 5 cm x 2 cm in the laser-ablation chamber, but for larger artifacts we will need to remove a small piece for analysis. The scar left by ablation is approximately 0.1 x 0.5 mm, which makes it all but invisible to the naked eye. We will analyze obsidians for $30 per sample, but we have a minimum charge of $250, so we recommend submitting at least 9 artifacts for analysis.

 

·        LA-TOF-ICP-MS is also useful for tephrochronology, as demonstrated by a pilot project undertaken with Jeff Knott, CSU Fullerton. Here are two plots of data obtained for four Death Valley tephra beds. Each data point was obtained from a glass shard less than 0.5 mm diameter on an electron-microprobe sample slide.

 

 

A current debate on the Olmec:

 

A recent INAA study of Olmec pottery has fueled renewed debate between adherents of two contrasting metaphorical summaries of Early Formative Mesoamerican civilization. One metaphor holds that the Gulf lowland Olmec were Mesoamerica’s “mother culture”; the opposing metaphor holds that Early Formative Mesoamerica was made up of roughly equivalent “sister cultures”. Here are some recent installments in the debate:

 

·        An article from Science by Blomster et al. (2005) reporting results of a INAA study Olmec pottery.

·        A perspective by Richard Diehl in the same issue of Science.

·        A response to a misguided critique of the INAA study by various “sister culture” proponents (from Latin American Antiquity, March 2006; this is a pre-publication manuscript).

·        A second round of response to fresh misrepresentations of the INAA study (from Latin American Antiquity, March 2006; this is a pre-publication manuscript)