SCIENCE GOALS AND OBJECTIVES: THE NEOPROTEROZOIC ERA (541-1000 MA) WAS A TRANSITIONAL TIME IN THE HISTORY OF LIFE THAT INCLUDED BOTH THE EMERGENCE OF EARLY ANIMALS AND OTHER COMPLEX EUKARYOTES IN THE MIDST OF CRYOGENIAN CLIMATE PERTURBATIONS (635-850 MA). HOWEVER THE SPECIFICS OF BOTH THE CLIMATE RECORD AND THE EVOLUTIONARY TEMPO OF EUKARYOTIC DIVERSIFICATION REMAIN POORLY RESOLVED. FIRST MULTIPLE ASPECTS OF THE CLIMATE RECORD COULD BE BETTER KNOWN. PERHAPS MOST IMPORTANTLY TEMPERATURE CONSTRAINTS ACROSS THE BACKGROUND CLIMATE AND BEFORE DURING AND AFTER THE 'SNOWBALL EARTH' GLACIAL PERTURBATIONS WILL ADDRESS DECADES LONG UNCERTAINTIES ABOUT THE PRECAMBRIAN CLIMATE. SECOND WHILE GREAT STRIDES HAVE OCCURRED WITH THE FOSSIL AND BIOMARKER RECORD OF LIFE HIGH RESOLUTION RECORDS TO DEFINE THE TEMPO OF EVOLUTION ARE RARE. WE PROPOSE A HOLISTIC STUDY OF THE THERMAL MATURITY OF SHALLOWLY BURIED NEOPROTEROZOIC STRATA GLOBALLY TO ASSESS THE BEST SITES ABLE TO PROVIDE A PAIRED HIGH RESOLUTION CLUMPED ISOTOPE AND BIOMARKER RECORD THROUGH THE NEOPROTEROZOIC. HYPOTHESES AND MEASUREMENTS: WE WILL PAIR CARBONATE CLUMPED ISOTOPIC ANALYSIS WITH BIOMARKER ANALYSES AND BURIAL HISTORY MODELING TO ASSESS THE THERMAL MATURITY OF KEY NEOPROTEROZOIC STRATA. WE WILL: A) ASSESS THE OVERPRINT OF DIAGENESIS USING PAIRED CALCITE AND DOLOMITE SAMPLES FROM NEOPROTEROZOIC CARBONATES THROUGH PETROGRAPHY PHASE-SPECIFIC CARBONATE CLUMPED ISOTOPE THERMOMETRY ANALYSIS AND SECONDARY ION MASS SPECTROMETRY (SIMS) ANALYSIS OF ?13C AND ?18O VARIABILITY ACROSS 10S OF MICRONS B) USE BIOMARKERS AND SYNCHROTRON BASED MICROANALYSIS TO ASSESS THE PRESERVATION OF BIOMARKERS AND DIVERSITY OF EUKARYOTES IN A RANGE OF DEPOSITIONAL ENVIRONMENTS. IN THIS PROPOSED WORK WE WILL LEVERAGE INSIGHTS GAINED FROM OUR WORK ON THE REGIONAL VARIABILITY OF THERMAL MATURITY IN OMAN AND NE SVALBARD AND TEST THE POTENTIAL OF A RANGE OF OTHER SHALLOWLY BURIED SITES. PAIRING BIOMARKER RESULTS WITH CARBONATE CLUMPED ISOTOPE (?47) THERMOMETRY HAS NOT BEEN DONE TO DATE BUT OFFERS A PATH FORWARD TO BETTER UNDERSTAND BOTH THE ORGANIC AND INORGANIC RECORDS PRESERVED IN ANCIENT ROCK SUCCESSIONS. OUR PRELIMINARY RESULTS FROM NE SVALBARD AND OMAN INDICATE THAT REGIONAL DIFFERENCES IN THERMAL HISTORY LEAD TO VARYING DEGREES OF RECRYSTALLIZATION SOLID STATE REORDERING AND BIOMARKER DESTRUCTION. WE WILL EXPAND ON OUR EXISTING BURIAL HISTORY MODEL TO UTILIZE THE DEGREE OF MISMATCH BETWEEN CALCITE AND DOLOMITE CLUMPED ISOTOPE TEMPERATURES AND THE BIOMARKER PRESERVATION TO PINPOINT THERMAL MATURITY. WITH OUR THREE-PART APPROACH USING CLUMPED ISOTOPE THERMOMETRY BIOMARKER ANALYSIS AND MODELING WE AIM TO ASSESS THE POTENTIAL OF DIFFERENT REGIONS TO DETERMINE HOW TEMPERATURE CO-VARIED WITH THE EVOLUTION OF COMPLEX LIFE. SIGNIFICANCE AND RELEVANCE: WE EXPECT THAT OUR INVESTIGATION OF THE THERMAL MATURITY OF SHALLOWLY BURIED NEOPROTEROZOIC STRATA AND THE INSIGHTS WE WILL GAIN ON CLIMATE PERTURBATIONS AND ASSOCIATED EUKARYOTIC EXPANSION WILL SIGNIFICANTLY CONTRIBUTE TO THE BROADER ASTROBIOLOGY COMMUNITY. THIS PROPOSED WORK FALLS WITHIN THE SCOPE OF THE EXOBIOLOGY PROGRAM ELEMENT SUBSECTION ON "EVOLUTION OF ADVANCED LIFE" DUE TO ITS FOCUS ON HABITATS FOR EARLY ANIMAL LIFE ASSOCIATED WITH NEOPROTEROZOIC CLIMATE PERTURBATIONS. IN ADDITION THE SOLICITATION SPECIFICALLY HIGHLIGHTS 'SNOWBALL EARTH' EVENTS. CONCERTED INVESTIGATION OF THIS TIME PERIOD PROMISES TO TRANSFORM OUR UNDERSTANDING OF THE FACTORS DRIVING THE EXPANSION OF COMPLEX LIFE ON EARTH.