Extremely High Primary Productivity and Organic Matter Enrichment in Lacustrine Sediments: Late Triassic Chang 7<sup>3</sup> Sub-Member, Western Ordos Basin

<div>Discrimination diagram of <svg height="11.5564pt" id="M58" style="vertical-align:-2.26807pt" version="1.1" viewbox="-0.0498162 -9.28833 70.1887 11.5564" width="70.1887pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z"></path></g><g transform="matrix(.013,0,0,-0.013,4.498,0)"><path d="M493 503C489 551 484 614 483 650H43V622C120 616 128 611 128 525V126C128 40 120 34 40 28V0H312V28C221 34 213 40 213 126V307H316C407 307 412 296 424 227H453V420H424C412 355 407 346 316 346H213V584C213 613 216 616 246 616H322C398 616 419 607 436 579C449 559 455 539 464 499L493 503Z"></path></g><g transform="matrix(.013,0,0,-0.013,11.127,0)"><path d="M380 106C343 72 306 56 265 56C195 56 116 112 115 248C235 252 361 262 377 265C396 269 400 277 400 297C400 374 333 449 250 449H249C198 449 144 421 103 376S37 269 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276 437 248 419C223 402 201 387 181 372V451C137 432 90 420 42 411V388C96 378 102 374 102 310V104C102 38 97 33 29 26V0H246V26C187 32 181 36 181 104V339C211 365 250 390 290 390C357 390 381 345 381 276V109C381 40 374 32 315 26V0H524Z"></path></g><g transform="matrix(.013,0,0,-0.013,92.331,0)"><path d="M275 270C275 450 212 609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z"></path></g></svg> for the influence of hydrothermal activity [<a href="/journals/geofluids/2022/2150607/#B60">60</a>] in the Chang 7<sup>3</sup> black shale.</div>

Geofluids

fig11

Figure 11

Figure 11: Extremely High Primary Productivity and Organic Matter Enrichment in Lacustrine Sediments: Late Triassic Chang 7<sup>3</sup> Sub-Member, Western Ordos Basin 

Figure 11 | Extremely High Primary Productivity and Organic Matter Enrichment in Lacustrine Sediments: Late Triassic Chang 73 Sub-Member, Western Ordos Basin 