Late Precambrian Time Research Articles

Buried Pre-Cambrian Hills in Northeastern Barton County, Central Kansas

Six buried pre-Cambrian hills in the Kraft-Prusa, Beaver, and Bloomer oil fields are defined by 952 tests drilled within the 160 square miles mapped. These flat-topped hills were quartzite monadnocks on a Cambrian peneplain eroded across pre-Cambrian quartzite, schist, granite, syenite, granite-gneiss, and pegmatite. During the deposition of 220 feet of lower Cambro-Ordovician Arbuckle beds these monadnocks were islands. On their slopes sediments were deposited with 2° to 5° initial dips. They were buried under 340 feet of upper Cambro-Ordovician dolomites, under 40 feet of Ordovician Simpson shale, and probably also under 650 feet of younger pre-Pennsylvanian strata. Erosion culminating in an early Pennsylvanian peneplain exhumed five of the hills. Slight uplif followed. The paleo-outcrop belt of the truncated Cambro-Ordovician dolomites became a youthful karst plain pitted by sinkholes. Solution valleys to 1½ miles in width fringed each resurrected pre-Cambrian hill at the dolomite-quartzite contact. These solution valleys and sinkholes are partly filled with untransported leached residuum (chert, clay, sand) of the Cambro-Ordovician beds and with transported residuum-derived material deposited in them either as non-marine or marine Pennsylvanian conglomerate. In late Des Moines time the pre-Cambrian hills became diminishing islands in a transgressing sea. Limestones of the Missouri series were deposited on their summits. They are now buried under 3,300 feet of Pennsylvanian, Permian, and Cretaceous rocks. Oil is produced from Pennsylvan an limestones, shore-line sands of the Pennsylvanian marine conglomerate, Cambro-Ordovician dolomite, Cambro-Ordovician residual sand, and pre-Cambrian quartzite. The data obtained in this 4-year sample study were summarized graphically by plotting the height of the hills above the average ground surface, or their depth of burial below it, as ordinates and geologic times as abscissas. The resulting curve summarizes quantitatively the vertical movements experienced by the six quartzite hills from late pre-Cambrian time to the present.

Buried Pre-Cambrian Hills in Northeastern Barton County, Central Kansas

Six buried pre-Cambrian hills in the Kraft-Prusa, Beaver, and Bloomer oil fields are defined by 952 tests drilled within the 160 square miles mapped. These flat-topped hills were quartzite monadnocks on a Cambrian peneplain eroded across pre-Cambrian quartzite, schist, granite, syenite, granite-gneiss, and pegmatite. During the deposition of 220 feet of lower Cambro-Ordovician Arbuckle beds these monadnocks were islands. On their slopes sediments were deposited with 2° to 5° initial dips. They were buried under 340 feet of upper Cambro-Ordovician dolomites, under 40 feet of Ordovician Simpson shale, and probably also under 650 feet of younger pre-Pennsylvanian strata. Erosion culminating in an early Pennsylvanian peneplain exhumed five of the hills. Slight uplif followed. The paleo-outcrop belt of the truncated Cambro-Ordovician dolomites became a youthful karst plain pitted by sinkholes. Solution valleys to 1½ miles in width fringed each resurrected pre-Cambrian hill at the dolomite-quartzite contact. These solution valleys and sinkholes are partly filled with untransported leached residuum (chert, clay, sand) of the Cambro-Ordovician beds and with transported residuum-derived material deposited in them either as non-marine or marine Pennsylvanian conglomerate. In late Des Moines time the pre-Cambrian hills became diminishing islands in a transgressing sea. Limestones of the Missouri series were deposited on their summits. They are now buried under 3,300 feet of Pennsylvanian, Permian, and Cretaceous rocks. Oil is produced from Pennsylvan an limestones, shore-line sands of the Pennsylvanian marine conglomerate, Cambro-Ordovician dolomite, Cambro-Ordovician residual sand, and pre-Cambrian quartzite. The data obtained in this 4-year sample study were summarized graphically by plotting the height of the hills above the average ground surface, or their depth of burial below it, as ordinates and geologic times as abscissas. The resulting curve summarizes quantitatively the vertical movements experienced by the six quartzite hills from late pre-Cambrian time to the present.

Paleozoic paleogeography of Arizona

Research Article| September 01, 1942 Paleozoic paleogeography of Arizona ALEXANDER STOYANOW ALEXANDER STOYANOW Search for other works by this author on: GSW Google Scholar GSA Bulletin (1942) 53 (9): 1255–1282. https://doi.org/10.1130/GSAB-53-1255 Article history received: 17 Nov 1941 first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation ALEXANDER STOYANOW; Paleozoic paleogeography of Arizona. GSA Bulletin 1942;; 53 (9): 1255–1282. doi: https://doi.org/10.1130/GSAB-53-1255 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract In Arizona two major areas of deposition separated by Mazatzal Land had already been established by late pre-Cambrian time. The first Paleozoic transgression from the northwest, starting possibly late in the Early Cambrian and depositing the Tapeats sandstone, reached central Arizona. The southern limit of the Bright Angel shale and the overlap of the Muav limestone on the Tapeats indicate subsequent movements northward and southward in early Middle Cambrian time before the final withdrawal of the Cambrian sea from northern Arizona. In southeastern Arizona, likewise, only the earliest phase of the Cambrian transgression reached the central part of Mazatzal Land; the northwestern boundaries of the late Middle Cambrian Troy, Santa Catalina, Cochise, and the Upper Cambrian Abrigo formation are all successively regressive southeastward. Ordovician strata are known in Arizona only in the areas near New Mexico. Silurian and early Devonian deposits are present only near the extreme peripheral margins of Mazatzal Land beyond the limits of the State. Central-western Arizona was a positive element during the Ordovician, Silurian, and both the Early and Middle Devonian. The overlapping late Devonian transgression, also initiated from the northwest and southeast, deposited clastics around the central part of Mazatzal Land and was succeeded by deeper sea conditions in Mississippian time. The southeastern trough was the deeper of the two basins throughout the Late Paleozoic and is regarded as an arm of the Ouachita seaway. Following the retreat of seas from most of Arizona in the Late Mississippian a marked early Pennsylvanian transgression was introduced from the southeast and limited on the northwest by Mazatzal Land. Grading of the Manzano gypsiferous series and fossiliferous limestones into the Supai northward and distribution of Kaibab faunas establish the relation of the southeastern trough to the northern area of Permian shallow marine and continental deposition. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not currently have access to this article.

Pre-Pennsylvanian Stratigraphy of Nebraska

Sioux quartzite, granite, and schistose metamorphic rocks have been recognized in the pre-Cambrian. The present irregularities, the basins and highs, on the pre-Cambrian surface are the result of erosion and a long structural history. In general succeedingly younger rocks rest unconformably by overlap against the pre-Cambrian highs. The principal erosional and structural highs are: the mountains, the Cambridge anticline, the Chadron dome, and the Sioux Falls area. Basins, or saddle-like depressions, occur on the pre-Cambrian surface between the highs. The largest of these trends from southeast to northwest across the central part of Nebraska. The history of each ridge or high is more or less individualistic, but it seems certain that the structural fr mework of Nebraska came into existence in late pre-Cambrian time and has dominated the structural and depositional history of the state ever since. Every Paleozoic system below the Pennsylvanian is represented by identifiable rocks in the subsurface section of Nebraska, and all are present at least east of the buried Nemaha ridge. The exact subsurface distribution of each of the Paleozoic systems is not yet known with certainty. Apparently all formations are the same and are continuous with the pre-Pennsylvanian rocks of Iowa. The Cambrian and Ordovician rocks of the southern part of the state are also quite similar to correlative formations in Oklahoma. The fact that most of the deep test wells so far drilled in the state have been located on structural or on monadnock-like pre-Cambrian highs has precluded the discovery of many pre-Pennsylvanian Paleozoic rocks, which do occur in the basins. This has led to the misconception that Nebraska was not invaded by all of the Paleozoic inundations.

The Lower Huronian Ice Age

When geologists slowly became convinced of the reality of the Pleistocene glacial period it was held to be a unique catastrophe belonging to the later history of a cooling world, something without precedent in earlier geological epochs. Then, reluctantly and with astonishment, a Permo-Carboniferous glacial period, even more tremendous than that of the Pleistocene, was admitted as proved. Later still, an extensive ice age in early Cambrian or late pre-Cambrian times has been demonstrated, carrying back continental glaciers to the beginning of known life in the world. For a number of years it has been my belief that a still earlier glacial period was the cause of the widespread basal conglomerate of the Lower Huronian; and last year, when a few scratched stones were obtained from this conglomerate at the silver-mining region of Cobalt, it seemed worth while to show that a Lower Huronian ice age was highly probable.' During the past summer fresh material has been collected in the Cobalt region, including some well-preserved soled bowlders with ice-smoothed surfaces and well-marked striae, removing all doubt of the glacial origin of the conglomerate; and it is proposed to present here the evidence for this most ancient of known ice ages.