History of Oakland County Michigan a narrative account of its historic progress, its people, its principal interests / compiled from the official records of the county, the newspapers and data of personal interviews, under the editorial supervision of Thaddeus D. Seeley.

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HISTORY OF OAKLAND COUNTY

IMMENSE DRIFT AND FORMATIONS BENEATH
Geologically considered, Oakland county belongs to the Drift' period.
Its water courses nowhere cut through the immense alluvial deposits of
sand, gravel and bowlders, to the rocks beneath. No minerals are known
to exist, except possibly in isolated sections mingled with the drift.
The rock formations underlying the drift all belong to the Carboniferous system. The coal measures are supposed to underlie a fraction
of the county northwest of Holly. Below them comes the Palma sandstone, which reaches a little further into the county; next lower, the Carboniferous limestone, with a still greater area; deeper still, the Michigan
salt group, which is supposed to underlie about two-fifths of the county;
then the Marshall sandstone group, believed to underlie the entire county;
and lastly, the Huron group, which extends beyond Oakland county into
adjoining districts.
Borings in the northwest corner of the county would penetrate all of
these formations, while in the southeast corner only the Huron group
will be found. The center of this geological basin would be near the line
between Gratiot and Midland counties, where the dip of the underlying
strata is probably the deepest; thence gradually rising toward the margin
of the basin. Fossils of various forms are found in the drift of Oakland
county.
The following information is condensed from the last report of the
Weather Bureau for the section known officially as Eastern Lower Michigan, being especially applicable to Oakland county: In this section there
are two high areas of land, the northern covering most of Otsego, Crawford and Roscommon counties. In the southern portion there is another
elevated area covering much of Jackson, Washtenaw and Hillsdale
counties; this elevation includes the sources of the Grand, Kalamazoo,
St. Joseph and Raisin rivers. A part of this elevated area extends northeastward into Oakland county and contains the headwaters of the Huron,
Rouge, and Clinton rivers. A comparatively low belt of land, extending from Saginaw bay to the lower valley of the Grand river, separates
these elevations. The greater part of the drainage is into Lake Huron,
Lake St. Clair or Lake Erie, although a portion finds its way to Lake
Michigan through the Manistee, Muskegon, and Grand rivers.
SOIL AND CLIMATE
The soil is varied in character. In the southern portion it is fertile
and well adapted to growing grains, grasses and fruits. In its original
state the land was covered with forests-of hard wood in the southern
portion and chiefly pine in the northern.
The yearly precipitation averages between thirty and thirty-five inches,
although there are limited areas where the yearly amount averages between twenty-five and thirty inches. It is well distributed throughout
the year, but is slightly greater during the spring and summer than during other seasons. In the northern portion the winter snowfall is heavy
and the ground remains covered during most of the winter, the accumulated depth of snow being often from two to three feet. In the south