Project HERACLES : Fieldwork Part 2: 3D Laser Scanning , Finishing Gravity, and the Lady Beekeeper

Our lean mean FARO scanner

3D Laser Scanning: what is it and what can you do with that? A 3D scanner basically takes 100,000 or more samples per second of an (at best stationary) object using laser range-finding, providing a point cloud that can render a highly accurate reconstruction (especially with the addition of a camera). Our new scanner from FARO is smaller-faster-better (and lighter - it can be taken as a carry-on, for example, on an airplane). These types of (active) scans are most useful for reconstructions and as an aid to modeling - the uses are varied, ranging from architectural planning to crime scene investigations (heavily alluded to in Primary Fault) to archeological site investigations (featured in Shaky Ground). Here, for example, one of our published scans from Roman ruins in the middle of Cologne.

I reported last time about our cleaning efforts prior to scanning - absolutely essential for getting a good scan. Luckily the east wall in Tiryns and the north wall in Midea (no direct links to either of the sites - but these links are very useful for background information) were cleaned for us by the crews at both sites for which we are tremendously grateful (thanks to Frau Dr. Demakopoulou, former archeological director at Midea and Frau Dr. Papadimitriou, Eforia of the Argolis, also participants in the HERACLES project, for their organizational help).

The brawny man on the right made the Tiryns east wall pretty for scanning.

 The scanning crew Klaus-G. Hinzen and Gregor Schweppe (also the passive seismic crew - geoscientists must be flexible, versatile and photogenic - WORD!) have made a plan of attack that includes the use of opaque white balls on broomsticks (geophysicists are also resourceful!) placed between the fallen rocks on the wall(s). The balls allow near-perfect alignment of the side-by-side scans. 

Balls on broomsticks amid a Bronze Age Cyclopean wall

 The new scanner needs all of 10 minutes to do a complete 360 degree color scan and even less for black and white. There is barely enough time between scans for the crew to enjoy the spectacular view from Midea. 
 

A momentary respite from the heat and wind to cool the scanner

Heat and wind - significant wind - conspire to slow down and even stop the measurements, especially when the scanner begins to overheat (at around 60 degrees Celsius). But the car air-conditioner serves as a quick cooler-downer (creativity!), the only casualty being Gregor's temporarily frozen hands.

Meanwile, the gravity crew, Evi Seferou and I, finished with traipsing around the Midea acropolis, concentrate on taking gravity measurements at the bottom of the hill - gaining profiles from different directions. After finishing the northernmost reach of our N-S profile, we start out on an E-W dirt road that looks promising because it seems less frequented by vehicles. 

Before we'd gone a scant kilometer, we encountered the end of the road and the beekeepers, a Greek giagiá (and the last in the series) and her husband clad in thick white linen/cotton suits and wide-brimmed hats with face-protecting nets. Evi and I - standing just a few meters from the first of the bee boxes - are wearing black T-shirts. The bee man points at us (and the bees who are making passes at us) and tells us bees hate black. While we hurriedly take our last measurement, the man asks us if we are the ones who have come to count the bees. Instantly distracted (not that difficult, to be honest), I ask (through my translator Evi, of course), so how do you count bees? Turns out that you don't count the bees, you count the boxes - and there are approximately 10,000 bees in a box.

The Greek bee lady and a few of her bees

We adjourn just after and follow the beekeepers to their house in the village of Midea to purchase some of the honey. Because it is a Greek grandmother we are commanded to drink Fanta (you are much too thin! Drink! Drink!) and taste the honey (fabulous). 

The bee lady proceeds to show us pictures of her children (and grandchildren) and asks me questions in Greek, first in a very slow cadence and then louder and more insistent - the international solution to speaking to someone in a language they don't comprehend. Evi is trying not to pee her pants in laughter, especially as she's yelling back answers to the questions - repeatedly - while I try to smile nicely and look like I know what the hell is going on (all of the rapid conversation is not being translated to me - for which I'm grateful, I think). "Is she married!? Does she have any children!?" "Yes!" "She has a son!" And the Greek grandfather meanwhile is mumbling epithets ranging from the mismanagement by the government of everything to the end of civilization as we know it. After we pay for the honey and leave, I realize this is one of those moments that will live with me forever. And if I can't find a way to fit that into a story some way somehow, then I'm not much of a writer, am I?

The guards at Midea

The guards at Tiryns

A few days later, and it's already time to leave. We bid farewell to the environs, to the heat, to the culture, and to the helpful guards at both Midea and Tiryns

A free Greek spirit out for a stroll on Midea

A Helen of Troy contest? We never found out.

Fredocino: the only antidote to the searing Greek heat

HERACLES: Archeoseismology in Tiryns, Greece, Year 2

T-3 days and counting to take-off. Okay, geophysical field work is not as exciting as going into space, granted, but for a solid earth geophysicist, the earth's surface - and near surface - is not only The Final Frontier, it's the only frontier. Planetary, oceanic and atmospheric geophysicists - your frontier (and mileage) may vary.

The pile of things we have to load into our departmental VW Caddy is growing by the minute. Literally. Saturday we will hit the road, driving first from Bensberg, Germany to Ancona, Italy (it's where the calf bulges out on Italy's boot). Getting on the car ferry. Then after debarking from Patras, Greece, driving the rest of the way to Tiryns where we hope to arrive on Sunday evening (and immediately descend on Scuola, our favorite Italian restaurant - even if it is in Greece, they have the best Caesar salad I've ever had in Europe).

Last year we had a monster Mercedes van from the Sonderforschungsbereich 'Our Way to Europe' of the Uni Cologne. It even had the motto, 'Our Way to Europe' painted on the side. Given the shaky nature of European relations at the time, we covered it up with our magnetic, Erdbebenstation Bensberg sign, hoping that wouldn't incite the Greek natives to come at us with pitchforks and torches quite as much. This year we're leaner and meaner since we're not taking the seismic refraction equipment with us. The passive seismic stations are still in Greece from last year where they've been recording local events for the past nine months, powered by battery and solar panels.

Our work this year will mainly be concentrated in Midea (we hope - we still haven't gotten the permission to work there - ah, Greek bureaucracy!), another fortified palace ruin on its own hill about 7 km northeast of Tiryns. (updated: we got the permission today - T-2 days. Do they read blogs there?)

The excitement (and the terror) of this year's field work is that we have purchased a differential GPS instrument that we'll be using for the first time in Tiryns/Midea and we'll be 'test driving' our new (also leaner and meaner) 3D laser scanner. Most field geophysicists are uniquely suited to these kind of experiments that I call, 'let's take a bunch of new equipment we've never tested before and go out in the field.' That's not because we're so smart, it's because we're flexible. We have to be. When you have cables and electronic devices and sensitive instruments, combined with weather extremes, precipitation and the unknown variables that always come into play during a measurement, something always goes wrong.

But it pays to be philosophical (translate: stock up on ouzo and Retsina and Mythos).

This is a big reason to look forward to the end of the working day at Tiryns.

 Our measurement plans this year include gravity measurements - this time with an ambitious plan to extend a profile from Tiryns to Midea - passive seismic (H/V), Transient electromagnetics (with a Greek colleague), and the laser scanning.

Dida from Tiryns

Käse from Anthemion House

Barbara from Midea

Our Greek colleagues from the animal world will be waiting for us as well. (Note to self: don't forget the dog and cat treats).






I'll be posting on our progress (with pictures) on the journey to Tiryns (it will be my first time to cross the Italian Alps) and, time permitting, on the measurements.