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During the Late Bronze and Iran Ages, Ziyaret Tepe was an important Assyrian urbancenter, serving for a while in the Late Assyrian period as the regional capital of the borderprovince, when the site was known as Tushhan (see Roaf in Matney et aL. 2002).The o<strong>ve</strong>rall goals of the 2002 field season were: (1) to continue work in the Ap eration E step-trench started in 2000 and, in particular, to excavate both Middle Assyrianperiod remains near the top of the sequence and early second millennium Be andearlier le<strong>ve</strong>ls at the base of the Operation E step trench; (2) to document the architecturalsequence of the Operation A public building and the nature of the underlying depositsbeneath the building's foundation platform; (3) to expand excavation of the OperationG Late Assyrian structure with the e<strong>ve</strong>ntual goal of reco<strong>ve</strong>ring a complete planof the building; (4) to explore possible Roman-period remains in the lower town previouslyreco<strong>ve</strong>red via surface sur<strong>ve</strong>y in Operation J in the westernmost portion of the 10wer town; (5) to continue earlier subsurface magnetic field gradiometry sur<strong>ve</strong>y at ZiyaretTepe initiated during the 1998 and 1999 seasons with an ultimate goal of mappingthe entire Late Assyrian city; (6) to begin a detailed geomorphological description andreconstruction of the paleoenviranment of the Upper Tigris region. This report detailsour progress towards the last two of these goals. The results of the excavations notedabo<strong>ve</strong> under the first four goals are reported in the Kazı Sonuçları Toplantısı series andthe preliminary reports noted abo<strong>ve</strong>.Geophysical Sur<strong>ve</strong>y: Magnetic Field Gradiometry Sur<strong>ve</strong>yMagnetic field gradiometry sur<strong>ve</strong>y (hereatter ngradiometryn) is a non-invasi<strong>ve</strong>geophysical sur<strong>ve</strong>y technique which maps subsurface features using sophisticatedcomputer modeling software to chart minute fluctuations in the strength and directionof the earth's magnetic field. The measurement of the ambient magnetic field of theearth is taken using a hand-held gradiometer, which incorporates two separate andhighly sensiti<strong>ve</strong> magnetometers in a simple perpendicular array (l.e., during operation,the sensors are aligned one on top of the other in relation to the le<strong>ve</strong>l of the earth's surface).Measurements are taken on a measured grid corresponding to the o<strong>ve</strong>rall sitegrid, con<strong>ve</strong>rted to digital values and stored in a data collector attached to the hand-heldunit. Variations in the readings of the earth's ambient magnetic field (measured in nanoTesias)are caused by any of a number of shallow subsurface features including: underlyinggeological formations, highly ferraus artifacts (e.g., iran artifacts) and in situ firedsoils which contain iron particles (e.g., hearths, kilns). While these artifacts and featurescause a relati<strong>ve</strong>ly strong anomalies in the earth's magnetic field (on the order of100-200nT against the earth's ambient field strength of 20,000+nT), much weaker signalson the order of 0.1 to 1OnT are easily recordable with standard gradiometers andotten reflect weak signals of great significance for archaeologists. An example of a weakersignal would be differences between iron-poor Iimestone wall foundations andiron-rich collapse originating from the decay of mud-brick made from iran-bearing soils.Geophysical sur<strong>ve</strong>y using gradiometry methods started at Ziyaret Tepe in 1998.The placement of excavation trenches at Ziyaret Tepe during the 2000-2002 excavationseasons has largely been guided by the results of subsurface magnetic field gradiometrysur<strong>ve</strong>ys. Two initial field seasons of subsurface magnetic field gradiometry werecarried out in 1998 and 1999 at Ziyaret Tepe (Matneyand Somers 1999; MatneyandBauer 2000). The purpose of those sur<strong>ve</strong>ys was to test the efficacy of using magneticsur<strong>ve</strong>y techniques at Ziyaret Tepe. Favorable results were obtained, as reported previously,and it was decided that a total sur<strong>ve</strong>y of the site would be conducted, starting in2002 and continuing for se<strong>ve</strong>ral seasons. In 2002, our geophysics team conducted sur<strong>ve</strong>yin two portions of the site: the western high mound and the western lower town(Fig. 1). These areas were chosen for se<strong>ve</strong>ral reasons. On the high mound, extensi<strong>ve</strong>excavations on the eastern edge of the site in Operations A and E ha<strong>ve</strong> begun to clarifythe nature of remains in that area. In contrast, the western side of the high mound98