魏東+馬中豪+陳清石

摘要：鄂爾多斯盆地渭北隆起蘊(yùn)藏著豐富的煤、油頁(yè)巖、石油、鈾等能源礦產(chǎn)，多種能源礦產(chǎn)共存與構(gòu)造特征關(guān)系、多種能源礦產(chǎn)協(xié)同勘探已成為地學(xué)界研究的熱點(diǎn)課題。在分析總結(jié)多種能源礦產(chǎn)時(shí)空分布規(guī)律及成因聯(lián)系的基礎(chǔ)上，以構(gòu)造演化特征為主線(xiàn)，重點(diǎn)探討了構(gòu)造運(yùn)動(dòng)期次、沉積建造、構(gòu)造單元特征、褶皺構(gòu)造與多種能源礦產(chǎn)的關(guān)系。結(jié)果表明：渭北隆起印支期—燕山早期的成盆-差異升降運(yùn)動(dòng)形成了本區(qū)穩(wěn)定的深湖—半深湖相含油頁(yè)巖與不穩(wěn)定的沼澤相含煤沉積建造組合；燕山中晚期的構(gòu)造熱事件促使油頁(yè)巖成熟生烴、煤級(jí)升高；燕山期—喜山期的斷裂、褶皺構(gòu)造為油氣和富鈾低溫油水熱液運(yùn)移和成藏提供了通道和富集成礦（藏）的場(chǎng)所；喜山期的抬升冷卻和南緣斷陷作用使得多種能源礦產(chǎn)共存富集得到了最終保存定位，且統(tǒng)一成礦年齡集中在74～122 Ma，稍晚于燕山中晚期的構(gòu)造熱事件。綜合考慮地質(zhì)、經(jīng)濟(jì)和技術(shù)因素，將彬旬凹陷成礦區(qū)劃分為4個(gè)協(xié)同勘探區(qū)，并建立了合理的勘探模式。

關(guān)鍵詞：能源礦產(chǎn)；共存富集；構(gòu)造演化；沉積建造；構(gòu)造熱事件；協(xié)同勘探；渭北隆起；鄂爾多斯盆地

中圖分類(lèi)號(hào)：P618；TE122 文獻(xiàn)標(biāo)志碼：A

Abstract： Weibei uplift in Ordos Basin is rich in coal， oil shale， oil， uranium and other energy minerals， the relationship between the coexistence of multiple energy minerals and the structural characteristics， and the co-exploration of multiple energy minerals are hot topics. On the basis of analyzing and summarizing the spatial distribution and genetic relationship of multiple energy minerals， the relationship between period of tectonic movement， sedimentary formation， characteristics of tectonic unit， fold structure and multiple energy minerals were discussed according to the characteristics of tectonic evolution. The results show that the basin formation-differential uplift in Indosinian-Early Yanshanian forms the stable deep and semi-deep lacustrine facies containing oil shale and the unstable swamp facies containing coal sedimentary formation in Weibei uplift； the tectonic thermal events in Middle-Late Yanshanian cause the oil shale hydrocarbon generation and coal quality improved； the fault and fold structure in Yanshanian-Himalayan Period provide the channel and interspace for the migration and accumulation of petroleum and hydrothermal solution containing oil water with low temperature and rich uranium； rising-cooling and the southern rift in Himalayan Period keep the coexistence and accumulation of multiple energy minerals， and the unified metallogenic ages are 74-122 Ma， which are later than the tectonic thermal events in Middle-Late Yanshanian. Finally， based on the geological， economic and technical factors， the metallogenic provinces of Binxun depression were divided into 4 co-exploration areas， and the corresponding reasonable exploration models were built.

Key words： energy mineral； coexistence and accumulation； tectonic evolution； sedimentary formation； tectonic thermal event； co-exploration； Weibei uplift； Ordos Basin

0 引 言

渭北隆起大地構(gòu)造位置處于鄂爾多斯盆地西南部NE—SW向構(gòu)造帶上，自北向南由彬旬凹陷、北緣撓褶帶、銅川斷褶帶組成，區(qū)內(nèi)石油、油頁(yè)巖、煤、砂巖型鈾礦等能源礦產(chǎn)共存富集。長(zhǎng)期以來(lái)，盆地構(gòu)造演化與多種能源礦產(chǎn)共存關(guān)系的研究一直是地學(xué)界十分引人關(guān)注的課題，正在逐漸成為國(guó)家重大基礎(chǔ)專(zhuān)項(xiàng)研究和亟待解決的科學(xué)問(wèn)題[1-3]。近年來(lái)，渭北隆起雖然在油氣、煤、鈾、油頁(yè)巖等單一礦種的成礦規(guī)律、成礦條件和富集機(jī)理等方面的研究取得了較大進(jìn)展，但遺憾的是多年來(lái)各類(lèi)礦產(chǎn)由多部門(mén)獨(dú)立勘探開(kāi)發(fā)和研究，對(duì)于多種能源礦產(chǎn)的整合研究和協(xié)同勘探開(kāi)發(fā)則較為薄弱，對(duì)于多種能源礦產(chǎn)共存與構(gòu)造演化的關(guān)系研究需要更加深入。渭北隆起彬縣—銅川地區(qū)勘探歷史久遠(yuǎn)，資料豐富，特別是近十年來(lái)本區(qū)油頁(yè)巖、砂巖型鈾礦的整裝勘查和綜合研究成果顯著，新發(fā)現(xiàn)了較多的油頁(yè)巖、鈾、煤、石油礦產(chǎn)地，這一地區(qū)正在成為探索研究渭北隆起多種能源礦產(chǎn)共存與構(gòu)造演化及其耦合成礦效應(yīng)的理想基地。本文分析總結(jié)了多種能源礦產(chǎn)時(shí)空分布規(guī)律及成因聯(lián)系，以構(gòu)造演化特征為主線(xiàn)，重點(diǎn)探討了構(gòu)造演化與沉積建造、構(gòu)造熱事件與多種能源礦產(chǎn)、褶皺構(gòu)造與油鈾成礦（藏）的關(guān)系，進(jìn)而劃分了4個(gè)協(xié)同勘探區(qū)，并建立了合理的勘探模式。