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Midcontinent Rift System

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for petroleum. Oil identified as Precambrian has been found seeping out of the Nonesuch Shale in the White Pine mine in Michigan. A few deep wells were drilled to explore for oil and gas in rift rocks as far southwest as Kansas. No oil and gas were found, but the explorations did make some deep
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and creation of a sea. The Midcontinent Rift appears to have progressed almost to the point where the ocean intruded. But after about 15–22 million years the rift failed. The Midcontinent Rift is the deepest closed or healed rift yet discovered; no known deeper rift ever failed to become an ocean.
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to the east which in part overlaps the timing of the rift development. Later compressive forces from the Grenville Orogeny likely played a major role in the rift's failure and closure. Had the rifting process continued, the eventual result would have been sundering of the North American
1091: 1294:. United States Geological Survey Mineral Resources Program, Eastern Mineral and Environmental Resources Science Center. A detailed and well-illustrated resource focusing on the mineral resources of the Midcontinent Rift and its geologic history. 1092:
National Research Council; Division on Engineering and Physical Sciences; Commission on Physical Sciences, Mathematics, and Applications; Geophysics Research Board, Assembly of Mathematical and Physical Sciences, Geophysics Study Committee (1980).
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Geological map of North America showing the Midcontinent Rift in white, here labeled Keweenawan Rift. Lake Superior now occupies the apex of the rift; the section to its north marked "SUPERIOR" is the
189:. The hotspot domed the rocks of the Lake Superior area. Voluminous basaltic lava flows erupted from the central axis of the rift, similar to the present-day rifting underway in the 378:
times, reactivated in the 1840s and continued for more than a century. Some low-grade copper and nickel deposits, among the largest in the world, also exist in the
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that are exposed in its northern reaches, but buried beneath later sedimentary formations along most of its western and eastern arms. Those arms meet at
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Ojakangas, R. W.; Morey, G. B.; Green, J. C. (1 June 2001). "The Mesoproterozoic Midcontinent Rift System, Lake Superior Region, USA".
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Lake Superior occupies a basin created by the rift. Near the present lake, rocks produced by the rift can be seen on the surface of
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formation in the Keweenawan Rift contains enough organic carbon (greater than 0.5%) to be considered a potential
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A slightly older but possibly related geologic feature is the 2,700,000 km (1,000,000 sq mi)
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defines the northern arc of the rift. From the lake, the rift's eastern arm trends south to central lower
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Iowa magnetic anomaly map showing the rift curving from the north center to the southwest of the state.
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The rift system may have been the result of extensional forces behind the continental collision of the
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Results of the Middle Proterozoic Midcontinent rift frontier play along Lake Superior's south shore
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The southwest and southeast extensions represent two arms of the triple junction while a third
1276:"The Potential for Geologic Hydrogen for Next-Generation Energy | U.S. Geological Survey" 1094: 351:
also drilled a 17,851 ft (5,441 m) dry hole that penetrated rift sediments in Iowa.
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could be found or produced in the Mid-continental Rift System at scale for a renewable
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J.A. Seglund, "Midcontinent rift continues to show promise as petroleum prospect,"
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of Superior in Minnesota and Ontario. Similar rocks are exposed as far south as
1589: 1555: 1412: 1372: 1303: 475: 394: 379: 355: 327: 171: 19: 778:. University of Wisconsin-Milwaukee. Archived from the original on 6 July 2008 1605: 1072:"Gravity and Aeromagnetic Anomaly Maps of the Southern Peninsula of Michigan" 858:. U.S. Department of Energy, Office of Scientific and Technical Information. 495: 367: 152: 148: 68: 40: 1223: 749:. Illus. Dan Breedy. Minneapolis, Minnesota: University of Minnesota Press. 1550: 1540: 1466: 1456: 1407: 564: 209: 156: 64: 1314: 386:, these deposits have attracted renewed interest from resource companies. 1251:"PolyMet's copper-nickel mine rekindles decades-old environmental debate" 479: 456: 363: 331: 324: 300: 249: 238: 111:. The western arm runs from Lake Superior southwest through portions of 72: 56: 958:. Iowa Department of Natural Resources Geological Survey. Archived from 907:
A Superior Swath: Proterozoic Geology of the North American Midcontinent
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of the Upper Peninsula of Michigan, northwest Wisconsin, and on the
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rock samples available. These include two "dry holes" drilled by
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deposits in Keweenawan-age rocks associated with the rift. A
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to a depth of 4,966 ft (1,514 m) in 1992. In 1987
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Geological rift in the center of the North American continent
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Schneider, D. A.; Holm, D. K.; Chandler, V. (Fall 2006).
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Pages displaying short descriptions of redirect targets
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Iowa Geological Survey Resource Information Fact Sheet
1173:, Oil & Gas Journal, 18 September 1995, pp. 80–82. 1133: 1299:"New Insights into North America’s Midcontinent Rift" 1224:"Mineral potential and geology of the Duluth Complex" 904: 583:
Pages displaying wikidata descriptions as a fallback
813: 35:is a 2,000 km (1,200 mi) long geological 1292:"Mineral Deposits of the Midcontinent Rift System" 776:Field Trips, Northern Wisconsin and Upper Michigan 594: 155:(black). The buff area on the north margin is the 983:"Interstate State Park, A Brief Geologic History" 851:Reeves, T. K.; Carroll, Herbert B. (April 1999). 745:Ojakangas, Richard W.; Charles L. Matsch (1982). 551: – Landform in Thunder Bay district, Ontario 163:The rock formations created by the rift included 1603: 1202:"FAQ: Everything you need to know about PolyMet" 796:: CS1 maint: bot: original URL status unknown ( 1221: 682: 643:"Middle Proterozoic and The Mid-continent Rift" 1047:Daniels, David L.; Snyder, Stephen L. (1991). 1330: 850: 692:Annual Review of Earth and Planetary Sciences 1134:Kucks, Robert P.; Hill, Patricia L. (2005). 1119:: CS1 maint: multiple names: authors list ( 1070:Hinze, W.; Kellogg, D.; Merritt, D. (1971). 683:Van Schmus, W. R.; Hinze, W. J. (May 1985). 47:. It formed when the continent's core, the 1344: 1337: 1323: 1228:Mineral Potential and Geology of Minnesota 1012: 1010: 1136:"Iowa magnetic and gravity maps and data" 1099:. National Academies Press. p. 180. 1040: 956:"Introduction to the Midcontinental Rift" 954:Anderson, Raymond R. (25 November 2014). 719: 339:: a 7,238 ft (2,206 m) well in 953: 947: 933:"The story of Isle Royale National Park" 898: 846: 844: 740: 738: 678: 676: 674: 672: 670: 668: 314: 232: 142: 138: 18: 1617:Geologic provinces of the United States 1016: 1007: 926: 924: 382:north of the lake. Once thought to be 1604: 1248: 1199: 1063: 809: 807: 1318: 1001:Interstate State Park Management Plan 930: 841: 770:Kean, William F. (24 November 2000). 735: 665: 637: 635: 600: 405:and the hydrogen could be extracted. 1309:https://doi.org/10.1029/2016EO056659 1215: 921: 769: 310: 1081:. Michigan State Geological Survey. 980: 974: 804: 763: 712:10.1146/annurev.ea.13.050185.002021 572: – Volcanic activity in Canada 13: 632: 291:in Canada, which extends from the 204:extends north into Ontario as the 51:, began to split apart during the 14: 1703: 1687:Mesoproterozoic rifts and grabens 1285: 1028:. United States Geological Survey 389: 276:rock increases gravity locally), 228: 63:, leaving behind thick layers of 1583: 522: 506: 487: 467: 448: 430: 415: 289:Mackenzie Large Igneous Province 71:, which is contained within the 59:, about 1.1 billion years ago. 1268: 1249:Kraker, Dan (5 December 2013). 1242: 1200:Kraker, Dan (2 December 2013). 1193: 1184:Exploring the Midcontinent Rift 1176: 1163: 1150: 1127: 1085: 1051:. Minnesota Geological Survey. 1026:National Oil and Gas Assessment 993: 941:United States Geological Survey 909:. American Geophysical Union. 685:"The Midcontinent Rift System" 147:Rift rocks are exposed in the 43:and south-central part of the 1: 1418:Ethiopian and Yemen Highlands 1222:Jira, Mark; David Southwick. 834:10.1016/S0037-0738(01)00085-9 588: 579:Volcanology of Eastern Canada 343:in 1987 and 1988, and one in 647:Minnesota's Rocks and Waters 237:Volcanic strata protrude at 7: 931:Huber, Norman King (1975). 542: 208:. This failed arm includes 10: 1708: 1297:Stein, Seth et al. (2016) 1079:Report of Investigation 14 1017:Palacas, James G. (1995). 455:Eroded volcanic strata at 408: 345:Bayfield County, Wisconsin 1579: 1352: 1019:"Superior Province (051)" 662:(Powerpoint presentation) 601:Stein, Carol (May 2018). 1138:. U.S. Geological Survey 772:"Keweenawan Rift System" 560:Mamainse Point Formation 41:North American continent 29:Midcontinent Rift System 23:Midcontinent Rift System 1692:Large igneous provinces 1346:Large igneous provinces 1160:, 15 May 1989, p.55-58. 651:Winona State University 1362:Northeast Georgia Rise 1255:Minnesota Public Radio 981:Jol, Harry M. (2006). 886:Cite journal requires 372:copper mining industry 341:Alger County, Michigan 320: 245: 160: 24: 1096:Continental Tectonics 570:Volcanology of Canada 537:, Minnesota-Wisconsin 535:Interstate State Park 513:Saint Louis River in 318: 266:Saint Paul, Minnesota 236: 146: 139:Formation and failure 49:North American craton 39:in the center of the 22: 1682:Geology of Wisconsin 1677:Geology of Tennessee 1652:Geology of Minnesota 1501:Mackenzie dike swarm 989:on 15 December 2012. 917:. Abstract #T42A-06. 820:. 141–142: 421–442. 515:Jay Cooke State Park 498:and Shovel Point in 305:Northwestern Ontario 278:aeromagnetic surveys 131:, and possibly into 91:, and possibly into 45:North American Plate 1667:Geology of Oklahoma 1657:Geology of Nebraska 1647:Geology of Michigan 1642:Geology of Kentucky 1546:Paraná and Etendeka 1433:Franklin dike swarm 1423:Equatorial Atlantic 1378:Brazilian Highlands 1158:Oil and Gas Journal 915:2006AGUFM.T42A..06S 826:2001SedG..141..421O 817:Sedimentary Geology 747:Minnesota's Geology 704:1985AREPS..13..345V 619:10.1130/GSATG357A.1 1672:Geology of Ontario 1627:Geology of Indiana 1622:Geology of Alabama 1590:Geology portal 1169:Albert B. Dickas, 555:Geology of Ontario 384:uneconomic to mine 321: 254:Keweenaw Peninsula 246: 243:Keweenaw Peninsula 161: 25: 1637:Geology of Kansas 1597: 1596: 1106:978-0-309-02928-5 962:on 4 January 2019 756:978-0-8166-0953-6 374:was developed in 311:Natural resources 270:gravity anomalies 217:Grenville Orogeny 206:Nipigon Embayment 195:East African Rift 185:which produced a 1699: 1588: 1587: 1503: 1496: 1494:Coppermine River 1469: 1447: 1435: 1388:Central Atlantic 1368: 1339: 1332: 1325: 1316: 1315: 1280: 1279: 1272: 1266: 1265: 1263: 1261: 1246: 1240: 1239: 1237: 1235: 1219: 1213: 1212: 1210: 1208: 1197: 1191: 1180: 1174: 1167: 1161: 1154: 1148: 1147: 1145: 1143: 1131: 1125: 1124: 1118: 1110: 1089: 1083: 1082: 1076: 1067: 1061: 1060: 1044: 1038: 1037: 1035: 1033: 1023: 1014: 1005: 997: 991: 990: 978: 972: 971: 969: 967: 951: 945: 944: 928: 919: 918: 902: 896: 895: 889: 884: 882: 874: 872: 870: 857: 848: 839: 837: 811: 802: 801: 795: 787: 785: 783: 767: 761: 760: 742: 733: 732: 730: 728: 723: 689: 680: 663: 661: 659: 657: 639: 630: 629: 627: 625: 598: 584: 575: 549:Coldwell Complex 526: 510: 491: 471: 452: 434: 419: 403:produce hydrogen 399:hydrogen economy 127:to northeastern 1707: 1706: 1702: 1701: 1700: 1698: 1697: 1696: 1662:Geology of Ohio 1632:Geology of Iowa 1602: 1601: 1598: 1593: 1582: 1575: 1499: 1492: 1465: 1443: 1431: 1398:Circum-Superior 1393:Central Iapetus 1360: 1348: 1343: 1288: 1283: 1274: 1273: 1269: 1259: 1257: 1247: 1243: 1233: 1231: 1220: 1216: 1206: 1204: 1198: 1194: 1181: 1177: 1168: 1164: 1155: 1151: 1141: 1139: 1132: 1128: 1112: 1111: 1107: 1090: 1086: 1074: 1068: 1064: 1045: 1041: 1031: 1029: 1021: 1015: 1008: 998: 994: 979: 975: 965: 963: 952: 948: 929: 922: 903: 899: 887: 885: 876: 875: 868: 866: 855: 849: 842: 812: 805: 789: 788: 781: 779: 768: 764: 757: 743: 736: 726: 724: 687: 681: 666: 655: 653: 641: 640: 633: 623: 621: 599: 595: 591: 582: 573: 545: 538: 531:St. Croix River 527: 518: 511: 502: 492: 483: 472: 463: 453: 444: 435: 426: 424:Superior Craton 420: 411: 392: 366:contains major 360:Upper Peninsula 313: 262:Interstate Park 231: 191:Afar Depression 187:triple junction 172:intrusive rocks 141: 61:The rift failed 53:Mesoproterozoic 33:Keweenawan Rift 17: 12: 11: 5: 1705: 1695: 1694: 1689: 1684: 1679: 1674: 1669: 1664: 1659: 1654: 1649: 1644: 1639: 1634: 1629: 1624: 1619: 1614: 1595: 1594: 1580: 1577: 1576: 1574: 1573: 1568: 1563: 1558: 1553: 1548: 1543: 1538: 1525: 1520: 1518:North Atlantic 1515: 1510: 1505: 1497: 1486: 1481: 1476: 1471: 1459: 1454: 1449: 1445:Sverdrup Basin 1437: 1425: 1420: 1415: 1410: 1405: 1403:Columbia River 1400: 1395: 1390: 1385: 1380: 1375: 1370: 1353: 1350: 1349: 1342: 1341: 1334: 1327: 1319: 1313: 1312: 1295: 1287: 1286:External links 1284: 1282: 1281: 1267: 1241: 1214: 1192: 1175: 1162: 1149: 1126: 1105: 1084: 1062: 1039: 1006: 992: 973: 946: 920: 897: 888:|journal= 840: 803: 762: 755: 734: 698:(1): 345–383. 664: 631: 592: 590: 587: 586: 585: 576: 567: 562: 557: 552: 544: 541: 540: 539: 529:Dalles of the 528: 521: 519: 512: 505: 503: 493: 486: 484: 473: 466: 464: 454: 447: 445: 438:Sleeping Giant 436: 429: 427: 421: 414: 410: 407: 395:White hydrogen 391: 390:White hydrogen 388: 380:Duluth Complex 356:Copper Country 328:Nonesuch Shale 312: 309: 230: 229:The rift today 227: 140: 137: 75:. 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Retrieved 610: 606: 596: 565:Nemaha Ridge 517:in Minnesota 393: 376:Precolumbian 353: 322: 299:to near the 286: 247: 214: 210:Lake Nipigon 199: 162: 157:Lake Nipigon 149:buff-colored 32: 28: 26: 1528:Ontong Java 1440:High Arctic 1260:10 December 1207:10 December 1142:3 September 1057:11299/60081 613:(5): 4–10. 480:Thunder Bay 457:Isle Royale 364:Isle Royale 332:source rock 325:Proterozoic 301:Great Lakes 272:(its dense 258:North Shore 250:Isle Royale 239:Isle Royale 212:, Ontario. 77:north shore 73:rift valley 57:Precambrian 55:era of the 1612:Aulacogens 1606:Categories 1513:Mistassini 1508:Matachewan 1484:Long Range 1479:Keweenawan 838:(Abstract) 589:References 494:Cliffs at 202:failed arm 197:system. 1561:Skagerrak 1536:Hikurangi 1489:Mackenzie 1462:Kerguelen 1383:Caribbean 1366:Maud Rise 1115:cite book 607:GSA Today 500:Minnesota 482:, Ontario 117:Minnesota 113:Wisconsin 105:Tennessee 85:Minnesota 31:(MRS) or 1571:Winagami 1556:Siberian 1532:Manihiki 1474:Marathon 1428:Franklin 1413:Emeishan 1234:13 April 792:cite web 721:1808/104 656:13 April 543:See also 474:A mafic 461:Michigan 274:basaltic 252:and the 241:and the 133:Oklahoma 125:Nebraska 101:Kentucky 89:Michigan 1551:Shatsky 1523:Ongeluk 1452:Iceland 1357:Agulhas 1190:2006-2. 1032:10 June 911:Bibcode 869:10 June 822:Bibcode 727:10 June 700:Bibcode 442:Ontario 409:Gallery 358:in the 297:Nunavut 282:seismic 193:of the 183:hotspot 169:granite 109:Alabama 93:Indiana 81:Ontario 1566:Ungava 1541:Panjal 1408:Deccan 1373:Azores 1307:, 97, 1103:  966:27 May 782:8 June 753:  293:Arctic 284:data. 280:, and 222:craton 176:basalt 165:gabbro 129:Kansas 123:, and 107:, and 1075:(PDF) 1022:(PDF) 856:(PDF) 688:(PDF) 624:1 May 349:Amoco 337:Amoco 264:near 179:lavas 159:area. 1262:2013 1236:2008 1209:2013 1144:2009 1121:link 1101:ISBN 1034:2007 968:2016 892:help 871:2007 798:link 784:2007 751:ISBN 729:2007 658:2008 626:2018 476:sill 362:and 323:The 174:and 167:and 121:Iowa 97:Ohio 83:and 37:rift 27:The 1304:Eos 1301:. 1186:". 1053:hdl 860:doi 830:doi 716:hdl 708:doi 615:doi 533:at 478:at 459:in 440:in 303:in 295:in 79:in 1608:: 1364:, 1253:. 1226:. 1117:}} 1113:{{ 1077:. 1024:. 1009:^ 939:. 935:. 923:^ 883:: 881:}} 877:{{ 843:^ 828:. 806:^ 794:}} 790:{{ 774:. 737:^ 714:. 706:. 696:13 694:. 690:. 667:^ 649:. 645:. 634:^ 611:28 609:. 605:. 307:. 135:. 119:, 115:, 103:, 99:, 95:, 1534:- 1530:- 1504:) 1491:( 1470:) 1464:( 1448:) 1442:( 1436:) 1430:( 1369:) 1359:( 1338:e 1331:t 1324:v 1311:. 1278:. 1264:. 1238:. 1211:. 1182:" 1146:. 1123:) 1109:. 1059:. 1055:: 1036:. 970:. 943:. 913:: 894:) 890:( 873:. 862:: 836:. 832:: 824:: 800:) 786:. 759:. 731:. 718:: 710:: 702:: 660:. 628:. 617::

Index


rift
North American continent
North American Plate
North American craton
Mesoproterozoic
Precambrian
The rift failed
igneous rock
Lake Superior
rift valley
north shore
Ontario
Minnesota
Michigan
Indiana
Ohio
Kentucky
Tennessee
Alabama
Wisconsin
Minnesota
Iowa
Nebraska
Kansas
Oklahoma

buff-colored
Lake Superior
Lake Nipigon

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