GEOLOGICAL SURVEY OF MICHIGAN. For this object I have zealously worked. How far I have succeeded in the effort the reader may judge; and I shall feel well satisfied if he finds the picture I give worth UPPER PENINSULA attentive study, without having it surrounded by a 1869-1873 borrowed glistening frame, composed of a collection of ACCOMPANIED BY AN items from almost every branch of human knowledge. ATLAS OF MAPS. Very respectfully yours, C. ROMINGER. VOL. I. PART III. PALÆOZOIC ROCKS. INTRODUCTION. BY DR. C. ROMINGER BY the Legislative Assembly of 1871, the continuation of a geological survey of the State of Michigan was determined upon, in such a manner as to divide the work PUBLISHED BY AUTHORITY OF THE LEGISLATURE OF into three districts, each of which was to be investigated MICHIGAN. independently by different parties. UNDER THE DIRECTION OF THE BOARD OF GEOLOGICAL SURVEY. The third district, intrusted to me, comprises the Lower Peninsula, and the eastern half of the Upper Peninsula, NEW YORK or that portion which Is not included in the iron and JULIUS BIEN copper regions. Its surface rock is exclusively 1873 composed of members of the palæozoic series; while In Entered according to Act of Congress, in the year 1873, by the other two, older crystalline and metamorphic rocks GOVERNOR J. J. BAGLEY, prevail. for the State of Michigan, in the Office of the Librarian of Congress, at Washington. On the Lower Peninsula only a partial reconnoissance TO THE HONORABLE BOARD OF GEOLOGICAL SURVEY OF tour has been made through Little Traverse Bay region. THE STATE OF MICHIGAN: The principal part of the time has been spent in the Gentlemen—I have the honor to lay before you the Investigation of the Upper Peninsula, of which the Board results of my investigations in the geology of the eastern of the Survey desired to have a complete report at the portion of the Upper Peninsula of Michigan, which work end of this year. was placed in my hands by the Honorable Board during the past two years. GEOGRAPHICAL LIMITS AND All the facts reported upon, including the chemical analysis of quite a number of rock specimens, are SURFACE CONFIGURATION OF THE derived from my own personal labors and observations. DISTRICT. I have avoided, as much as practicable, expanding the bulk of the report; and have paid no more than the THE Upper Peninsula of Michigan comprises an area of absolutely necessary attention to other branches of about 16,000 square miles, excluding the several islands natural history, which, although very interesting, are not belonging to the State, which add to this sum 300 square strictly comprehended under the word geology, and to miles more. which I could not make any personal contributions of To the north it is bounded by the waters of Lake value. A great portion of this material would have been Superior, to the south by the Lakes Huron and Michigan; a mere copy of the published records of others; and I the east end is bounded by the river St. Mary, which cuts think the public does not care so much for a compilation, from the main body three larger islands—Sugar island, as for an actual increase of our knowledge by carefully St. Joseph's island, and Drummond island; the first and made observations, elucidating unknown or imperfectly the last of which belong to the State; St. Joseph is understood features in the construction of the earth's Canadian land. crust. The western, or more accurately speaking, the southwestern boundary line between the Upper Peninsula of Michigan and Wisconsin territory, is given by the bed of the Menominee river, flowing into Green bay of Lake Michigan, and by the Montreal river emptying into Lake Superior, which bounds the remaining western portion of the Peninsula. Volume I, Part III – Page 1 of 39 The so defined land lies between the 45th and 49th GENERAL PRELIMINARY REMARKS degrees of northern latitude, and 83° 45' and 90° 93' of longitude west of Greenwich. ON GEOLOGY, An air line drawn from the mouth of the Menominee river The object of the subsequent report is to give an explicit to the mouth of the Montreal river is about 175 miles description of the above indicated portion of our State, long; from the mouth of Montreal river to the north end of regarding its soil, the different rock-beds composing its Keewenaw point, a similar line measures 150 miles; and surface, and the various minerals associated with them. a line drawn from Marquette to the mouth of the It intends to explain, as far as science will allow, the Menominee river amounts to about 100 miles. process by which all these materials were formed, and in what relation they stand to each other. It seeks to point These three lines inclose the Iron and Copper Districts; out the different uses to which all of them are applicable only the smaller portion of this area is overlaid by strata in the economy of the human race, and means to aid in of the palæozoic series, which on the remaining eastern the understanding of the great unalterable law, which portion of the Peninsula, exclusively compose the governed creation in the past, as well as it does in the surface. present time. This remaining portion extends about 175 miles from In order to accomplish this in a plain and comprehensive west to east, and is about 50 miles in width from north to way, I find it necessary to disregard those readers, who south. are already well informed, and for the benefit of those The surface elevation of the two western districts who are not so well informed, to preface these remarks exceeds considerably that of the eastern district; the by a short exposition of some elementary geological highest points of the eastern portion do not go beyond principles. 400 feet, while in the two others some mountains attain Every person is naturally inclined to inquire into the a height of 800 feet, and a few a height of 1,400 feet nature of things surrounding him ; and one of the most above the lake level. obvious objects for such inquiry are the different rocks, The character of these western districts is irregularly strewn in fragments over the surface, or buried in the mountainous. The eastern end of the Peninsula ground in massive blocks, or in well stratified ledges. represents an undulating high plateau, sinking in gradual Without being geologists, we observe granites and other descent towards the south, and more rapidly falling off rocks of crystalline structure, we notice slates, shales, towards the north. Its watershed lies much nearer to the sandstones, limestones, coalbeds, iron ores and other northern than to the southern margin, and consequently, mineral substances, under various conditions. the rivers emptying into Lake Superior are generally We find, sometimes, a variety of these rocks small in comparison with those entering Lake Huron and indiscriminately mixed, in rounded water-worn Lake Michigan. The headwaters of these rivers take fragments; at other times they exhibit a certain regularity their origin from numerous lakes and marshes dispersed in their position, and succeed each other in a fixed order, over the plateau. None of them are navigable for their layers piled up, one upon another, like the leaves of anything larger than a canoe, on account of the a book. frequency of rapids and cascades; particularly those of the north side, where almost every creek precipitates its Usually, the stratified rock-beds are in horizontal waters over mural exposures of the Lake Superior position, but frequently also, we find them inclined, or sandstones. Nevertheless, these rivers and creeks are standing vertical, or even reversed or twisted, in all of high economical importance, by affording in the spring imaginable curves; ripple marks present themselves on season, when the waters are high, ample power for the hardened stone-faces, as plain as those formed floating the logs from the interior down to the numerous under our eyes by the play of waves on the shallow saw-mill establishments sprung up at the mouth of sand-banks of our lakes and rivers; unmistakable shells, almost every larger watercourse, whose branches reach corals, and other animal or vegetable remains are back into the pine lands. imbedded in the stone-mass, sometimes in such profusion as to constitute the principal body of the rock. The whole eastern Peninsula is an unbroken forest, All these and many other geognostical facts, present having, except the lumbermen, no other inhabitants than themselves to our daily observation, and there are few some solitary trappers in the winter time; while, during who are not deeply interested by them, and seek for the summer season, the fishermen take their temporary explanations how all this originated, and how and when abode along the shore. Only a few of them have things assumed their present condition and form. It is squatted down, and remain there all the year. Besides the science of Geology which attempts to answer these these there are a few migratory Indians. questions. With the increased accumulation of geognostical facts, we become more and more enabled to bring isolated observations into a system; to see the connections in which one phenomenon stands with another, and to Volume I, Part III – Page 2 of 39 deduce and recognize therefrom the rules and laws rocks; but this is not the case always; we frequently find which are guiding the terrestrial development. the sedimentary beds in contiguity with the crystalline rocks, only slightly altered, while on the other hand, Much has been achieved by these efforts to disclose the sometimes a high degree of metamorphism is observed earth's history, but much more yet has to be learned, in a series of strata, too far remote from the focus of heat before we can have a clear comprehension of all the to allow a transmission of any high degree to it, to such a successive changes which our globe has undergone, distance.