Especially when used in conjunction with other archaeological criteria, Tibetan literature is a precious indicator of the location and identity of archaic monuments. Bön (and to a lesser degree Buddhist) texts are an excellent and extensive source for mythic and quasi-historical accounts relating to places in Upper Tibet supposed to have been important centers of the ancient Zhang Zhung and Sumpa kingdoms. These texts provide biographical data about the lives of Zhang Zhung and Sumpa saints, including information regarding their residences and political dealings with local potentates and foreign enemies. These literary accounts are framed in both the prehistoric epoch and early historic period, but their historicity remains obstinately difficult to corroborate. For the most part, Bön literary sources postdate the eleventh century CE (centuries after the historical events they purport to chronicle) and are heavily colored with mythic and hagiographic content, significantly limiting their value as prosaic historical documents. This literature names geographic locations, some of which can be confidently correlated to the contemporary toponymic picture (places such as Mamik, Purang, Gugé, Dangra, Tago, Tisé, Namtso, Tanglha, etc.), while the identity of others has either not been established or only tentatively. As the chronology of Bön mythic and quasi-historical materials pertaining to Zhang Zhung and Sumpa is uncontrolled (by associative events such astronomical phenomena, natural disasters, cross-cultural references, calendrical lore, etc.), it limits their use as indexes of time, except in the broadest sense.

Moreover, Bön sources have been subjected to an ongoing process of textual revision, altering the portrayal of early historical events. This modification of contents expresses itself in two major ways: the idealization of past patterns of settlement and cultural achievement, and the reconfiguration of the archaic cultural heritage using the language and concepts of Buddhism. Nonetheless, Bön literature furnishes us with valuable contextual information on major centers of early settlement and their cultural and religious complexion. For one thing, a comparison of textual-based geographic lore related to Zhang Zhung with the patterns of archaic monumental distribution in Upper Tibet reveals a strong positive correlation.

The oral traditions surrounding the archaic monuments of Upper Tibet tend to contrast with these accounts connected to Buddhist monuments, in which piety and otherworldliness prevail. Since the domination of Lamaism in Upper Tibet, circa 1000 to 1250 CE, religious attitudes developed that altered perceptions of the earlier cultural heritage of the region. Generally speaking, this recasting of history led to the archaic past being viewed with a considerable sense of fear and denial. As Buddhism and systematized Bön gradually took hold in Upper Tibet, transforming its culture and ethos, the push to reinterpret history gained momentum in society. The major effect of this historical reformulation has been to make the ancient past increasingly resemble Lamaist thought and practice. In the contemporary socio-cultural setting, the archaic monumental wealth of Upper Tibet has been compressed into just four major themes. This thematic compression involves the reduction of the ancient cultural legacy into stereotypic narratives, which now stand as supposed factual representations of the past. This has led to the loss of much historical information once associated with the archaic archaeological assets in the oral tradition of Upper Tibet. The cognitive and affective forces enmeshed in this cultural transformation were not directed at highland archaeological sites alone, but came to express themselves in manifold social and political ways across the Tibetan world.

It is within these four legendary themes that clues pointing to the identification of archaic monuments must be sought: (1) the ancient Bön, (2) the Mön, (3) the Gesar epic, and (4) the pantheon of local spirits. These legendary and mythic attributions are generally applied to sites that do not fall under the architectural ambit of Lamaist culture. They function as convenient intellectual categories to relegate awkward bits of early heritage (which by their very physical presence cannot be simply brushed aside) to a safe and distant ideological realm. While the oral tradition provides associative evidence of early settlement, it is not well suited to the collection of archaeological facts concerning archaic monuments and rock art. The oral tradition, therefore, is best applied as a non-specific and broadly inclusive interpretive anthropological tool.

An excellent indicator of the archaic status of archaeological monuments in Upper Tibet is the presence of distinguishing features in substance and form. These physical properties reflect different architectural conceptions and modes of execution than those exhibited by familiar Lamaist monuments. Of special note are the various funerary pillars (menhirs) and necropoli of Upper Tibet. These types of monuments embody distinctive forms of abstraction and construction which do not appear to have been adopted by Lamaist adherents. A different religious ethos required an alternative assemblage of monuments: rather than large burial complexes, Buddhism and systematized Bön saw fit to cover the landscape with chöten (a type of shrine) and walls with inscribed plaques, which are of a different order of architectural magnitude. In the domain of residential monuments, great structural contrasts are seen between the all-stone corbelled edifices of early times and Bön and Buddhist buildings built with high walls and wooden rafters. Aside from the very different methods and materials used in construction, the former structures are small-chambered, windowless and semi-subterranean, while Lamaist halls and temples have larger rooms and frequently windows or skylights, and are set prominently above the ground.

The specific geographic setting of archaeological sites provides some clues to their cultural identity. Many archaic residential monuments were built at high elevation and in special environmental niches that have long since been abandoned. These sites were not the objects of sustained sedentary settlement in any way associated with the Lamaist cultural milieu of later times. A significant number of archaic sites are concentrated in defunct agricultural enclaves in far western Tibet, and on headlands and islands across the breadth of the Upper Tibetan lake belt. Archaic residential sites are also found on lofty, inherently defensible summits and ridges, or at the heads of valleys at elevations sometimes exceeding 5000m. Environmental degradation and changed cultural realities appear to be the motive forces behind the geographic shift from these specialized locations to the patterns of population distribution witnessed in more recent centuries. For the most part, the Lamaist religions chose lower-elevation basins and valleys for their major residential sites. Even when escarpments and mountain slopes were selected for the establishment of religious and political edifices, these are consistently located at a lower elevation than their archaic counterparts. Gang Tisé is an excellent case in point: all around this sacred mountain one must climb well above the existing Buddhist sites in order to reach those established in earlier times. The same patterns of settlement hold true for Dangra Yutso where the archaic cultural horizon looms over the contemporary Bön villages.

Comparative study of Upper Tibetan archaeological assets, with their counterparts in Central Tibet and Eastern Tibet, is another tool for ascertaining relative age and cultural affiliations. Unfortunately, very little reliable chronometric data has yet been assembled for archaic residential and ceremonial sites located in other regions of Tibet. Moreover, comprehensive archaeological surveys have yet to be launched outside Upper Tibet. The poorly organized archeological data compiled in other regions of the plateau impedes studies based on cross-referenced archaeological comparisons. As a result, the extent and nature of paleo-cultural affinities between Upper Tibet and Central Tibet and other regions of the plateau have not been adequately determined.

In Upper Tibet and Central Tibet, quadrate burial tumuli with inwardly sloping walls were built in the early historic period and most probably in the prehistoric epoch as well. However, the all-stone corbelled residential edifices and pillar monuments that define the Upper Tibetan paleo-cultural territory are not represented in Central Tibet. Kham and Amdo have varying assemblages of monuments (these are still not well catalogued). Nevertheless, the pastoral regions of Amdo were host to a rock art tradition that is thematically and stylistically related to that of Upper Tibet. The areal variability marking archaeological assets is acknowledged in the Tibetan historical tradition, which assigns prehistoric Central Tibet and Dokham to different proto-tribal or quintessential groupings. Central Tibet is recorded as being dominated by Bö, Kham by Minyak, and Amdo by Azha.

Cross-cultural Inner Asian study is a fecund methodological approach for the determination of the identity and chronology of Upper Tibetan archaeological assets. This method has proven best suited to the interregional comparison of funerary sites that possess substantial above-ground structural elevations. Archaic funerary pillars and slab wall structures are a case in point, where comparisons between the Upper Tibetan, Mongolian, Altaian and south Siberian types have borne good results. These basic monumental forms are dispersed throughout Inner Asia. As in other spheres where the technologies and cultural traditions of Inner Asia were disseminated widely, chronological and cultural parallels between the funerary monument traditions of Upper Tibet and adjoining regions are indicated. The comparative study of Inner Asian rock art is useful in delineating the amalgamative processes that brought Upper Tibet into functional and aesthetic congruity with its northern neighbors. The biggest drawback to cross-cultural analyses remains the general shortage of good chronological controls for sites in Upper Tibet. This will be remedied only when chronometric studies gain sufficient ground.

The aesthetic and technical analysis of art and artifacts is best used in conjunction with collateral archaeological data, but even alone it is a helpful method for estimating chronological values. The rock art record provides one of the best indexes of cultural evolution from the archaic to the Lamaist. The prehistoric Upper Tibetan rock art tableaux are rich in compositions that depict economic, environmental and cultural matters related to the way of life in the region. These petroglyphs and pictographs are largely unrelated to Buddhist-inspired art and design as they developed in Tibet. Rock art exhibiting archaic themes (such as hunting scenes, the isolated portrayal of wild animals, and iconic motifs) continued to be produced well into historic times. This suggests that there was a good deal of cultural continuity between the prehistoric and historic epochs in Upper Tibet. Nonetheless, analogous subject matter reveals different modes of manual execution and stylistic presentation, valuable evidence in any attempt at chronological differentiation. As compared to rock art made in the prehistoric epoch, the later variants exhibit their own set of production qualities and aesthetic refinement. Rock art of the historic epoch is either cruder or more polished. This inferred chronological progression is also discernable in other spheres of material culture. Copper alloy artifacts such as amulets, implements and weaponry possess aesthetic and technical features indicative of relative age and cultural affiliation as well.

In addition to these indirect means of assessing archaic cultural status, the radiometric and AMS assaying of organic remains recovered from sites constitute the direct approach to dating. The criteria outlined above are all dependent on inferring chronological information from evidence that does not intrinsically lend itself to scientific verification. For these criteria to be validated, the conclusions drawn from the cultural identity, appearance and location of monuments and rock art must ultimately stand the test of chronometric verification. Over the last four years, I have begun the process of independent corroboration of the suppositions set forth above. I am intent on presenting the identification of the corpus of archaic structural and aesthetic forms in Upper Tibet in a more objective and reproducible fashion. In pursuance of this goal, 20 samples have been submitted for radiometric and AMS analysis (derived from both residential and ceremonial sites). The recovery and archaeometric assaying of far more samples from many more sites is demanded to definitively chart the chronology (and other objective values) of the Upper Tibetan archeological assemblage. Archaeometric inquiry is also essential in weeding out those sites that may not have an archaic cultural horizon status. It is on a good footing that chronometric data assembled thus far have begun to corroborate the presumptions made concerning the temporal orientation of the sites surveyed.