The principal oil-bearing horizons in any locality are comparatively few, and it is ordinarily easy to determine by stratigraphic methods the presence or absence of a favorable geologic horizon.
In searching for minerals of sedimentary origin, the explorer will use stratigraphic methods in following definite sedimentary horizons.
Comparatively recent advances in this phase of exploration work have been in the more detailed application of stratigraphicmethods to the iron formation.
The success of certain paleontologists andstratigraphic specialists in oil exploration is an evidence of this situation.
This is coming to play an increasingly large part in geologic work, and is essential to the interpretation of many mineral deposits, particularly those in which stratigraphic and physiographic questions are involved.
Many residual and transported soils are to be recognized in the geologic column; in fact a large number of the sedimentary rocks ordinarily dealt with in stratigraphic geology are really transported soils.
Such groupings are especially useful in the case of minerals which are closely related to certain stratigraphic horizons, such as coal, oil, and iron.
It is scarcely possible to summarize briefly all of the structural and stratigraphic methods used in locating the ore bodies.
Still further, the primary deposition of Clinton iron ores in many parts of the Mississippi Valley and eastward to the Appalachians took place in stratigraphic horizons not far removed from the horizons of lead and zinc deposition.
The stratigraphic horizons favorable to their accumulation are generally recognized.
The stratigraphic position of the bone concentration in relation to the total Nacimiento section exposed in Kutz Canyon has not been determined.
Indeed, the stratigraphicposition of the Angels Peak pocket with a considerable thickness of Torrejonian strata beneath it, tends to argue against such a view.
The absence of the mesonychids might, but probably should not, be explained as a result of stratigraphic differences.
The stratigraphic relations of the two formations are shown in Fig.
We speak of the lost intervals represented by stratigraphic breaks or unconformities and commonly emphasize our ignorance concerning them.
That two phases of the Topanga Culture exist is shown by stratigraphic evidence in the Tank Site with supporting evidence in the adjacent LAn-2 characterizing a Phase II period.
Since clear-cut stratigraphic evidence is lacking it is difficult to assign other classes of artifacts as being definitely associated with any one specific phase of the Topanga Culture.
This assumption is further backed by stratigraphicevidence provided by projectile points (table 4).
The eight typable points represent too small a series, and the deposit is too shallow to show any stratigraphic differences within the site.
Through lack of clear-cut stratigraphic evidence, all other artifacts described for the Tank Site will have to be considered either as late Phase I or early Phase II.
What we have here is fault that has caused a stratigraphic trap.
Many of my customers have located oil-containing faults and stratigraphic traps with my detector where all other instruments had failed.
Stratigraphic section showing the archaeologic layers of the great grotto of Castillo.
As to its stratigraphic relations, the type station of Solutre exhibits lower and middle Solutrean above Aurignacian hearths and deposits; that of Placard, Charente, shows the middle and upper Solutrean overlaid by a Magdalenian layer.
Stratigraphic section at Palo Duro Canyon with Geologic Time-scale for reference.
For this reason detailed discussion of stratigraphic units will be confined to those rocks that can be seen within the boundaries of the monument or closely adjacent to it (Fig.
We would like to cite particularly Doctors Steven Oriel and Joshua Tracy of the United States Geological Survey, whose studies have clarified the stratigraphic relationships of the sediments involved.
Age and stratigraphic relations of the Fowkes Formation, Eocene, of southwestern Wyoming and northeastern Utah.
A substantial break or gap in the geologic or stratigraphic record.
The Mudstone and Sandstone tongues are not dated by means of fossils but the stratigraphicrelationships indicate an early Eocene age.
It is interesting to note that the Lower Member is intermediate not only in stratigraphic position but also in color and composition between the underlying Evanston Formation and overlying Main Body of the Wasatch Formation.
He mapped the rocks in certain areas of the basin in an attempt to bring a semblance of order to Hayden's (1869) broad stratigraphic descriptions.
Intertonguing relationship of latest Cretaceous and Tertiary stratigraphic units of Fossil Basin.
Revision ofstratigraphic nomenclature of the Green River Formation of Wyoming.
At the base of the stratigraphicsection are rocks of Precambrian age.
Reported from numerous Pleistocene deposits of all stratigraphic levels, especially from the Great Plains, where common today.
He placed the stratigraphic position of the fauna as definitely Upper Pleistocene, probably deposited in both Illinoian glaciation and during the Sangamon interglacial.
The Saw Rock Canyon fauna and its stratigraphic significance.
Numerous records, mostly isolated teeth, from nearly all stratigraphic levels of the Pleistocene (for details, see account of fossil record).
The relationships within the subfamily Entoptychinae are modified after Wood (1936), and the temporal range of the Miocene geomyids have been adjusted to agree with current stratigraphic correlations.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "stratigraphic" in a variety of sentences. We hope that you will now be able to make sentences using this word.
