1. Introduction

Alpha Archaeology Pty Ltd (Alpha) is working with the Archaeology and Anthropoloical Society of

Victoria (AASV) to carry out a geophysical survey of the Viewbank Homestead, Heidleberg (Error:

Reference source not found). The aim of this survey is to assess the extent of the boundary for the

homestead tip site. An EM survey was performed to measure the resistivity of the ground as well as the

induced current.

1.1.Location and Description of Study Area

The study area is located in Heidleberg, Victoria (Banyule City) and is currently a heritage listed area. The

area is used as a recreation park and the plenty river trail crosscuts the park. The homestead is

positioned on the junction between the Plenty River and the Yarra River.

On the property the homestead has been identified, the footings of the house, garden terraces and

some plants still survive. It is possible that terraced areas to the south and east of the house are

locations for cellars, stables and servants quarters. Rubbish tips located to the east of the homestead

have also been identified. The purpose of this paper will be to identify the size, number and boundaries

for the rubbish tips.

Global Positioning System coordinates defining the boundaries of the study area are given in Table 1

Table 1: GPS coordinates defining the study area for the Viewbank tip

Corner of the study area Easting Northing

NE 332160.9 5820498

SW 332112.3 5820477

NW 332110.8 5820492

SE 332164.1 5820469

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Map 1: Location of Study Area

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2. BackgroundThe Viewbank homestead is a respectable residence. The Viewbank residence was originally settled by

Edward Willis in 1839. The final owner of the Viewbank Homestead was Dr. Robert Martin, who

undertook extensive renovations and alterations to the original house. When Dr. Martin passed away

there was no heir to the property. In the 1920s it was sold to the Bartram family, where the house was

demolished. The property is now owned by Parks Victoria (Smith 2001).

Robert Martin was borne in Skye, England in 1978. His early life before moving to Australia is not well

known. In 1839 he migrated to Australia where he owned a number of stations and properties before

moving to the Viewbank residence. It is unknown when he lived at any of his four properties. Martin’s

wealth makes the Viewbank residence an interesting insight into the lifestyle of the upper class during

the late 19th century in Melbourne. (Kenyon & Billis, 1974).

There have been extensive studies completed on the Homestead, and much of the architecture of the

building has been mapped (). The area was geophysically mapped in 1996 by Heison et al, using a

variety of techniques including GPR and resistivity methods. This survey covered the whole area

identifying the main tip site which will be covered in this survey.

Previous studies of the homestead have been completed. Sarah Hayes catalogued in excess of 20,000

artifacts from the area. However there has been a lack of suitable reports which have been produced.

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Figure 1: Floor plan: Viewbank Homestead

3. Geophysical methods

To identify the bounds of the tip area a geophysical survey was conducted. Using an EM31 geophysical

device it was possible to measure the conductivity of the ground as well as detect magnetic objects. The

device creates circular eddy current loops which induces a magnetic field which is proportional to the

conductivity of the ground. The conductivity is determined by looking at the quadrant-phase

component. The inphase component is more sensitive to metallic object and can be used to determine

the presence of buried metal objects. The conductivity of the ground can be used to identify variations

in the composition of the underlying ground. EM surveys have been used in the environmental industry

to identify the boundaries of decommissioned tips.

The results were collected in a grid pattern with lines every four meters from the center and readings

taken every two meters. The area near the known dig site had line spacing of two meter. Where

anomalies were identified during the initial survey smaller lines were followed to refine these data

points. This pattern was chosen to gain the highest spatial resolution possible within the time available

for completing the survey. All data points are marked with a small cross on both Figure 2 and Figure 3.

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4. Assessment of Geophysical results

Figure 2: Inphase component (metallic object detection) for Viewbank homestead

The inphase components indicate that there is a significant anomaly around the known tip site. At some

points the values changed depending on the orientation of the boom. At these points it is highly likely

that there are pieces of metal rubbish such as horse shoes, flower tins and other cans. The magnetic

object detection is a very good way to identify some of the waste which would have been produced by

the household. These measurements will not identify nonmetallic waste such as china, burnt objects and

any waste produced by renovations or modifications to the house.

At some points within and near to the tip site there were local anomalies where the inphase component

was different depending on the orientation. These locations have been mapped on Figure 2 as red

crosses. To be classified as a significant change the anomaly must have varied by ±.3 which is

approximately 10% of the lower values recorded. These local anomalies are most likely influenced by

the geometry of the objects which are buried. However it is also possible that they are not related to the

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Martin settlement and are a result of the Bartram farm as there is a fenceline running very close to the

known tip site.

Generally the conductivity values are a good indicator for the boundaries of modern tip sites. However

the result of the conductivity survey (Figure 3) does not show any anomalies over the known tip site.

There are no variances between the conductivity of the tip site and the surrounding ground. However it

is possible that the low in conductivity seen near the known tip and to the east of the tip is influenced by

the burning of rubbish which was commonplace during this period.

Figure 3: Conductivity readings from the Viewbank homestead area

As the results from the conductivity survey did not indicate a viable tip site the inphase component was

primarily used to identify a target location. The main anomaly is identified and a suggested dig site is

highlighted in Figure 4. The area mapped out is approximately 4mx15m. This is consistent with the

reports from the previous geophysical survey.

Figure 4: Suggested dig site

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5. Conclusions and Recommendations

Due to the strong geophysical response seen from the inphase component it is recommended that the

area showing a distinct boundary be investigated. If more resolution is required prior to excavation it

would be appropriate to use a GPR survey to further define the geometry of the tip site. A GPR survey

would also allow the depth to be constrained. Due to time and funding constraints a GPR survey was

not conducted, the EM31 survey providing adequate information for the community dig to occur.

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