While much of the proposed work for the 1988-89 season was of a preliminary nature the achievements were significant.

Hydrology

Three hydrometric sites were installed within the Miers Valley. A 120° "V" notch weir was established on the Adams Stream approximately 150 m downstream from the glacier front and a 60° "flume" was installed on the Miers, also approximately 150 m downstream from the snout. The third site, a 120° "V" notch weir, was installed on the lower Miers, approximately 300 m below the lake outlet. The two upper valley sites had backup Foxboro recorders installed as well as Geokon transducers linked to Campbell CR10 dataloggers to record stage height. The lower site was only monitored by a Geokon transducer and datalogger.

The weirs were installed in trenches approximately 7 m long (depending on the site characteristics), 400 mm deep, and a minimum of 300 mm wide. The upstream faces of the weirs were lined with PVC sheeting and backfilled with sand to prevent leakage. The wing-walls were extended with sand bagging, PVC sheeting, and hessian as required by the nature of the specific site. Leakage at all sites was less than 0.1% and it is believed that after the present winter, that is once the sites have refrozen, leakage will have stopped completely.

At each site special gauging reaches were constructed and over 20 gaugings were undertaken to develop a rating curve (calibration of stage height against discharge) for each weir. These rating curves would appear to be very accurate with little scatter about the best fit line.

In the coming season the transducers will be sealed in anti-freeze and a rubber membrane to prevent freezing and the resultant change in calibration offset. With regular maintenance this, however, was not a major problem last season.

The Water Resources Survey DSIR site in the Garwood valley was also maintained by K046 during the 1988-89 season.

Climate Stations

Two fully automated climate stations were established close to the hydrometric sites on the upper Miers and Adams Streams. These sites monitored air temperature, water temperature, humidity, incoming solar radiation, wind direction and speed, and soil temperature. All the sensors worked well, as did the data loggers which collected all the data, and a data record spanning 21/12/88 until 20/1/89 was recovered.

Software

Various pieces of software were written to calibrate the sensors and control the data loggers. All this software appears to have functioned well under the conditions found in the Miers valley.

Ablation Markers

Three rows of five ablation poles were installed on each of the Miers and Adams glaciers. The poles were placed in holes drilled 1.2 m into the glacier surface and were marked with flags for relocation. The position of each pole was determined from survey control sites adjacent to and above each glacier. Movement of the poles and the ice around them will be monitored in future seasons.

Ground Survey

Forty-four benchmarks were established by DOSLI during the period 1980-83 in the Marshall and Miers Valleys (L&S 37/99). Two of these stations were subsequently "doppler" fixed.

Seven of these benchmarks, BMM21-BMM27 were used during the 1988-89 season as a basis for control in the Upper Miers Valley. BMM21 is one of the doppler-fixed stations. BMM21 (Adjusted position) 163° 47′ 15.988′E 78° 05′47.086′S H = 164.080 m asl

Survey control

All seven DOSLI stations were observed and measured by K046. Five new stations were established to provide a triangulated control over the Upper Miers Valley. All lines to these 12 stations were observed and measured. One MWD lake level station was located and tied-into the above network.

Five new stations were established above and along the south-east side of the Adams Glacier to provide control stations to locate ablation poles on the glacier surface. All lines were observed and measured. Three similar stations were fixed above and along the south edge of the Miers Glacier.

Three stations were set-up to control each of the weir profiles and all lines to these stations were observed and measured. One station was set-up at the western end of Lake Miers to provide a control for levelling the lake surface. This level station was defined by repeated readings from BMM21. One station was set-up to establish the height of Keyhole Saddle. Nine stations were established to provide control for measuring the Adams glacier snout and five similar stations were established for measuring the Miers glacier snout.

Three profile lines were measured and observed through the swales among the moraine ridges and six stations were established to provide control for the lake ice level survey.

All the above stations were marked permanently and "cairned" for easy location. The locations of the stations on the rocky slopes above each glacier were described in detail and indicated by direction markers beside the glaciers.

Photogram metric control

Twenty-one photogrammetric height and planimetric control marks were established. Suitable features were observed and measured and graphically described to assist aerial photographic identification.

Stream bed profiles

At each of the three weirs, observations and measurements were made to establish stream bed profiles. The observations were made using the SET-4 EDM and a prism mounted on a hand-held range pole. Observations were taken at 50 cm intervals, reducing to 1 m over the near-level flood plane. In all 10 profiles were measured, each involving between 19 and 34 readings.

Slope profiles

Three profiles were measured using the conventional automatic level and levelling staff. The ends of the profiles were fixed by observation and measurement from the nearest benchmarks.

Ablation pole survey

Three rows of ablation poles were set into each of the glacier surfaces. Those on the Miers Glacier were fixed by observations from 2 control stations and measured from one. The Adams Glacier poles have been fixed by observations from 3 control stations. Bad weather conditions made distance measurements impossible.

Glacier snout survey

Nine control stations were established for the Adams Glacier and 56 marks, approximately 10 m apart, were set-up on the ice front. All 56 marks were observed from two stations with 18 observed from three stations for better control. At each mark the front of the icefall apron was observed and measured, as was the interface between the ice-fall apron and the vertical glacier front. The top of the glacier face was also observed from two stations. A similar procedure was carried out for the Miers Glacier.

Lake Ice level survey

Three lines were surveyed across the western portion of Lake Miers with eleven ice stations and two shore stations being observed and measured. At each lake station the features were measured and described.

Lake levels

Lake levels were measured at the eastern outlet of Lake Miers using the existing MWD control. At the western end of the lake a new levelling station was established and readings taken. Lake Salina was also levelled and profiled.

Assistance to DOSLI A member of K046 assisted K191 to measure and observe a number of benchmarks in the Garwood, Marshall and Miers Valleys to ensure that the necessary adjustments can be made to provide accurate survey and height control for these areas for the first time.

Peak observations

A number of observations were made of the surrounding peaks from the benchmark control in the valley.

Mapping

"Sketching-up" of the data was attempted in the Miers Valley as the surveys progressed. As yet, accurate plotting has not been undertaken except for a basic triangulation to establish enough control to fix the scale and planimetry of a map produced by photogrammetric plotting. This work provided the base for a geological map of the Miers Valley.