Reliving a Memory is a work based on the 1950 diary of George Blakslee.

"January 19, 1950.... Travelled south to Ain es Sufr where we attempted to get up over scarp where sand ridge dropped off scarp. We made it, but it was necessary to move a few rocks. It was necessary to winch sedan last few feet. Traveled east along back slope of Tuwaiq into valley between two Irqs, couldn’t go any further so returned. Got stuck in soft sand –– necessary to winch out with Dodge."

"January 20, 1950.... Got stuck in soft sand on north side of Irq. Have found that south side of Irq sand is harder. Apparently the presence of grass makes no difference on north side."

"March 11, 1950.... Carried the traverse over some pretty rough country and then headed west for Ain Ajaliya. The country was covered with small Kw hills with large quartzite rocks. (boulders) We made our tie with the astro at the Ain, but everything that could happen, happened to the sedan. The front spring shackle broke, the spring broke as well. The exhaust manifold came loose. The air vent to the radiator broke - we just threw that away. The engine side panels broke under the fenders. The tie rod was bent beyond repair and the drag link was also bent beyond repair......The possibility of the tie rod going entirely led us finally to give it up and limp back into camp."

Early in 1950, construction of the railroad linking Dammam on the Persian Gulf and Riyadh, the capital, had begun. The only other railroad in Saudi Arabia, the narrow-gauge line linking Damascus to Medina had been sabotaged by Lawrence and his Hashemite force during the First World War and never repaired. Paved highways existed only in the Hejaz, but Aramco had oiled some frequently traveled routes between its facilities and had paved the streets of Dhahran and the roads to Khobar and Dammam. Elsewhere tracks and trails connected oases and towns, but in only a few places had any effort been made to improve them. Off these tracks, as mentioned in the chapter, 'The Weather and Us,' terrain controlled the speed of wheeled vehicles, and often prescribed their route. Almost unhindered by these considerations, camels plodded in their hundreds, head to tail, at four miles an hour between major oases, avoiding high dunes and boulder-strewn areas. By the fifties, trucks had begun to follow their trails and encroach on their loads of dates and other agricultural produce.

The entries in the diary quoted above describe some of the hindrances that George and Gier encountered. But on those days they were either trying to get from one place to another by the most direct route, i.e. a straight line, or exploring possible passages between mountains of sand, far from the trails made by caravans going from one inhabited site to another. Even these traveled routes offered difficulties for wheeled vehicles, sand-tired or not, when they traversed the Dahana or the nefuds. But vast areas in central Arabia are gravel plains on which vegetation is sparse, and large tracts of playa-like terrain were and are ideal for wheeled traffic.

Mobile Equipment The automotive equipment used by this field party in 1950 was two Dodge Power Wagons, (one with stake body and power winch, the other with box body and power hoist) and a 1949 Ford sedan equipped with an oversize radiator and fan, a two-way radio powered by the 12-volt battery that sparked the car’s ignition, and sand tires. The rubber on the sedan was a special order 913 wide tread sand tire with a drop center rim that was fully inflated at nine pounds pressure.
Photographs by George Blakslee

That is why George and Gier were able to cover 280 miles in one day over mainly trackless country. (February 27) The logistics of maintaining a two-man camp with a support group of twenty for six months 400 miles from Dhahran was routine. The Exploration Department had had fifteen years of experience in desert operations. Methods had changed after 1934 when the first geologists landed at Jubail and hired camels to carry fragile, square-sided five-gallon tins of gasoline far into the interior to supply their conventionally equipped vehicles. In 1950 the cans were carried to the field by truck, but the thin-walled galvanized tins with soldered joints were just as likely to leak or rupture on jolting trucks as on plodding camels. Tins had two advantages over the sturdier 55 gallon drums that had replaced them in some areas: One man could load and unload them, and their content was not contaminated with oil, dirt, or water, a common failing of the drums.

Airplane Tires The Dodges were fitted with DC-3 airplane tires. Their use made these heavy-duty pickups almost unstoppable in loose sand, at the cost of replacing a broken axle at about every 2500 miles. The large Kenworth semi was sent out only once with a load of aviation gasoline for the first of two planned aerial reconnaissances.

Fuel for vehicles at work was carried in the leaky five-gallon tins stacked in the follow-up Power Wagon. Five-gallon jerry cans were usually in reserve in the trunk of the sedan. Blowing sand sometimes caused stoppages in the fuel lines after refueling.

To keep the vehicles rolling, a mechanic, Abdul Wahhab, came to the field with a variety of spare and replacement parts for all the vehicles. Fortunately he proved to be fully competent and a hard worker.

Abdul Wahab Abdul Wahhab

As may be inferred from the diary entry for 11 March, (above) he had his hands full most of the time, going out to repair or tow in an abandoned vehicle, and checking the roadability of the sedan after each day’s operations. But for several weeks he was away, so the diary has many notations regarding car and truck repair by the geologists. Typical entries when Abdul Wahhab was in camp:

"March 27, 1950....Trucks didn’t show so we drove back looking for them. Found them towing Dodge which had burned out bearings. The clutch plate in stake body is burned too."

"March 28, 1950....I occasionally walked over and watched Abdul Wahhab and once helped to pull the engine out of the dodge."

"April 10, 1950....At a point some 7 kilometers east of Khasm El Barda we broke right rear axle about 10:30 a.m. Picked up notes and returned to camp in dodge follow-up car. Abdul Wahhab went out, made repair and brought sedan in about 4:00 p.m."

"April 18, 1950....On the road south of Laila Gier hit a bump so hard that it washed out the rear spring completely. We transferred field book and plane table sheets to dodge and returned to camp. Had lunch and Abdul Wahhab went out to repair sedan."

"April 21, 1950....Spent day in camp while Abdul Wahhab made repairs to the sedan, replacing radiator, putting in new front spring and shock links and new drag link."

Competency is precious where replacement is difficult. The drivers for the Dodges were not as reliable as Abdul Wahhab. One went off in a Dodge after a gazelle and was overtaken only when Gier drove at speeds exceeding 80 miles an hour to overtake him. The culprit was fired on the spot, so that when camp moved thereafter George had to drive one of the Power Wagons. Other drivers were unskilled, reckless or careless, and all were prone to arrive after a reasonable travel time had expired.

Stuck Stuck

When working in sand dunes and sand-covered area the sedans often ran into difficulties from which they were rescued by the Power Wagon. Along with the mechanical difficulties and sand storms the geologists were sometimes unable to do field work. They used this enforced leisure to complete and collate the information already in hand.

Aramco Plane Aramco Plane

Nevertheless, the mapping program went forward more or less as scheduled, aided by two aerial reconnaissance flights and the assistance of two or three other more senior geologists who for nearly a month worked with George and Gier as discrete teams, although sometimes exchanging partners. Additional transportation (two airplane-tired Dodges and two sedans) was available during this period.

"February 2, 1950....Today we split into two parties and worked independently to accomplish more. I went with Krug and Gier went with RAB......I really learned a lot today working with Krug — he’s a darned good teacher He manages to put things in one syllable so you can understand...."

"February 14, 1950....Today, RAB, BB, and I went planetabling to the east for strike and dip.... Krug and Gier went just south of east about 70 kilos"

Food and replacement parts for vehicles were sent from Dhahran in the stake-body Power Wagon once a month. All were ordered by radio well in advance of the truck’s departure, for the round trip took at least five days. Daily communication was on a schedule and an emergency call could be made at any time, for Dhahran receivers were always open. But contact was not always possible.



"March 11, 1950....This morning up early –– had breakfast, set up car antennae. Tried making radio contact but Bud said our signal was too weak, so we gave up."

"March 15, 1959....Up by radio contact — weren’t able to make radio contact."

"March 16, 1950....This morning again we were unable to make radio contact."

"March 17, 1950....Tried our charged batteries with the radio — found we couldn’t put out a signal so gave up."

"March 31, 1950....Had breakfast and as we were making radio contact, the radio failed. Didn’t bother to try new contact."


Radio Transceiver A powerful battery-powered transceiver was installed in the geologists’ tent. It can be seen in the background. Gier was told that he could send messages for a thousand miles when reception was good. The aerial was a length of copper wire tailored to the wave-length of the transmission. It ran from the tent to the top of a 60-foot steel pole made up of ten-foot joints. The batteries were charged by the gasoline-powered Onan generator that provided lighting to the geologists’ and mess tents. It was often down for repair.
Radio Then, and always at the spike camps, the transceiver mounted in the sedan was used to make daily contact with the Dhahran station, HZA. The aerial for this car-installed set was 60 feet of 10-foot lengths of copper tubing screwed together and mounted vertically in a holder attached to the sedan.

Routine reports to Dhahran were scheduled for about 7 A.M. every morning as one in a prescribed sequence of field stations including three field parties and three structure-drill camps. On most days this was the only contact, and when the base camp transmitter malfunctioned there was usually none. However, in emergencies a call could be made at any time, day or night with either radio. George talked to his wife, Kathy, on several occasions. The telephone at their apartment in Dhahran could be patched into the circuit.

Spike Camp Spike Camp

"January 24, 1950....Decided to stay around camp and work up some odd details. Tried HZA, contact at 10:15 a.m. Dhahran time. Made contact but Kathleen not home — was I disappointed!"

"February 1, 1950....Made radio contact with HZA and talked with my wife for 10 to 15 minutes. It certainly was a morale builder and I was so glad to hear that Warren-Leigh has started to stand up."

"February 25, 1950....About 11:45 a.m. was able to get through to HZA and made connection with Kathy. We talked for about 10 minutes and then it was over and out. Sure was fun talking with my wife."

"April 5, 10:30 a.m. when I called Kathy. It was so nice to hear her voice again. Warren Leigh’s great day has arrived. since Kathy informed me that he now stands up in his playpen. Unfortunately our talk was cut short since we ran into a radio schedule."

"April 28, 1950....Called Kathy on radio at 9:30 p.m., but contact was poor — sure nice to hear her voice again though."

The geologists overcame the barrier of language by learning and using a set of orders in Arabic. They were supplemented by a vigorous use of sign language and example. Too, some of the staff had learned the meaning of certain English phrases and were pleased to recite them in more or less appropriate circumstances. Several English words had been taken into current usage in Arabic, albeit with some alterations in pronunciation or original meaning: Benzine=gasoline; bencil=pencil; spanna=wrench

The Tools We Used


"January 18, 1950....Plan on working Geol. meas. sections. Worked up three sections in ink."

"January 22, 1950....Started out chasing red shale member down Tuwaiq scarp. Decided to measure section at Khashm er Rumda. Spent a few hours climbing and measuring to Tres and JTtm contact."

"January 24, 1950....Made another check on speedometer calibration on 2 kilometer chain made yesterday."

"January 26, 1950....RAB, Henry and myself went out fossil hunting - had some success and measured a section."

"January 27, 1950....RAB and I started out planetabling outcrops in the immediate area, including for the most part JTtm and JTtm crests on the back slope. Dick held rod and worked stratigraphy laterally, picking up known outcrop and bed and following through to establish dip on a through point intercept. I operated the instruments: plane table, alidade and barometer."

"February 4, 1950....Coming up to the point from which we intended working Gier and I shot angles, ran rod on beds and traversed the rest of the day, while RAB and Krug measured sections."

"February 9, 1950....Krug and Gier headed toward the SE and RAB, Burt and myself headed N.75E. The heading remained about the same throughout our traverse. We were able to get about 100 kilometers into the interior of the Rub al Khali from our camp. We traversed out and ran a double barometer traverse back to camp."

"February 14, 1950....Today RAB, BB and I went plane tabling to the east for strike and dip. I acted as instrument man and RAB and BB rodded."

"February 23, 1950....Made preparations after arriving at camp to make an astronomical observation. As we set up our equipment, Gier found that our split second chronograph was broken."

A large part of the geologists' work was to determine the thickness, sequence, and attitude of the succession of sedimentary strata in an area near the southwestern limit of the Aramco concession. A portion of the stratigraphic column there had been studied cursorily by previous workers, but in fact much of the southern portion of the Tuwaiq region was terra incognita geologically and to a great extent unexplored topographically. Too, the work would provide a better understanding of the problems of access to this vast essentially trackless region, including the forbidding fastnesses of the western Rub' al Khali.

Brunton Compass Brunton Compass
Photograph by Nestor John Sander

For mapping they used the Brunton compass, the Wild theodolite, a stadia rod, and either an odometer-barometer (altimeter) or a plane table-alidade traverse tied to signals.

Stradia Rod

These points of known location and elevation were marked by metal posts set in cement topped with metal flags painted black. They had been determined previously by second order triangulation surveys, but when necessary the geologists established a secondary point of reference using their own ‘star shots’ for location and traverses to provide an elevation. Elevations were generally determined using two barometers traversing from a signal, but on occasion were found through measurements of angles with theodolite or alidade, converted at once to a vertical equivalent The plane table and alidade were used often to tie locations and measured sections into a traverse.

Geological information was recorded in detail, using a hand-lens to determine the lithology of the sequence of rocks observed. The thickness of each unit was measured in feet and inches. The sections so compiled were plotted on tenth-inch cross-section paper accompanied by a written description. The strike (longitudinal trend) and dip (amount of tilt from the horizontal) of the strata were difficult to measure with the small Brunton compass because of the low dip to the east of all strata studied. But the Brunton was used to determine the azimuth of traverses and maintain a straight course.

Theodolite Theodolite and Brunton

To determine the dip of these nearly horizontal strata either an alidade or a theodolite was used in conjunction with a stadia rod  to obtain an accurate measure of a bed’s inclination - its deviation from the horizontal - an angle called "dip." (It was determined through reading the largest angle of slope among a number of rod positions taken along a presumed strike line.) The azimuth of a line in a horizontal plane at right angles (normal) to the dip is the strike of that bed.

Owing to the low eastward dip of the rock units, the long, west-facing cliffs of the Tuwaiq erosional cuesta and its outliers were a precious mine of information. Changes in the lithology and thickness of strata exposed along its length could be recorded and their faunas studied in detail. East of the escarpment and the old river channels that cut through it, the sequence was more difficult to study and the dunes of the Rub al Khali permitted only glimpses of the rocks under them.

Petrified Logs Excursions far into this sand sea were attempted only twice. On one of these sallies, petrified logs were seen at a site where the ubiquitous sand was almost absent. They are clear evidence that the climate changed from one of at least moderate rainfall to the driest of deserts. The log is at least 200 million years old.

Two aerial reconnaisances flew over the great dune chains of this ‘Empty Quarter’ both traversing it from north to south and return. On the second of these flights George, securely, tethered, stood at the open hatch and snapped more than fifty pictures.

But at that time a more usual and immediately accessible and useful method of studying and mapping topography and plotting the location of measured thicknesses of geologic strata was the odometer-altimeter traverse. Trimetragon aerial photographs helped in planning these traverses, but distortions of scale toward their edges made these photos less than ideal guides and references, although always useful for planning suitable routes of access.

Progress had made easy what was a major preoccupation of the geologist in the fifties: accurate positioning and mapping of the geological data obtained. Although all of the instruments discussed are still used in field work, the geographic location and elevation above sea-level of a point or a series of points is now a matter of minutes because of the existence of a satellite-controlled global positioning system. The drudgery involved sixty years ago in the accurate measurement of distance has been eliminated, and vertical and oblique photos by satellite make mapping more exact.