抄録
The author discusses and stresses the applicability of heavy mineral composition as a useful marker to characterize or identify the individual turbidite sandstone bodies based on the detailed and systematic heavy mineral analysis of many Neogene turbidite sandstone bodies in the Neogene Niigata oil basin, central Japan. Main results are summarized as follows:
1) Each turbidite sandstone body, corresponding to a formation or member, yields the same or common characteristics of the heavy mineral composition, that is, each body can be represented by the specific, but generalized heavy mineral composition. However, the different sandstone bodies are often composed of different heavy mineral composition.
2) Based on the combination of specific heavy minerals, heavy mineral composition of these sandstones are classified into several types. Each turbidite sandstone body is represented by one type or closely related two types.
3) The heavy mineral analysis of turbidite sandstones often yields a very important key or a new information in disclosing their sedimentary process, especially when its results are combined with results by sedimentological analysis such as facies analysis, paleocurrent analysis and so on.
4) As a conclusion, the analysis is very valuable not only as a conventional tool to estimate the provenance, but also as a strong measure to estimate the original relationship of several sandstone bodies neighboring each other, to disclose their sedimentary process with other sedimentary data, and to predict the three-dimensional extents of turbidite sandstone bodies both on the surface and subsurface by using samples from outcrops and from boring cores or cuttings.
