Guaymas Basin High-resolution Diatom and Silicoflagellate Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!! NAME OF DATA SET: Guaymas Basin High-resolution Diatom and Silicoflagellate Data LAST UPDATE: 7/2005 (Original receipt by WDC Paleo) CONTRIBUTOR: John A. Barron, U.S. Geological Survey IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2005-054 SUGGESTED DATA CITATION: Barron, J.A., et al. 2005. Guaymas Basin High-resolution Diatom and Silicoflagellate Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2005-054. NOAA/NGDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Barron, J.A., D. Bukry, and W.E. Dean. 2005. Paleoceanographic history of the Guaymas Basin, Gulf of California, during the past 15,000 years based on diatoms, silicoflagellates, and biogenic sediments. Marine Micropaleontology. Volume 56 (3-4):81-102. ADDITIONAL REFERENCES: Barron, J.A., D. Bukry, and J.L. Bischoff. 2004. High resolution paleoceanography of the Guaymas Basin, Gulf of California, during the past 15,000 years. Marine Micropaleontology, v.50 (2004) pp. 185-207. Keigwin, L.D., 2002. Late Pleistocene–Holocene paleoceanography and ventilation of the Gulf of California. J. Oceanogr. 58, 421– 432. Pride, C., R. Thunell, D. Sigman, L. Keigwin, M. Altabet, and E. Tappa. 1999. Nitrogen isotopic variations in the Gulf of California since the last deglaciation: response to global climate change. Paleoceanography 14 (3), 397– 409. ABSTRACT (Barron et al. 2005): High-resolution records of calcium carbonate, biogenic opal, diatoms, and silicoflagellates from western Guaymas Basin gravity core GGC55 and piston core JPC56 and eastern Guaymas Basin DSDP Site 480 reveal a complex paleoceanographic history of the central Gulf of California during the past 15,000 years. Prior to ~6.2 ka, the eastern and western Guaymas Basin proxy records were remarkably similar. After conditions similar to those of today during the Bølling–Allerod, the Younger Dryas (YD) saw a major drop in diatom production, coincident with increased calcium carbonate and tropical microfossils suggestive of El Nino-like conditions. Biosiliceous productivity began increasing during the latter part of the YD, but it was only during the earliest Holocene (11.6 to 11.0 ka) that conditions similar to those of the Bølling–Allerod returned to the central Gulf. Between around 11.0 and 6.2 ka, tropical diatoms and silicoflagellates were virtually absent from the central Gulf, as relatively cooler and fresher surface waters resembling those of the modern northern Gulf were present in the central Gulf. Beginning at about 6.2 ka, tropical diatoms and silicoflagellates began increasing in the central Gulf, and coccoliths returned to western Gulf sediments. The onset of modern-day monsoon conditions in the American Southwest required the presence of warm SSTs in the northern Gulf, which probably did not occur until after about 5.4 ka, when tropical diatoms and silicoflagellates became relatively common in the central Gulf. Modern east–west contrasts, which arise from late winter–early spring coastal upwelling on the mainland side and lower diatom productivity on the western side of the Gulf, commenced between 6.2 and 5.4 ka, possibly due to a shift in the direction of late winter–early spring winds more towards the southeast, or down the axis of the Gulf. This proposed wind shift might have ultimately been due to a late Holocene strengthening of ENSOlike conditions in the eastern equatorial Pacific. GEOGRAPHIC REGION: Guaymas Basin, Gulf of California, Mexico. PERIOD OF RECORD: 15 - 1 KYrBP DESCRIPTION: Guaymas Basin High-resolution Diatom and Silicoflagellate Data. Samples are from piston core JC56 and nearby gravity core GGC-55 (27°28.22'N, 112°6.33'W; 820 m water depth) The chronology for GGC55 and JPC56 is after Keigwin (2002), who recalibrated the results of Pride et al. (1999) using the revised reservoir correction of 725 years (BR =395 years) for the central Gulf. DATA: 1. Table 2. Percent values of key diatom taxa in samples studied from GGC55/JPC56 (see Section 2). Column 1: Depth (cm.) Column 2: Depth Composite (cmcd) Column 3: Age KYrBP Column 4: Actinocyclus curvatulus Column 5: Actinocyclus octonarius Column 6: Actinoptychus spp. Column 7: Azpeitia nodulifer Column 8: Coscinodiscus radiatus Column 9: Coscinodiscus spp. (large) Column 10: Cyclotella spp. Column 11: Roperia tesselata Column 12: Stephanopyxis spp. Column 13: Total number counted Depth Depth Comp. Age A.cur A.oct A.spp A.nod C.rad Co.spp Cy.spp R.tes S.spp Total Core GGC55: 9 9 2.20 3 3 29 14 19 2 29 1 1 318 20 20 2.33 5 4 23 12 14 3 38 1 314 30 30 2.44 5 5 23 10 20 3 34 1 311 40 40 2.55 9 4 23 2 11 6 37 10 311 50 50 2.67 10 2 28 4 14 4 36 2 309 59 59 2.77 12 5 30 5 15 5 26 2 310 70 70 2.90 7 3 24 8 14 6 36 3 319 80 80 3.01 6 4 28 7 11 3 40 1 308 90 90 3.12 9 3 37 5 13 4 25 3 316 100 100 3.24 12 3 37 4 14 5 24 2 312 110 110 3.35 9 3 28 8 10 4 33 5 310 120 120 3.46 11 8 21 7 9 5 31 7 1 317 130 130 3.58 12 10 25 8 12 2 28 4 313 140 140 3.69 3 3 27 9 16 7 32 3 306 150 150 3.80 4 3 20 10 16 2 45 1 306 160 160 3.92 5 9 28 4 17 3 32 2 308 170 170 4.03 6 4 40 3 10 5 30 3 309 180 180 4.15 7 4 39 3 9 2 32 4 308 190 190 4.26 4 4 31 10 13 4 33 2 312 200 200 4.37 1 1 9 50 8 1 27 1 307 209 209 4.48 4 4 22 19 17 2 30 2 305 220 220 4.60 1 9 14 29 13 1 32 1 317 230 230 4.71 6 4 49 4 11 6 19 1 307 240 240 4.83 6 6 30 24 4 5 19 6 322 Core JPC 56: 9 229 4.70 6 6 23 12 12 3 20 18 316 20 240 4.83 8 5 22 14 14 5 25 8 306 30 250 4.94 5 3 22 16 19 2 29 3 1 310 39 259 5.04 4 3 18 20 17 2 34 2 306 49 269 5.16 6 5 33 7 11 4 30 5 303 59 279 5.27 7 2 37 4 12 4 34 1 304 69 289 5.38 7 5 27 4 14 2 41 2 306 79 299 5.50 7 4 25 19 10 4 19 13 314 89 309 5.61 11 4 35 2 15 7 22 5 312 109 329 5.84 5 4 27 3 15 6 18 21 307 119 339 5.95 14 4 24 3 10 6 10 30 315 129 349 6.07 6 4 23 8 21 4 19 16 302 139 359 6.18 8 5 20 1 11 4 12 38 1 312 147 367 6.27 6 31 16 11 5 11 19 317 159 379 6.41 6 13 15 16 7 11 31 1 308 169 389 6.52 12 2 48 14 2 10 8 2 323 179 399 6.63 10 1 46 22 4 7 10 309 189 409 6.75 7 7 41 20 3 20 3 310 197 417 6.84 2 2 12 5 12 67 314 209 429 6.98 6 4 46 1 16 10 14 3 310 219 439 7.09 9 3 38 10 5 30 5 310 229 449 7.20 12 4 38 18 6 16 3 2 317 239 459 7.32 6 9 28 12 5 11 29 307 259 479 7.54 9 5 33 20 9 19 5 313 269 489 7.66 4 3 13 8 1 8 62 313 279 499 7.77 5 10 32 24 8 14 6 305 289 509 7.88 4 3 35 21 5 21 10 304 298 518 7.99 6 6 30 6 5 8 39 305 309 529 8.11 8 9 36 17 4 23 2 1 310 319 539 8.23 5 4 24 16 5 7 39 1 311 329 549 8.34 7 7 47 21 5 7 4 1 319 339 559 8.45 9 3 40 27 5 11 4 320 349 569 8.57 5 5 25 14 4 14 33 306 359 579 8.68 6 4 34 23 2 19 12 311 369 589 8.79 8 8 31 19 1 30 3 310 379 599 8.91 11 5 25 15 5 13 25 1 311 389 609 9.02 4 5 46 17 2 22 3 1 313 399 619 9.13 4 4 30 18 7 29 9 311 409 629 9.25 5 7 40 15 4 23 4 307 421 641 9.38 3 9 34 16 2 18 15 2 312 429 649 9.48 4 4 51 14 2 17 8 309 439 659 9.59 9 1 33 23 10 16 7 318 449 669 9.70 10 2 29 19 13 18 9 309 459 679 9.82 14 8 24 31 3 11 9 305 469 689 9.90 16 5 39 1 13 6 8 13 316 479 699 9.94 7 6 39 14 5 10 19 309 489 709 9.98 9 3 21 13 5 20 27 3 317 499 719 10.02 6 34 14 4 6 36 1 307 509 729 10.06 8 3 50 6 11 5 18 318 519 739 10.10 11 11 35 10 3 18 12 1 318 529 749 10.14 6 3 52 2 16 10 7 4 1 307 539 759 10.18 7 5 56 1 13 5 10 3 1 309 550 770 10.23 7 1 71 5 5 5 5 1 311 560 780 10.27 2 2 33 2 3 2 4 53 316 570 790 10.31 16 64 3 5 3 9 1 315 589 809 10.39 10 1 44 1 18 10 4 13 310 609 829 10.47 9 6 61 14 2 3 5 315 629 849 10.55 11 2 59 10 6 4 6 1 309 649 869 10.63 14 2 42 2 16 5 5 15 305 669 889 10.71 5 28 5 3 1 57 1 310 689 909 10.79 8 3 53 1 16 2 4 14 309 712 932 10.89 6 4 47 28 6 5 3 1 309 729 949 10.96 3 4 22 13 4 4 50 321 739 959 11.00 15 1 24 6 2 4 47 316 749 969 11.04 6 7 31 13 24 10 7 2 326 760 980 11.08 12 2 57 13 4 6 2 5 1 318 770 990 11.12 6 53 10 19 4 3 4 1 309 790 1010 11.21 28 41 11 10 1 4 5 309 799 1019 11.24 8 51 17 10 9 4 2 315 809 1029 11.28 8 2 51 13 8 6 8 2 2 316 829 1049 11.37 4 1 20 4 5 1 3 62 317 839 1059 11.41 8 2 44 6 27 5 5 3 323 849 1069 11.45 3 8 13 18 6 2 3 48 314 859 1079 11.49 11 1 43 11 17 3 8 3 3 315 870 1090 11.53 6 1 54 4 12 4 7 6 5 334 880 1100 11.57 4 4 25 45 11 2 7 2 318 890 1110 11.61 8 5 36 16 14 5 12 2 318 902 1122 11.67 12 1 22 9 13 4 1 38 310 909 1129 11.73 2 1 21 31 19 4 19 2 1 309 920 1140 11.83 1 4 10 67 10 3 6 312 930 1150 11.92 1 7 77 4 3 8 315 940 1160 12.01 2 3 18 46 11 5 13 1 315 949 1169 12.09 2 3 19 35 26 4 11 309 960 1180 12.19 1 3 11 67 9 1 8 1 316 970 1190 12.28 4 4 18 36 20 5 11 1 316 979 1199 12.36 3 2 21 34 14 4 21 310 990 1210 12.46 4 3 18 32 26 5 13 1 308 998 1218 12.53 7 5 22 33 13 4 12 3 314 1009 1229 12.63 3 4 17 47 16 1 12 1 315 1030 1250 12.82 6 6 21 47 11 3 5 317 1051 1271 13.01 9 10 30 23 13 3 10 317 1071 1291 13.19 11 4 45 10 17 4 6 2 319 1090 1310 13.36 5 2 30 19 9 1 33 330 1111 1331 13.50 9 4 48 13 12 5 7 1 1 324 1130 1350 13.58 4 3 22 41 6 3 7 14 1 312 1149 1369 13.65 8 4 32 31 11 4 9 1 308 1169 1389 13.73 5 1 74 6 8 3 2 313 1190 1410 13.82 4 3 37 29 8 2 18 314 1210 1430 13.89 6 4 26 43 10 1 10 309 1230 1450 13.97 4 3 60 10 9 13 2 317 1249 1469 14.05 8 6 40 25 8 3 10 314 1270 1490 14.13 9 6 47 13 9 4 13 320 1290 1510 14.21 6 2 33 38 8 6 5 1 318 1310 1530 14.29 7 2 32 29 12 7 10 1 310 1340 1560 14.41 6 2 44 30 10 3 5 318 1361 1581 14.49 2 6 25 40 10 7 10 321 1380 1600 14.57 10 4 26 40 7 5 7 1 320 1399 1619 14.64 5 3 24 45 5 4 14 1 319 1420 1640 14.72 10 5 29 33 11 4 6 316 1440 1660 14.80 3 3 32 34 11 10 8 1 316 1449 1669 14.84 7 2 36 25 14 3 12 1 308 2. Table 3. Percent values of silicoflagellate taxa in samples studied from GGC55/JPC56 (see Section 2) Column 1: Depth (cm.) Column 2: Depth Composite (cmcd) Column 3: Age KYrBP Column 4: Dictyocha aculeata Column 5: D. aff. aculeata Column 6: D. aff. aspera Column 7: D. aspinosa Column 8: D. calida Column 9: D. calida ampliata Column 10: D. perlaevis Column 11: D. perlaevis (long) Column 12: D. aff. prelaevis Column 13: D. stapedia Column 14: D. subaculeata Column 15: D. sp. new Column 16: Distephanus speculum Column 17: D. quinquangellus Column 18: Octactis pulchra (sm) Column 19: O. pulchra (med) Column 20: O. pulchra (lrg) Column 21: Count Depth DepthC Age D.acu D.aff D.aff D.asp D.cal D.ca D.per D.pl D.aff D.sta D.sub D.new D.spe D.qui O.pul O.pul O.pul Count GGC 55 9 9 2.20 13 6 6 11 8 25 1 10 15 8 200 20 20 2.33 14 3 6 12 3 25 1 2 16 15 5 100 30 30 2.44 12 6 8 23 4 17 6 16 8 100 40 40 2.55 3 3 9 2 26 33 11 13 100 50 50 2.67 6 11 1 10 1 27 1 19 17 7 100 59 59 2.77 11 15 1 31 11 25 6 100 70 70 2.90 3 3 4 1 14 2 22 28 15 10 200 80 80 3.01 3 2 4 12 5 37 1 1 16 16 3 100 90 90 3.12 2 1 11 1 10 1 34 1 15 21 5 200 100 100 3.24 8 1 3 15 2 43 11 14 5 200 110 110 3.35 2 10 3 11 43 1 9 12 9 100 120 120 3.46 1 1 5 1 15 1 36 19 18 5 200 130 130 3.58 4 8 2 1 6 49 13 15 4 200 140 140 3.69 1 9 4 20 6 39 10 11 70 150 150 3.80 5 19 1 20 4 31 1 7 11 1 100 160 160 3.92 1 11 1 9 3 61 4 7 3 100 170 170 4.03 2 11 6 11 43 1 1 8 11 6 100 180 180 4.15 1 28 7 3 36 5 12 8 100 190 190 4.26 5 22 3 8 5 34 9 10 4 100 200 200 4.37 1 3 9 10 4 15 3 47 1 1 3 6 2 200 209 209 4.48 5 8 2 15 10 30 8 10 12 60 220 220 4.60 6 11 5 1 52 1 9 12 3 100 230 230 4.71 6 3 15 7 53 9 5 3 100 240 240 4.83 2 2 6 6 1 14 1 50 1 8 13 2 200 JPC 56 9 229 4.70 7 6 2 2 7 2 43 2 14 15 4 200 20 240 4.83 10 2 3 14 3 34 1 8 17 8 100 30 250 4.94 12 5 3 14 8 10 1 24 17 6 100 39 259 5.04 5 4 3 3 24 9 23 7 16 6 100 49 269 5.16 6 5 6 1 12 4 29 15 15 7 100 59 279 5.27 4 2 19 4 15 3 31 3 12 8 100 69 289 5.38 3 6 2 15 50 7 10 7 100 79 299 5.50 1 9 11 14 6 33 1 1 11 8 5 100 89 309 5.61 4 1 13 2 42 23 12 5 100 109 329 5.84 1 1 7 2 30 16 39 4 100 119 339 5.95 1 1 10 3 6 2 43 17 15 2 100 129 349 6.07 1 11 8 1 4 1 31 2 12 28 4 200 139 359 6.18 18 4 8 49 11 8 2 100 147 367 6.27 4 3 3 45 29 16 2 200 159 379 6.41 4 16 5 3 1 21 32 14 4 100 169 389 6.52 1 19 3 1 3 30 26 13 4 100 179 399 6.63 2 11 1 3 1 26 40 13 4 110 189 409 6.75 18 1 2 2 28 27 21 4 200 197 417 6.84 14 1 1 33 33 13 6 200 209 429 6.98 7 2 2 1 28 30 25 5 100 219 439 7.09 1 4 4 3 1 33 33 12 9 100 229 449 7.20 9 2 2 35 1 22 19 10 100 239 459 7.32 1 8 1 1 1 38 1 24 24 3 300 259 479 7.54 6 3 1 52 17 15 8 200 269 489 7.66 11 7 3 1 36 17 24 4 200 279 499 7.77 5 3 19 42 28 3 100 289 509 7.88 3 2 3 42 1 25 18 6 100 298 518 7.99 2 1 39 41 9 8 100 309 529 8.11 2 1 2 43 20 23 10 100 319 539 8.23 6 3 47 17 19 8 100 329 549 8.34 5 2 2 2 27 39 14 10 200 339 559 8.45 1 1 5 1 43 11 29 9 100 349 569 8.57 4 1 68 15 11 3 200 359 579 8.68 4 6 2 1 62 7 9 9 150 369 589 8.79 1 2 41 17 32 7 150 379 599 8.91 2 2 2 48 19 24 5 200 389 609 9.02 1 2 1 63 17 13 3 100 399 619 9.13 1 2 1 61 14 17 5 200 409 629 9.25 4 45 18 29 4 100 421 641 9.38 2 1 3 1 53 21 16 5 200 429 649 9.48 1 1 62 17 16 2 300 439 659 9.59 2 1 7 34 30 23 5 200 449 669 9.70 1 4 1 63 18 11 2 100 459 679 9.82 1 82 5 7 5 300 469 689 9.90 2 1 5 51 21 19 3 200 479 699 9.94 2 1 2 61 1 18 9 6 100 489 709 9.98 58 16 19 7 100 499 719 10.02 2 2 52 23 15 6 100 509 729 10.06 2 4 5 4 3 60 8 9 5 100 519 739 10.10 3 1 1 5 59 14 13 4 100 529 749 10.14 2 1 2 51 32 9 3 100 539 759 10.18 1 6 1 49 22 17 4 100 550 770 10.23 1 2 9 1 49 10 20 8 100 560 780 10.27 2 3 48 22 15 10 100 570 790 10.31 7 6 2 1 66 5 6 7 100 589 809 10.39 6 51 1 27 10 5 100 609 829 10.47 1 3 24 37 25 10 100 629 849 10.55 2 5 10 27 40 16 100 649 869 10.63 3 5 2 61 15 11 3 100 669 889 10.71 16 16 31 31 6 100 689 909 10.79 1 1 13 49 16 11 9 100 712 932 10.89 1 11 2 28 25 29 4 100 729 949 10.96 2 2 45 23 20 7 100 749 969 11.04 7 38 25 25 5 100 760 980 11.08 4 14 53 28 1 100 770 990 11.12 1 3 2 43 31 18 2 100 790 1010 11.21 1 1 49 21 26 4 200 809 1029 11.24 1 3 1 44 24 22 8 200 829 1049 11.37 7 9 20 37 23 4 100 849 1069 11.45 32 8 7 35 18 2 200 870 1090 11.53 1 20 1 7 11 42 17 2 200 880 1100 11.57 68 9 1 1 16 4 2 200 890 1110 11.61 91 4 2 3 1 200 902 1122 11.67 83 1 2 1 12 2 200 909 1129 11.73 97 3 1 200 920 1140 11.83 4 33 13 13 23 10 4 100 930 1150 11.92 56 4 16 2 6 12 50 940 1160 12.01 42 8 16 2 2 18 12 50 949 1169 12.09 2 50 6 18 14 6 4 50 960 1180 12.19 2 24 8 26 2 24 12 2 50 970 1190 12.28 4 28 8 14 2 26 18 50 979 1199 12.36 40 1 14 11 1 19 12 2 100 990 1210 12.46 3 26 14 8 23 20 6 100 998 1218 12.53 1 26 3 27 22 19 2 100 1009 1229 12.63 1 2 35 41 6 8 5 3 200 1030 1250 12.82 2 14 2 25 42 16 2 200 1050 1270 13.01 6 20 58 16 2 200 1071 1291 13.19 1 11 1 17 53 19 200 1090 1310 13.36 1 5 10 64 18 2 100 1111 1331 13.50 4 1 2 1 71 18 4 200 1130 1350 13.58 9 2 8 48 34 1 200 1149 1369 13.65 1 14 1 2 55 25 4 200 1169 1389 13.73 2 11 2 2 61 20 2 100 1190 1410 13.82 15 4 4 53 24 2 200 1210 1430 13.89 2 8 6 1 54 27 4 200 1230 1450 13.97 2 2 2 1 8 4 66 15 2 200 1249 1469 14.05 5 4 2 80 9 100 1270 1490 14.13 5 6 75 13 1 100 1290 1510 14.21 7 2 2 1 55 31 2 100 1310 1530 14.29 13 1 44 41 100 1340 1560 14.41 11 2 7 51 28 1 100 1361 1581 14.49 11 1 9 4 38 31 6 100 1380 1600 14.57 5 1 11 9 54 21 100 1399 1619 14.64 19 5 3 7 35 28 3 100 1420 1640 14.72 15 4 18 26 39 1 100 1440 1660 14.80 1 17 3 30 24 24 1 100 1449 1669 14.84 1 1 8 5 39 26 18 4 200